JP4568481B2 - Pollutant gas cleaning system and pollutant gas cleaning method using the cleaning system - Google Patents

Description

【００９３】
この試験の結果、本発明例（Ｎｏ． Ａ、Ｎｏ． Ｃ、Ｎｏ． ＤＡ）は、１５％程度の圧力損失の増加であったが、比較例（Ｎｏ． Ｅ）は自重で押し潰され変形し、圧力損失が２倍以上に増加した。
つぎに、得られた各気体洗浄用充填材５ｇ を、固有の悪臭を有するトリメチルアミンの０．０１％水溶液１００ｍｌ 中に投入し、水溶液の臭いを人間の臭覚で試験した。その結果、本発明例の気体洗浄用充填材（Ｎｏ．
ＤＡ）を投入した場合にのみ、トリメチルアミンの悪臭が消臭された。
（実施例２）
処理量３０ｋｇ／日の処理能力を有する食品廃棄物分解装置から排出される気流（空気）を、図１に概要を示す洗浄装置を用いて洗浄した。
【００９４】
この食品廃棄物分解装置は、横長で筒状の分解室を有し、上面に気密性で開閉可能なごみ投入口を有している。分解室内には、細菌を担持し長時間使用するおが屑が入れられている。ごみ投入口から食品廃棄物を投入したのち、送風機で新鮮な空気を分解室に送入しながら、水平なシャフトに垂直に取り付けた回転翼により内容物（食品廃棄物）を切り返す。さらに、分解室の湿度・温度を制御装置で一定範囲内に調整しながら、回転翼の回転と停止を１５分ごとに繰り返す。この食品廃棄物分解装置の排気孔からは、強い悪臭を有し、炭酸ガス、有害ガス、微生物、胞子等を含んだ高湿度の５０℃程度の気流が排出される。
【００９５】
使用した洗浄装置１は、縦長の直方体（８００ ×８００ ×高さ１５００ｍｍ）で、上部側面に処理気体を導入するための吸気口１ａを有し、下部側面に洗浄済の気体を排出する排気口９を有する。洗浄薬液槽６と分離して、洗浄薬液槽６の液面の上部に気体洗浄用充填材を含む層２が設けられている。また、吸気口より下部で、気体洗浄用充填材を含む層２より上部に噴霧手段３が設けられている。噴霧手段３（スプレーガン）は、洗浄すべき汚染気体と並流して、噴射口から１５ｃｍの位置でレーザ光散乱式粒度分布測定法で測定し平均粒径が２０μｍの洗浄薬液のミストを噴霧可能としている。気体洗浄用充填材を含む層２は、気体洗浄用充填材を厚さ：３０ｃｍ積層して、形成した。なお、使用した気体洗浄用充填材は、実施例１で用いた、充填材素材（紙粒）にＡ処理を施したＮｏ．
Ａとした。
【００９６】
また、気体洗浄用充填材を含む層２には、洗浄薬液貯留槽７から液流ポンプ４ａで吸引した洗浄薬液を供給手段４（ここでは回転式散水機を利用）で散布・供給され、気体洗浄用充填材を含む層２は洗浄薬液で湿潤した状態とされている。
噴霧する洗浄薬液および気体洗浄用充填材を含む層に含浸・供給される洗浄薬液は、直鎖分子で分子量が極限粘度法で１．８ ×１０^７
である、アクリル酸１５モル％とジメチルアミノメチル基１５モル％が結合した両性ポリアクリルアミドを５ｐｐｍ 、「両親媒性溶剤」であるトリエチレングリコールジメチルエーテルを２ｐｐｍ
、緩衝剤として重炭酸ナトリウムを０．１ｐｐｍ、殺菌・静菌剤として２−Ｎ−オクチル−４−イソチアゾリン−３−オン、およびヘキサメチレン ビグアニドのナトリウム塩をそれぞれ５ｐｐｍ
を含む水溶液（洗浄薬液ａ）とした。なお、比較として、洗浄薬液ａから、「両親媒性溶剤」であるトリエチレングリコールジメチルエーテルを除いた洗浄薬液（洗浄薬液ｂ）についても、実験した。
【００９７】
上記した食品廃棄物分解装置のごみ投入口から、１ 回に、生野菜の刻みくず１５ｋｇ、賞味期限切れの米飯５ｋｇ、および生マグロのアラ１０ｋｇづつを、隔日に計３回（６日間）投入した。そして、食品廃棄物分解装置の排気孔から排出される気流（空気）をサンプルとして採取して臭気濃度を測定した。サンプルの採取は、ごみ投入から５時間後と、２３時間後とし、ごみ投入ごと（計３回）に繰返し（計６回採取）行った。なお、切り返しを行うと臭気濃度や菌類の排出濃度が上昇するため、排出される気流の採取は、回転翼で分解室の内容物を切り返し中とした。ごみ投入から５時間後が臭気濃度が最高になり、２３時間後に最低濃度となることを確認しており、ごみ投入から５時間後に採取した場合が最高濃度を、２３時間後に採取した場合が最低濃度を表すことになる。最高濃度、最低濃度とも３回の値を平均し、平均値を臭気濃度として用いた。
【００９８】
採取したサンプルは、図１に示す洗浄装置の吸気口１ａにポンプで供給した。洗浄装置１内では、吸気された汚染気体と並流して、上記した洗浄薬液を噴霧手段３から、平均粒径が２０μｍのミストとなるように、噴霧するとともに、上記した洗浄薬液を供給・含浸した気体洗浄用充填材を含む層２を２ｍ^３
／分の割合で通過させて、汚染気体を洗浄し、排気口９から排出した。排出された気流をサンプルとして臭気濃度を測定した。
【００９９】
臭気濃度の測定は、の測定対象気体（サンプル）に新鮮な空気を希釈し続けて、正常な嗅覚をもつ６人が臭気を嗅ぎ分けられなくなった時点の希釈倍率を求めることにより行った。６人のうちの最高値と最低値を除いた、４人の測定値（希釈倍率）の平均値を臭気濃度とした。
食品廃棄物分解装置から排出された気流の臭気濃度と、洗浄装置で洗浄されたのち気体の臭気濃度から、本発明の洗浄システムによる汚染気体の清浄化率を求めた。清浄化率（％）は、｛（食品廃棄物分解装置から排出された気流の臭気濃度）−（洗浄装置で洗浄されたのちの気体の臭気濃度）｝／（食品廃棄物分解装置から排出された気流の臭気濃度）×１００
（％）で定義される値である。
【０１００】
得られた結果を表２に示す。
【０１０１】
【表２】

【０１０２】
本発明範囲の、気体洗浄用充填材、洗浄薬液を用いた、洗浄システム（本発明例）では、清浄化率がほぼ１００ ％と、汚染物質をほぼ完全に除去できるが、本発明範囲から外れた洗浄薬液を用いた場合には、清浄化率は低く、汚染物質を完全には除去できていない。この結果から、「両親媒性溶剤」の有用性が確認できた。
（実施例３）
解体直前の鉄筋コンクリート造りの建造物の一室（空間容量：１２０ ｍ^３ ）で空気中に含まれる硫化水素の解毒 （除去）実験を行った。なお、部屋は完全に気密性とするため、ドアの隙間、開口部分をパテで充填し、窓ガラスの隙間を粘着テープでシールした。
【０１０３】
このような部屋の中央で、まず、三角フラスコに入れた硫化鉄に希硫酸を加えて硫化水素（許容濃度：１０ｐｐｍ 、致死濃度：１０００ｐｐｍ ）を発生させ、扇風機で空気を攪拌しながら室内のガス濃度を均一化した。ついで、防毒マスクを着用した測定者により、北川式ガス検知管で室内の硫化水素ガス濃度を測定したところ、６０ｐｐｍ
であった。１時間後に同様に室内の硫化水素ガス濃度を測定したところ、壁、床などと反応したり、室外に漏れたりしたため、５４ｐｐｍ であった（ガス濃度の低下率：１０％／時）。このガス濃度：５４ｐｐｍ
を初期値とした。
【０１０４】
ついで、上記した洗浄薬液を、約９０ｇ ／分の噴霧量で３分間、室内くまなく噴霧した。噴霧は、可動式３流体式噴霧装置を用いて行い、その際の洗浄薬液の噴霧ミストの平均粒径は噴射口から１５ｃｍの位置でレーザ光散乱式粒度分布測定法で測定して１０μｍであった。使用した洗浄薬液は、実施例２で使用した洗浄薬液ａとした。
【０１０５】
噴霧後１〜２分後にマスクを外したところ、嗅覚的には大部分の硫化水素は除去できたと感じられたが、噴霧後２〜３分後に室内の硫化水素ガス濃度を測定したところ、１２ｐｐｍ
であった。｛（初期ガス濃度）−（噴霧後のガス濃度）｝／（初期ガス濃度）×１００ （％）で定義される清浄化率は７８％となる。
上記した洗浄薬液の噴霧により、室内に拡散した硫化水素のほぼ１００ ％が洗浄薬液の噴霧ミストに捕捉されたが、そのうち８０％相当分しか床に沈降しなかった。残り２０％相当分はミスト粒径が小さく、しかも水分の蒸発で粒径が縮小し硫化水素を保持したまま、床に沈降せず、空間に浮遊している状態で検知管に検出されたが、ゲル状態で鼻孔に入ったため、硫化水素臭が感じられなかったものと考えられる。
【０１０６】
ついで、上記したように、室内で洗浄薬液を噴霧された室内空気を、図１に示す洗浄装置１の吸気口１ａに吸引し、該室内空気の洗浄を行った。
使用した洗浄装置は、内部に、気体洗浄用充填材を含む層２を有し、さらに気体洗浄用充填材を含む層２と分離して、気体洗浄用充填材を含む層２の下部で、液面を気体洗浄用充填材を含む層２より低い位置にした洗浄薬液槽６を有し、さらにこの洗浄薬液槽６に配管を介して、洗浄薬液を貯留する洗浄薬液貯槽７を連設した。また、この洗浄装置には、洗浄薬液貯槽７から液流ポンプ４ａを介し洗浄薬液を供給される、回転式散水器からなる洗浄薬液の供給手段４が配設されている。この供給手段４により、気体洗浄用充填材を含む層２に洗浄薬液が供給され、含浸されて、気体洗浄用充填材を含む層２は湿潤性を保持している。また、この洗浄装置１では、汚染気体（室内空気）を湿潤な気体洗浄用充填材を含む層２に通して洗浄し、清浄化して排気口９から排出する。
【０１０７】
気体洗浄用充填材を含む層２は、紙粒に耐水性のみを付与するＢ処理を施された気体洗浄用充填材（Ｎｏ． Ｂ）（実施例１参照）を、ステンレス鋼金網上に水平に厚さ：３０ｃｍに積層した。また、使用した洗浄薬液は、薬液１ｋｇあたり、「両親媒性溶剤」としてトリエチレングリコールジメチルエーテルを２０ｇ
、さらに水酸化ナトリウムを８０ｇ 、重炭酸ナトリウムを４０ｇ 、酸化剤としての過硫酸ナトリウムを１０ｇ 、有機溶剤で硫化水素と親和性の大きいトリエタノールアミンを４０ｇ
、および水を８１０ｇ、混合し溶解した水溶液（洗浄薬液ｃ）とした。使用した洗浄装置は、既存のドラム缶（２００ Ｌ程度）を改造して作製した。構造が簡単なため、圧力損失は２０ｍｍ
ａｑ 程度で、６〜８ｍ^３ ／分程度の汚染気体の洗浄が可能である。
【０１０８】
硫化水素を室内に拡散され、洗浄薬液を噴霧後の室内空気を、上記したような条件の図１に示す洗浄装置で洗浄したのち、排気口９から排出された空気について、北川式ガス検知管を用いて同様に硫化水素ガスの濃度を測定したが、全く検出されなかった。
（実施例４）
実施例３と同じ気密性の部屋で、硫黄を燃焼させて亜硫酸ガス（許容濃度：２ｐｐｍ 、致死濃度：４００ｐｐｍ）を発生させ、室内のガス濃度を均一化したのち、実施例３と同様に防毒マスクを着用した測定者により、室内の二酸化硫黄濃度を測定したところ、４０ｐｐｍ
であった。
【０１０９】
ついで、実施例３と同様に、室内くまなく洗浄薬液を噴霧した。使用した洗浄薬液は、実施例３と同様（洗浄薬液ａ）とした。噴霧後の室内におけるガス濃度を、実施例３と同様に、北川式ガス検知管で測定したところ、４ｐｐｍ
を得た。清浄化率は９０％であった。
ついで、洗浄薬剤を噴霧されたのちの室内空気を、実施例３と同様に、図１に示す洗浄装置１に吸入し、洗浄した。使用した、気体洗浄用充填材および洗浄薬液は実施例３と同様とした。図１に示す洗浄装置１の排気口９から排出された空気の二酸化硫黄濃度を北川式ガス検知管で測定したが、検出されなかった。
（実施例５）
噴霧塗装工場の塗装ブースから排出される塗装ミストと有機溶剤とを含む気流の洗浄を実験した。
【０１１０】
まず、噴霧塗装工場の建物内部に、鉄製パイプで３×３×３ｍの骨格を作り、その外面に気密が保たれるようにポリエチレンフィルム（厚さ：０．１５ｍｍ）で覆いをかけ、床には受け皿を置き、中央上部には下方向に噴霧可能に３流型噴霧機の噴霧ノズルを置いた除塵ブースを設置した。噴霧ノズルは、噴霧口から５０ｃｍの位置で平均粒径が１０μｍのミストを発生できるノズルとした。 なお、除塵ブースの排気口には、二次除塵のために洗浄薬液で湿潤され気体洗浄用充填材を含む層を設け、該層を経由して、塗料中の固形分のほとんどが除塵されまだ有機溶剤ミストを含む気体を吸引するＡｌ製フレキシブルパイプ（直径：１５０ｍｍ
）が接合されている。この二次除塵のための気体洗浄用充填材を含む層は、紙粒に耐水性を付与するＢ処理を施された気体洗浄用充填材（気体洗浄用充填材Ｎｏ． Ｂ：実施例１参照）を用いて積層（厚さ：２０ｃｍ）した。また、この気体洗浄用充填材を含む層には、小型液流ポンプに嵌合した塩化ビニルチューブの先端に開けられた細孔から、洗浄薬液（下記に示す洗浄薬液ｄ）が間欠的に供給される。
【０１１１】
この除塵ブースの排気口に接続されたＡｌ製フレキシブルパイプのもう一方は、図１に示す洗浄装置１の吸気口１ａに接続されている。洗浄装置１は、ステンレス鋼製ドラム缶（内径５８０ｍｍ
×高さ８５０ｍｍ ：内容積２３０ Ｌ）を改造したもので、ふたの中央には吸気口１ａが設けられている。洗浄装置の上部には、下方向に噴霧可能に３流型噴霧機の噴霧手段（噴霧ノズル）３を設置するとともに、噴霧ノズルの下４０ｃｍの位置に気体洗浄用充填材を含む層２（
充填材の厚さ：２０ｃｍ）を水平に積層した。なお、この気体洗浄用充填材を含む層２は、気体洗浄用充填材（気体洗浄用充填材Ｎｏ． Ｂ：実施例１参照）を用いた。この気体洗浄用充填材を含む層２には、回転式散水器により洗浄薬液（下記に示す洗浄薬液ｅ）が散布され、含浸・供給され絶えず湿潤されるようになっている。また、噴霧手段３（噴霧ノズル）は、除塵ブースに設置された噴霧ノズルと同じ形式とした。
【０１１２】
洗浄装置内の噴霧手段３（噴霧ノズル）からは、気体洗浄用充填材を含む層２との空間（約０．１ ｍ^３ ）に、吸気口からの気流と並流して洗浄薬液（下記に示す洗浄薬液ｄ）が噴霧される。なお、噴霧された洗浄薬液のミストは噴射口から１５ｃｍの位置でレーザ光散乱式粒度分布測定法で測定し、平均粒径で１０μｍ
であった。洗浄薬液（洗浄薬液ｄ）が噴霧された気流は、気体洗浄用充填材を含む層で液滴化され、洗浄装置底部の洗浄薬液槽６に洗浄薬液とともに溜まる。図１に示す洗浄装置では、洗浄装置底部に溜まる液量を一定（液位：３５ｃｍ）としており、それを超えると、洗浄装置側面に設けたパイプを通し装置外の洗浄薬液貯槽７に落差を利用して流入するようになっている。洗浄薬液貯槽７に蓄えられた洗浄薬液は、液流ポンプ４ａにより供給手段４（回転式散水器）へ供給され再利用される。なお、減量した洗浄薬液は随時調整され補給される。また、洗浄薬液貯槽７の液面に浮上した塗装用の有機溶剤は比重差を利用して分液回収される。
【０１１３】
洗浄薬液ｄは、質量１ｋｇあたり、直鎖分子でアニオン性の、分子量２．０ ×１０^７ （極限粘度法）、アクリル酸が質量１ｋｇ中に１５％共重合した、ポリアクリルアミドのトリエタノールアミン塩を５ｇ
、「両親媒性溶剤」であるトリエチレングリコールジメチルエーテルを０．５ｇ、ジエチレングリコールジメチルエーテルを０．５ｇ、殺菌剤としてのヨウ素とポリビニルヒロリドンとの複合体をヨウ素換算で０．００１ｇを含む水溶液とした。
【０１１４】
洗浄薬液ｅは、洗浄薬液ｄに、有機溶剤を不完全な乳化状態とするために、さらに質量１ｋｇあたり、ＨＬＢ値が１５．０のポリオキシエチレンソルビタンモノステアレートを０．２ｇ
を、混合した水溶液とした。
このような除塵ブースと洗浄装置１とを用いて、除塵ブース入口での送風量を３ｍ^３ ／分に調節して、塗装ブースから排出される気体を洗浄した。
【０１１５】
その結果、まず除塵ブース内で洗浄薬剤を噴霧すると、突然晴れた空から雪が降るように、いままで目視できなかった塗装ミストが固体状で床に沈降するのが観察された。
除塵ブースで洗浄薬液を噴霧された気体はついで、洗浄装置１内で噴霧され、気体洗浄用充填材を含む層で液滴化されて、洗浄装置の排気口から排気された。排気された気体の臭気濃度を実施例１と同様な方法で測定した。その結果、臭気濃度は１１００（希釈倍率）であった。同様な方法で測定した、塗装ブースから排気された気体の臭気濃度が２１０００
（希釈倍率）であることからも、本発明の洗浄システムは有効であることがわかる。
【０１１６】
なお、除塵ブースでの洗浄薬液の噴霧を、２流体噴霧機を利用して、噴霧ミストの平均粒径を５０μｍとした場合も実験した（比較例）が、一定噴霧量当たりの床への沈降量は本発明例の約１５％であった。
（実施例６）
図１に示す洗浄装置を用いて、バイオガスに多量に含まれる硫化水素の除去について、実験した。
【０１１７】
なお、洗浄装置１内の、気体洗浄用充填材を含む層２は、気体洗浄用充填材として、紙粒に耐水性と硬さを付与するＣ処理を施した気体洗浄用充填材Ｎｏ．
Ｃ（実施例１参照）を用い、この気体洗浄用充填材を厚さ：２５ｃｍに積層した層を２段構成し、気液接触が２倍となるようにした。
また、気体洗浄用充填材を含む層２に含浸または供給する洗浄薬液は、次に示す洗浄薬液ｆとした。
【０１１８】
洗浄薬液ｆは、質量で、「両親媒性溶剤」であるトリエチレングリコールジメチルエーテルを２％、カセイソーダを１０％、ヨウ素とポリビニルヒロリドンとの複合体をヨウ素換算で０．０１％を、混合・溶解した水溶液とした。
吸入ブロワー１ｂで吸引した空気に、液化硫化水素入りボンベから減圧弁と流量計とにより一定量の硫化水素を混入し、洗浄装置１の吸気口１ａに吹き込んだ。なお、噴霧手段３（噴霧ノズル）からの洗浄薬液の噴霧を行わなかった。
【０１１９】
送風量は３ｍ^３ ／分に設定して、圧力損失を３０ｍｍ ａｑ として、実験した。送風開始から１０分後に、吸気口１ａでの硫化水素濃度を、北川式ガス検知管で測定したところ、４０００ｐｐｍ
であった。一方、洗浄装置の排気口９で同様に硫化水素濃度を測定したが、検知できなかった。実験開始から３時間まで１時間ごとに、同じ分析を行ったが、洗浄装置の排気口９での硫化水素は検出されなかった。
【０１２０】
しかし、３ 時間４５分経過した時点で、硫化水素臭が装置の周辺に強く漂い始めたので、危険防止のため硫化水素の送入を中止し、予備の洗浄薬液２ｋｇを投入し、完全に硫化水素が排気口から検出されなくなるまで、送風のみで運転した。一定時間後に、硫化水素の除去ができなくなったのは、洗浄薬液の中和反応当量がゼロとなったためで、バイオガスのような高濃度の硫化水素を含む場合には、使用した洗浄薬液は不適であり、脱硫能力を大幅に向上した薬液とする必要があることが判明した。
（実施例７）
実施例６と同じ、気体洗浄用充填材を含む層を有する洗浄装置（図１）を使用して、硫化水素ガスの除去を試みた。
【０１２１】
吸入ブロワー１ｂで吸引した空気に、液化硫化水素入りボンベから減圧弁と流量計とにより一定量の硫化水素を混入し、さらに、亜硫酸ガスを、液化亜硫酸ガスボンベから硫化水素との反応等量の９５％に相当する１８００ｐｐｍ
を、亜硫酸ガス供給口８ａから吹き込んだ。なお、洗浄装置内の噴霧手段３からの洗浄薬液の噴霧は行わなかった。
【０１２２】
洗浄薬液としては、「両親媒性溶剤」であるトリエチレングリコールジメチルエーテルを２％、カセイソーダを１０％、トリエタノールアミンを５％、塩析剤としての塩化ナトリウムを３％、ヨウ素とポリビニルヒロリドンとの複合体をヨウ素換算で０．０１％を、混合・溶解した水溶液とした。洗浄薬液は、５０ｋｇ用意した。送風開始から１、３、４、７、１０、１５時間後に、それぞれ北川式ガス検知管で硫化水素、亜硫酸ガスの濃度を洗浄装置の排気口９で測定した。その結果、いずれも、硫化水素、亜硫酸ガスは検出されなかった。なお、図１の洗浄装置の底部に溜まる洗浄薬液は、運転開始前から比べると、白濁した硫黄を含むスラリーに変化し、しかもかなりの硫黄が沈殿している状況が見られた。この硫黄分は、通常の凝集沈殿、洗浄、濾過法で容易に分離回収ができ、亜流酸ガスの原料として再利用可能である。なお、洗浄薬液も再利用できることを確認した。
【０１２３】
【発明の効果】
本発明によれば、従来、汚染気体から除去することが困難であった、悪臭を伴ったり有害であったりする、分子状やエアロゾル状等の汚染物質、あるいはそれらの混合した汚染物質、あるいはさらに疎水性の汚染物質等を、簡便で、かつ安全にしかも完全に一括して除去でき、また、使用する動力、用水、薬剤等も少なくてすみ、産業上格段の効果を奏する。また、本発明によれば、有害な汚染物質を環境へ漏洩させることなく、汚染気体の洗浄を行うことができ二次災害発生の危険性を低減するという効果もある。
【図面の簡単な説明】
【図１】本発明の汚染気体の洗浄装置の一例を模式的に示す断面図である。
【符号の説明】
１ 洗浄装置
１ａ 吸気口
１ｂ 吸入ブロアー
１ｃ 配管
２ 気体洗浄用充填材を含む層
２ａ 液滴
２ｂ 充填材支持枠
２ｃ 気体洗浄用充填材
３ 噴霧手段
３ａ ミスト（噴霧）
４ 供給手段
４ａ 液流ポンプ
５ 汚染気体
６ 洗浄薬液槽
６ａ１ 、６ａ２ 、６ａ３ 配管
６ｂ１ 、６ｂ２ 、６ｂ３ バルブ
６１ 洗浄薬液槽
６１ａ 加圧用コンプレッサー
７ 洗浄薬液貯槽
７ａ 汚染物質
７ｂ１ 、７ｂ２ 配管
７ｃ１ 、７ｃ２ バルブ
８ 亜硫酸ガス供給口、８ｂ 配管
９ 、９ａ 排気口[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to the removal of gaseous pollutants in gas, and in particular, is contained in the air and gives unpleasant feelings to human livestock, or is further inhaled from respiratory organs, mucous membranes such as eyes and nose, and skin. Contains molecular or aerosol gases that can penetrate into the body through contact, etc., cause fatal and / or acute, subacute or chronic health problems, and can cause serious environmental pollution when accumulated in the environment. Pollutant gas cleaning system that removes gaseous pollutants and cleans the airAnd cleaning method of pollutant gas using this cleaning systemAbout.
[0002]
[Prior art]
  Conventionally, as a method for cleaning pollutant gas, a cleaning method determined mainly for each type and concentration of pollutants has been employed.
  For example, molecular pollutants such as harmful gases and malodorous gases have a particle size in the range of about 0.0003 to 0.0005 μm, and removal methods include a direct combustion method and a porous material such as activated carbon. There are methods of adsorption, methods of decomposing by ozone, titanium oxide and light, microorganisms and enzymes, methods of changing to other substances by chemical reaction such as oxidation, neutralization, metathesis, addition etc. with aqueous chemicals etc. It has been selected and used accordingly.
[0003]
  For example, in paint factories, gravure printing factories, plastic molding factories, etc., paint mist, solvents, unpolymerized unsaturated ethylene compounds, various additives, and other harmful substances and malodorous substances are discharged at high concentrations in the air. Conventionally, air has been purified using a combustion method or a method of adsorption with activated carbon. However, molecular organic substances can be completely removed by these methods. However, in the case of aerosol-like substances such as paint mist, there is a drawback in that burnout deposits on the combustion plate and the combustion catalyst or clogging of the activated carbon occurs. There was a problem that management and maintenance were not easy.
[0004]
  In addition, recently, the plan is to use so-called biogas as fuel gas (methane gas) generated by microbial fermentation of biomass such as garbage, livestock dung and urine, sawdust, waste wood such as garden trees and thinned wood, etc. Is underway. These biogases often accompany high concentrations of hydrogen sulfide, alkyl mercabtan with strong malodor, methyl sulfide, suspected harmful bacteria and their spores. At present, only the adsorption method is used, and the contaminants are not completely removed.
[0005]
  In addition, aerosol pollutants have a particle size in the range of about 0.005 to 50 μm, viruses, bacteria, fungi and their spores; fire smoke, oil, cigarette smoke, etc .; dust, fly ash, colloidal Silica, pulverized coal, metal powder; pollen and the like can be mentioned. At present, it is difficult to remove from the air. As a method for removing these aerosol-like pollutants from the air, a dust collection method using gravity, centrifugal force, inertia force, etc., an electrostatic dust collection method, a filtration dust collection method, etc. have been selected according to the purpose. Have been used. In particular, a filtration dust collection method using a bag filter, an air filter, a ceramic filter or the like has been mainly employed. However, the minimum particle size of contaminants that can be removed by these methods is about 0.01 μm, and fine aerosol contaminants such as spores, viruses and colloidal silica with particle sizes smaller than this can be completely removed. Not.
[0006]
  Moreover, there is a cleaning tower method as a method for removing contaminants in the gas by bringing the gas and the chemical solution into gas-liquid contact, and various apparatuses and various cleaning chemical solutions have been proposed and used. For example, a gas dispersion type that blows gas containing contaminants into the chemical solution, a liquid film type chemical solution dispersion type that puts plastic fillers of various shapes into contact with the chemical solution and gas containing contaminants, and a cyclone scrubber There is a droplet type chemical liquid dispersion type in which a gas containing a contaminant is brought into contact with a sprayed chemical liquid, and it is said that molecular contaminants can be removed by using a chemical liquid according to the purpose. However, the removal rate (cleaning rate) of molecular contaminants by these methods is at most about 70%, and further improvement in the removal rate (cleaning rate) has been demanded.
[0007]
  In response to such a request, the applicant of Patent Document 1 includes an aqueous chemical solution tank and a layer containing paper grains impregnated with the aqueous chemical solution, and passes contaminated gas through the aqueous chemical solution tank, and then impregnates the aqueous chemical solution. We proposed a method for cleaning pollutant gas that removes pollutants in the gas through a layer containing paper particles. In the technique described in Patent Document 1, paper particles coated with or impregnated with a thermosetting resin and / or a fiber cross-linking agent and cured and / or cross-linked are used, and (a) an oxidizing agent, ( b) an acidic or alkaline substance, (c) a buffering substance, (d) a betaine compound, (e) glyoxal and its polyol adduct, (f) a water-soluble polyol having 10 or less carbon atoms, (g) sulfur dioxide And / or one or more selected from alkali metal sulfites and (h) bactericides.
[0008]
[Patent Document 1]
JP 2001-149739 A
[0009]
[Problem to be Solved by the Invention]
  In the technique described in Patent Document 1, in order to impart water resistance and shape retention when wet by a chemical solution to a paper grain to be used, a thermosetting resin and / or a fiber crosslinking agent is applied or impregnated. Yes. In the technique described in Patent Document 1, a wide range of molecular and aerosol-like pollutants can be obtained by using an aqueous chemical liquid having chemical reactivity in a scrubber using such water-resistant paper grains as a filler. The pollutant gas can be cleaned.
[0010]
  However, in the technique described in Patent Document 1 that uses paper grains coated or impregnated with a thermosetting resin and / or a fiber cross-linking agent, the paper grains swell and collapse under their own weight when used for a long period of time. , There is a problem that the gap through which the gas to be processed passes decreases and pressure loss increases, and that when thermosetting resin, especially melamine resin is used, paper grains become hydrophobic and it may be difficult to absorb aqueous chemicals. There has been a demand for further improvement in the aqueous chemical solution absorbability (hydrophilicity) of the paper grains used and the shape maintenance after long-term use.
[0011]
  Further, in the technique described in Patent Document 1, the paper grain to be used behaves almost neutral in water, but the paper grain has a weak acidity, so it is relatively easy to capture basic contaminants. Entrapment of hydrophobic, volatile, weakly acidic contaminants remained problematic. In addition, pollutants include hydrophobic gas molecules, a mixture of many kinds of molecules such as grilled meat odor, and aerosols, or fine dust such as colloidal silica and smoke, viruses, etc. In such a case, the technique described in Patent Document 1 still has a problem that it is difficult to remove completely.
[0012]
  In addition, since biogas often accompanies high-concentration hydrogen sulfide, alkyl mercabtan with strong malodor, methyl sulfide, suspected harmful bacteria and their spores, it is described in Patent Document 1. Even with the technology, it has been difficult to completely remove contaminants in biogas.
  Also, in a semi-enclosed space such as in a high-rise building, subway car, or station premises, if a lethal harmful gas or aerosol is generated or a fire occurs and a large amount of smoke is generated, a large amount of air is discharged. It is common to perform methods such as blowing air, exhausting smoke, or spraying water. However, such a method cannot remove harmful gases, smoke, and the like from the treated gas (gas), and there is a concern about the occurrence of secondary disasters caused by these pollutants.
[0013]
  In this way, rapid removal of fire smoke and complete removal of deadly harmful gases and aerosols, or spores such as bacteria and fungi, viruses, etc. are currently established technologies. is not.
  The present invention solves such problems of the prior art, and is pollutant such as molecular or aerosol, mixed with pollutants, or more hydrophobic, which is accompanied by bad odor as described above or harmful. It is an object of the present invention to propose a cleaning system and a cleaning method for pollutant gas that can effectively and easily remove pollutant from a pollutant gas containing volatile pollutants and clean the gas.
[0014]
[Means for Solving the Problems]
  Means for solving the problems of the present invention are as follows.
[0015]
(1) Has a layer containing a gas cleaning fillerAnd a cleaning chemical supply means for supplying a cleaning chemical to the layer containing the gas cleaning filler.And a layer containing the gas cleaning fillerCleaning chemical solution supply means for supplying cleaning chemical solutionUpstream ofIn addition to the cleaning device or separately from the cleaning device, spraying means with the same or different cleaning chemical liquid is provided, and further upstream of the spraying means.A pollutant gas inlet is provided, and the pollutant gas introduced from the inlet isAfter spraying the cleaning chemical by the spraying meansA contaminant gas cleaning system for cleaning contaminant gas by passing it through a layer containing the gas cleaning filler,The spraying means is a spraying means capable of spraying the cleaning chemical liquid as a mist having an average particle size of 30 μm or less,The gas cleaning filler is subjected to the following A to C treatment on paper grains mainly composed of fiber fibers.
                              Record
A treatment: One or two kinds of polyvinyl alcohol and solubilized chitosan, and a fibrous fiber cross-linking having 2 or more methylol groups or methoxymethyl groups in which an active hydrogen atom is not bonded to a nitrogen atom in the molecule One or more of the agents and acidcatalystOr further impregnating an aqueous solution containing methyl alcohol as an essential component, followed by drying and heat treatment to impart water resistance and hardness.
[0016]
B treatment: A treatment for impregnating an aqueous solution containing an acid catalyst as an essential component, drying while leaving moisture, and reacting gaseous formaldehyde at 0 to 100 ° C. to impart water resistance.
C treatment: impregnated with one or two of polyvinyl alcohol and solubilized chitosan and an aqueous solution containing an acid catalyst as an essential component, dried with leaving moisture, and gaseous formaldehyde at 100 ° C. or lower A process of reacting and imparting water resistance and hardness.
After impregnating phosphoric acid or an aqueous solution containing phosphoric acid and urea, and performing a pretreatment of drying and heat treatment at a temperature of 130 to 170 ° C., the following AC treatments are performed: It is composed of paper grains subjected to one kind of treatment selected from the above, and the layer containing the gas cleaning filler comprises at least one kind of gas cleaning filler obtained by performing each of the above treatments, Laminating, bagging, and upper and lower two surfaces are constituted by one or two or more means of filling an air-permeable cartridge, and the layer containing the gas cleaning filler has a boiling point. No cleaning chemical solution containing a water-soluble amphiphilic organic compound at 150 ° C. or higher is impregnated or supplied.And a cleaning chemical solution tank in which the cleaning chemical solution that has passed through the layer containing the gas cleaning filler is stored so that the level of the cleaning chemical solution is lower than the layer containing the gas cleaning filler, and A cleaning chemical solution storage tank, a water tank or a pollutant processing tank for separating contaminants that have floated in the cleaning chemical solution tank is provided.A pollutant gas cleaning system.
[0017]
(2) Contaminating gas is introduced into a cleaning system comprising a cleaning device having a spraying means with cleaning chemicals and a layer containing a gas cleaning filler, or into a cleaning system having spraying means separately from the cleaning device and the cleaning device. And a cleaning method for contaminated gas, in which the cleaning gas is sprayed by the spraying means and then passed through the layer containing the gas cleaning filler to perform cleaning, wherein the gas cleaning filler is a fibrous element. The following AC treatment is applied to paper grains mainly composed of fibers.
A treatment: one or two of polyvinyl alcohol and solubilized chitosan, and a fibrous fiber having 2 or more methylol groups or methoxymethyl groups in which no active hydrogen atom is bonded to the nitrogen atom in the molecule A treatment that impregnates an aqueous solution containing one or more of crosslinking agents, an acid accelerator, or further methyl alcohol as essential components, and performs drying and heat treatment to impart water resistance and hardness.
B treatment: impregnated with an aqueous solution containing an acid accelerator as an essential component, dried to leave moisture, and added gaseous formaldehyde to 100
A process of reacting at a temperature of ℃ or less to impart water resistance.
C treatment: impregnated with one or two of polyvinyl alcohol and solubilized chitosan and an aqueous solution containing an acid accelerator as an essential component, dried to leave moisture, and added gaseous formaldehyde to 100
A treatment that gives water resistance and hardness by reacting at ℃ or below.
After impregnating one treatment selected from the above or an aqueous solution containing phosphoric acid or phosphoric acid and urea, and performing a pretreatment for drying and heat treatment at a temperature of 130 to 170 ° C., the above-mentioned AC 1 type of gas cleaning filler obtained by applying each of the above treatments to the layer containing the gas cleaning filler, which is made of paper particles subjected to one type of processing selected from the processing. The above is constituted by one or two or more means of laminating, bagging and filling the air-permeable cartridge on the upper and lower surfaces, and has a boiling point of 150.
Do not impregnate or supply cleaning chemicals that contain water-soluble amphiphilic organic compoundsFurther, the cleaning chemical solution is passed through the layer containing the gas cleaning filler and accumulated in the cleaning chemical solution tank, and then the contaminant floating in the cleaning chemical solution tank is stored in the contaminant treatment tank, and the contamination Further isolate the substanceA method for cleaning a pollutant gas.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
  The contaminated gas cleaning system of the present invention comprises a cleaning device 1 having at least one layer 2 containing a gas cleaning filler. The gas cleaning filler 2c is preferably a treatment that imparts water resistance, shape retention when wet, hardness, or further ion exchange to paper grains mainly composed of delignified fiber fibers. A cleaning chemical solution containing a water-soluble amphiphilic organic compound (hereinafter also referred to as “amphiphilic solvent”) is supplied to the layer 2 containing the gas cleaning filler. The impregnated or supplied by the means 4, and the contaminated gas is sucked from the contaminated gas intake port 1a provided on the upstream side of the layer 2 containing the gas-cleaning filler through the suction blower 1b and the pipe 1c. The polluted gas 5 is passed through the layer 2 containing, and the polluted gas is cleaned.
[0019]
  In the cleaning system of the present invention, the cleaning chemical solution spraying means 3 is provided in the cleaning apparatus 1 having the layer 2 containing the gas cleaning filler described above or separately from the cleaning apparatus 1. When the spraying means 3 is provided in the cleaning apparatus 1, the spraying means 3 is disposed on the upstream side of the layer 2 containing the gas cleaning filler, and the compressed gas 61 is supplied from the cleaning chemical tank 61 to the contaminated gas 5.
After spraying the cleaning chemical solution supplied by the mist 3a with an average particle size of 30 μm or less, after trapping and conjugating the pollutant in the polluted gas, the sprayed polluted gas passes through the layer 2 containing the gas cleaning filler. Let FIG. 1 shows an example in which the spray means 3 is arranged in the upstream side (here, the upper part) of the layer 2 containing the gas cleaning filler in the cleaning apparatus 1.
[0020]
  When the spraying means 3 is installed in the cleaning device 1 on the top of the layer 2 containing the gas cleaning filler, the sprayed cleaning chemical mist 3a is converted into droplets 2a in the layer 2 containing the gas cleaning filler. There is an advantage that the pollutant in the pollutant gas can be easily separated and discharged. Moreover, if it is high temperature contamination gas, there exists an advantage that the mist of the sprayed cleaning chemical | medical solution can be cooled and made into droplet by the layer 2 containing the gas cleaning filler. When droplets are formed in the layer 2 containing the gas cleaning filler, the cleaning chemical solution is supplied to the layer 2 containing the gas cleaning filler by the supply means 4 via the liquid flow pump 4a, and the adhered contaminants are removed. Washing with the cleaning chemical solution, and cleaning the lower part (downstream) of the cleaning apparatus 1 from the layer 2 containing the gas cleaning filler, with the liquid level positioned lower than the layer 2 containing the gas cleaning filler Dropped into the chemical solution tank 6, the cleaning chemical solution storage tank 7 or the water tank (not shown), or further from the cleaning chemical solution storage tank 7 to the pipe 7 b 1
Further, it is possible to separate and recover by putting into a continuous processing apparatus (not shown) via the valve 7c1. Note that the cleaning chemical solution for washing away the attached contaminants may be the same as the sprayed cleaning chemical solution, or may be further added with a chemical adapted for the treatment of the contaminants, or may have other prescriptions. Unlike FIG. 1, the cleaning chemical solution tank 6 or the water tank may be provided in the lower part without providing the cleaning chemical solution tank 6.
  Further, when the spray means 3 is provided below the layer 2 containing the gas cleaning filler in the cleaning apparatus 1 or separately from the cleaning apparatus 1, the spray mist that traps and conjugated contaminants in the contaminated gas. Is allowed to settle on the bottom or floor of the apparatus, and then the contaminated gas containing the remaining mist is passed through the layer 2 containing the gas cleaning filler, and the remaining mist is removed to allow the gas to flow into the system.
It is preferable to discharge outside (apparatus). Further, the system is passed through the layer 2 containing the gas cleaning filler impregnated or supplied with the cleaning chemical solution provided separately from the layer 2 containing the gas cleaning filler in the cleaning apparatus 1.
You may discharge outside (apparatus).
[0021]
  The spraying means 3 for the cleaning chemical may be any sprayer that can measure the cleaning chemical liquid at a position 15 cm from the injection port by the laser light scattering particle size distribution measurement method and reduce the average particle size to 30 μm or less. Any type sprayer may be used, and its method is not particularly limited.
  When the average particle size of the sprayed cleaning chemical liquid particles exceeds 30 μm, the particles are too large and fall quickly, so there is a low probability of colliding with the pollutants in the polluted gas, and the pollutants cannot be completely captured. . In order to slow down the sedimentation rate of cleaning chemical liquid particles and efficiently capture and remove contaminants, the sprayed cleaning chemical liquid particles need to have an average particle size of 30 μm or less. In addition, Preferably it is 20 micrometers or less, More preferably, it is 10 micrometers or less. For example, when the velocity of the airflow is 0 (stationary state), when the average particle size is 10 μm, the settling velocity is about 22 times slower than when 50 μm.
[0022]
  In the cleaning system of the present invention, the liquid level is lower than that of the layer 2 containing the gas cleaning filler, separated from the layer 2 containing the gas cleaning filler downstream (or lower part) of the cleaning device 1 described above. A cleaning chemical solution tank 6 provided as a position, or a cleaning chemical solution storage tank 7 or a water tank (not shown) connected further through the cleaning chemical solution tank 6 and a pipe 6a2 and a valve 6b2, or further from the cleaning chemical liquid storage tank 7 to a pipe 7b1 and a valve 7c1 is provided with a continuous pollutant treatment tank (not shown).Is.            By disposing the cleaning chemical liquid storage tank 7 or the water tank downstream of the cleaning chemical liquid tank 6, the cleaning chemical liquid containing droplets of the pollutant is allowed to flow on the liquid level of the cleaning chemical liquid storage tank 7 or the water tank. There is also an advantage that separation is facilitated using a specific gravity). Further, by disposing the pollutant treatment tank separately from the cleaning device, it is possible to detoxify toxic pollutants and to prevent the occurrence of secondary disasters.
[0023]
  In the cleaning system of the present invention, the material of the cleaning device to be used is not particularly limited, but depending on the type of contaminants, corrosion-resistant materials such as polypropylene, polyvinyl chloride, acrylic resin, and stainless steel can be used. It is preferable to do.
[0024]
  First, the layer containing the gas cleaning filler used in the cleaning system of the present invention will be described.
(1) Layer containing a gas cleaning filler
  In the present invention, the cleaning apparatus 1 has a layer 2 containing a gas cleaning filler. The gas cleaning filler 2c is preferably made of paper grains that are delignified or formed into a lump with fiber fibers pretreated with liquid ammonia as the main component. The paper grain is preferably produced by dripping water droplets containing a thin paste into a container that rotates a dry powder of the fiber at a high speed, and drying it so that the fiber is entangled. In the present invention, the material of the fiber element fiber is not particularly limited, but cellulose fiber such as pulp, cotton, rayon, etc., hydrophilic fiber such as protein fiber, polyvinyl alcohol, etc. Can also be suitably applied. In addition, you may mix another substance to such an extent that paper fine granulation property and adsorption | suction and a water retention function are not impaired. Further, the shape of the paper grain is not particularly limited, but it is preferable to use a spherical shape, an elliptical shape, a cylindrical shape, and the like, and their modifications. The size of the paper grain is preferably about 3 to 12 mm.
[0025]
  Even if the water-resistant fiber of the paper grain is subjected to water-resistant processing, not only the inside but also the surface layer is a hydrophilic polymer compound, so it absorbs water well to the surface layer of the paper grain and the fine structure inside. On the other hand, it has no affinity for animal oils, vegetable oils, mineral oils, and the like, and has a specific gravity lower than that of water. Paper grains once absorbed do not absorb these oils. For this reason, on the surface of the paper grain subjected to the water resistance treatment described below, the attached oil is dripped quickly, which is suitable as a filler for gas cleaning.
[0026]
  The gas cleaning filler used in the present invention is a paper that has been subjected to one treatment selected from the following A treatment to C treatment for imparting water resistance and hardness to the above-mentioned paper grains. It consists of grains.
(I) A processing
  In the A treatment, active hydrogen atoms are bonded to the nitrogen atom in the molecule and one or two kinds of chitosan solubilized with a monovalent acid such as polyvinyl alcohol, nitric acid and hydrochloric acid on the paper grain. At least one kind of fibrous fiber cross-linking agent having 2 or more methylol groups or 2 or more methoxymethyl groups, and an acidcatalystOr further impregnating an aqueous solution containing methyl alcohol as an essential component, followed by drying and heat treatment to impart water resistance and hardness.
[0027]
  One or two of chitosan solubilized with polyvinyl alcohol and a monovalent acid contained in the aqueous solution used in the treatment A is a thermosetting resin (melamine resin) described in Patent Document 1. Thus, without sacrificing water absorption, the paper grain can be imparted with a hardness that is not crushed even when used for a long time under moisture. One or two of chitosan solubilized with polyvinyl alcohol and a monovalent acid is 0.5% by mass after drying with respect to the total amount of paper grains.
It is preferable to be impregnated in an aqueous solution so as to adhere to ~ 1.5% paper grain. If it is less than 0.5%, the above-mentioned effects are not observed. On the other hand, if it exceeds 1.5%, the viscosity of the aqueous solution increases and the processing efficiency decreases. The polyvinyl alcohol and chitosan used are preferably high molecular weight product numbers. Polyvinyl alcohol has the advantage that if a completely saponified type is used, weight loss due to hydrolysis does not occur even when a strong acidic or strongly basic chemical solution is used.
[0028]
  As a fiber-fiber cross-linking agent, one or more of those having 2 or more methylol groups or methoxymethyl groups in which active hydrogen atoms are not bonded to nitrogen atoms in the molecule are contained. N, N'-dimethylol is used as such a fibrous fiber cross-linking agent.
Examples thereof include dihydroxyethylene urea (hereinafter also referred to as DMMHEU). The fiber-fiber cross-linking agent is preferably contained in the aqueous solution and impregnated into the paper grains so that 1% to 2% is adhered in terms of mass% after drying with respect to the total amount of the paper grains. Other examples of the fibrous fiber cross-linking agent having 2 or more methylol groups or methoxymethyl groups in which no active hydrogen atom is bonded to the nitrogen atom in the molecule include ethylene urea, propylene urea, uron, methyl triazine, dimethyl carbamate, etc. Dimethylolated products such as acetylene ureine tetramethylolated products can also be used.
[0029]
  acidcatalystAs such, ammonium chloride, p-toluenesulfonic acid, methanesulfonic acid and the like are suitable. acidcatalystWhen the paper grain is impregnated in the aqueous solution together with the crosslinking agent and then completely dried and heat-treated, it promotes the OH groups and dehydrated ether bonds of the fiber fibers and improves the water resistance and shape maintenance of the paper grain. Contributes to improvement. The acid catalyst is a fibrous fiber cross-linking agent.
The amount is preferably about 5 to 10 parts by weight based on 100 parts by weight (in terms of anhydride).
[0030]
  Moreover, you may substitute the water | moisture content of a part of aqueous solution with methyl alcohol. By adding methyl alcohol preferably 10 to 50% of the moisture mass, the paper grain surface layer after drying and heat treatment becomes hard, water resistance and hardness are improved, and resistance to crushing when wet is increased. . This is because during drying, methyl alcohol with a low latent heat of vaporization and easily evaporated, and a fibrous fiber cross-linking agent (DMMHEU) that also dissolves in methyl alcohol migrates from the inside of the paper grain to the surface layer, while a polymolecular having a high molecular weight. It is considered that vinyl alcohol and chitosan do not enter the fine structure of the paper fiber and remain on the surface, so that high-density crosslinks are formed on the surface of the paper grain. Further, when methyl alcohol is added, the drying speed is increased and the drying time can be remarkably shortened, so that there is an advantage that productivity can be greatly improved.
[0031]
  In the treatment A, an aqueous solution containing the above-mentioned chemical as an essential component is impregnated into paper grains, followed by drying and heat treatment. The heat treatment is performed at 120 ° C. or higher, preferably 135 ° C. or higher, 160
It is preferable to set it as below ℃. When heat treatment is performed after drying, the polyvinyl alcohol and the fiber are easily dehydrated by the fiber cross-linking agent to form an ether condensation cross-link and become water-insoluble, thereby improving the water resistance of the paper grain. In addition, the amino group of chitosan and the fibrous fiber cross-linking agent (DMMHEU) are 120 times after heat treatment after drying.
A dehydration condensation is performed at around 0 ° C. to form a cross-link by methylene condensation, and a hydrophilic and water-insoluble film is formed on the fiber surface of the paper grain. As a result, the paper grains become hard and can withstand use (crushing) under long-term wet conditions. In addition, the amino group remaining uncrosslinked of chitosan is also given ion exchange properties for once capturing hydrophobic and weakly acidic contaminants that could not be captured using a strongly basic detergent solution.
(B) B processing
  B treatment uses acid on the paper grain.catalystIs impregnated with an aqueous solution containing as an essential component, preferably 20 to 100% leaving moisture and dried to give 100% gaseous formaldehyde.
This is a treatment for imparting water resistance by reacting at a temperature not higher than ° C.
[0032]
  Acid added to aqueous solution by B treatmentcatalystSuitable examples include ammonium chloride, p-toluenesulfonic acid, methanesulfonic acid, sulfurous acid gas, zinc chloride, hydroxyzinc chloride, hydroxyaluminum chloride, sulfamic acid, and hydrochloric acid.
In the B treatment, the above-mentioned acid is applied to the paper grain.catalystIs impregnated with an aqueous solution containing the essential components of the product, dried so that the water content is adjusted to 20 to 100% of the paper grain mass, and preferably 100% of gaseous formaldehyde is generated by heating paraformaldehyde.
After contacting and reacting at a temperature of ℃ or less to form a crosslink, washing is performed with water, remaining unreacted harmful formaldehyde is removed, and then dried. Thereby, the paper grain becomes a paper grain having sufficient water resistance, but the hardness at the time of moisture absorption is slightly insufficient. In the B treatment, the acid described above is used.catalystBefore impregnating with an aqueous solution containing as an essential component, the paper grains may be treated with liquid ammonia to increase the fiber adsorptivity. The treatment with gaseous formaldehyde is preferably performed in a sealed space.
(C) C treatment
  In the C treatment, one or two kinds of chitosan solubilized with polyvinyl alcohol and a monovalent acid, and acidcatalystIs impregnated with an aqueous solution containing as an essential component, preferably 20-100
% Of moisture is dried, and then, gaseous formaldehyde generated by heating paraformaldehyde is preferably reacted at 100 ° C. or less to impart water resistance and hardness.
[0033]
  The content of one or two of polyvinyl alcohol and chitosan in the aqueous solution used in the C treatment is the same as the solution used in the A treatment, and the acidcatalystThe content of is preferably the same as the liquid used in the B treatment. In the C treatment, it is not necessary to add methyl alcohol to the aqueous solution as in the A treatment.
In the C treatment, the above-mentioned aqueous solution is impregnated into the paper grain, and then the drying and the gaseous formaldehyde treatment are performed in the same manner as in the B treatment. By such C treatment, a paper grain having sufficient water resistance and hardness can be obtained.
[0034]
  B treatment and C treatment are disclosed in JP-A-51-72698, JP-A-51-49998, JP-A-5-59664, JP-B-6-102865.
You may divert the dimensional stabilization process for fiber filaments, such as cotton, described in Japanese Unexamined Patent Publication No. 8-127962.
  Moreover, it is preferable to perform the process for providing ion exchange property to the paper grain used for this invention as a pre-process, before giving 1 process chosen from above-mentioned A process-C process. .
[0035]
  The treatment for imparting ion exchange is carried out by impregnating a paper grain with phosphoric acid or an aqueous solution containing phosphoric acid and urea, followed by drying and heat treatment at a temperature of 130 to 170 ° C. It is the process which forms a phosphate fiber. In addition, 30 to 40% of water may be replaced with methanol by mass.
  This processing is an application of the techniques described in British Patent No. 604,197 and US Pat. No. 2,482,755. British Patent No. 604,197
No. 2,482,755 discloses a technique for imparting water resistance and fire resistance to a cotton fabric by absorbing the phosphoric acid in a cotton fabric and drying it, followed by heating to 130 ° C. to 170 ° C. It is. By this method, the fiber is phosphorylated. Instead of cotton, with paper grain, the dry mass of paper grain
The present inventors have confirmed that when an aqueous solution diluted with about 6 to 9% phosphoric acid is used, esterification can be performed in the same manner as in cotton fabric. In addition, the present inventors impregnated an aqueous solution in which urea is further added in an equimolar to 2-fold molar amount of phosphoric acid to phosphoric acid, and then 130
It has also been confirmed that a mono-substituted ammonium phosphate of acidic fiber is obtained in a yield of almost 100% by heating at a temperature of from about 170 ° C. to about 170 ° C. for about 30 minutes. Note that the phosphoric acid concentration in the pretreatment liquid is preferably 6 to 12% by mass. Moreover, when urea is further contained in addition to phosphoric acid, it is preferable to make urea into the aqueous solution which added equimolar-2 times mole of phosphoric acid.
[0036]
  Although this phosphate group is completely water resistant, there is strong ion exchange, so when washed with chemicals or water, it binds to hard water or ions such as calcium or sodium in chemicals, and fire resistance is lost. It has a typical cation exchange property that restores the fireproofing property when washed with. Giving such properties to the paper grain is very effective in capturing hydrophobic and weakly basic contaminants. When any one of the above-described A to C treatments is performed after such pretreatment, the paper grain can be simultaneously imparted with excellent water resistance, high hardness when wet, and ion exchange properties.
[0037]
  The layer containing the gas cleaning filler is formed by laminating one or more kinds of gas cleaning fillers, which are paper grains obtained by performing the above-described various treatments, in the cleaning apparatus. (2) It is preferable to use one or two or more means of bagging, and (3) filling the air-permeable cartridge on the upper and lower surfaces. In addition, it is preferable that the layer 2 containing the gas cleaning filler is supported in a breathable support frame 2b such as a wire mesh and disposed in the cleaning apparatus. The layer 2 containing the gas cleaning filler thus configured is constantly impregnated or supplied with the cleaning chemical by the supply means 4 and becomes a layer wetted by the cleaning chemical. Thereby, the layer containing the gas cleaning filler is
(1) Function as a medium that allows chemical reactions between gaseous pollutants and cleaning chemicals to proceed with high efficiency,
(2) Demist function to prevent discharge of contaminants captured by cleaning chemicals to the outside of the device,
(3) Function as a cooler and demisting material that recovers pollutants by cooling / dropping high-temperature airflow containing water-insoluble organic solvents and oily smoke as pollutants,
Will have.
[0038]
  The height of the layer containing the gas cleaning filler in the cleaning system of the present invention is not particularly limited, and can be appropriately set according to the type and amount of the contaminant contained in the contaminated gas to be cleaned.
  Gas cleaning devices are classified into a liquid dispersion type in which a chemical solution is sprayed and brought into contact with the gas, and a gas dispersion type in which a gas is ejected into the cleaning chemical solution, depending on the contact method between the gas and the cleaning chemical solution. However, the cleaning device in the cleaning system of the present invention is a gas dispersion type because the layer containing the gas cleaning filler is impregnated with the cleaning chemical solution and brought into contact with the contaminated gas, and the cleaning chemical solution is a gas in the cleaning device. Since it is distributed evenly over the entire surface of the cleaning filler (paper grain), it is also a liquid dispersion type. For this reason, the cleaning device in the cleaning system of the present invention has more reaction opportunities than the conventional plastic filler, and of course, the gas-liquid is similar to or more than the technique described in Patent Document 1 as compared with the conventional plastic filler. The contact rate is much higher than before, and this effect is sustained over a long period of time.
[0039]
  The cleaning rate of a gas cleaning device is determined by the synergistic product of the gas-liquid contact rate unique to the device and the reaction rate between the cleaning chemical and the gas contaminant. In conventional cleaning apparatuses other than Patent Document 1, the gas-liquid contact ratio is mostly 80% or less, and usually 60% or less, and the selection of cleaning chemicals is often not sufficiently studied, and cleaning is performed. The rate is often 50% or less. In the cleaning system of the present invention, if the selection of the cleaning chemical solution is appropriate for the reason described above, the cleaning rate: 100
% Can be obtained.
[0040]
  In order to impregnate or supply the cleaning chemical solution to the layer 2 containing the gas cleaning filler and to wet it, the cleaning device 1 has a cleaning chemical solution supply means 4 whenever the cleaning device 1 is in operation. As the cleaning chemical solution supply means 4, a method of spraying or spraying, or a method described in Patent Document 1, for example, immersing the fiber or its convergent material in a tank (cleaning chemical solution storage tank 7) storing the cleaning chemical solution, A method of transferring a cleaning chemical solution using the capillary phenomenon of the convergent and impregnating a layer containing a gas cleaning filler is preferable for a small-sized apparatus for home use or the like. In FIG. 1, the example of the method of spraying as the supply means 4 was shown. In addition, in the supply means 4 by dispersion | distribution, it is not necessary to prescribe | regulate the particle size of a dispersion | distribution mist. Particle size is 100
There is no problem even with a large mist of ˜150 μm. Needless to say, the supply means 4 is not limited to this, and may be, for example, a rotary sprayer (sprinkler). The supply means 4 is supplied with the cleaning chemical liquid from the cleaning chemical liquid storage tank 7 via the liquid flow pump 4a. As the cleaning chemical solution, a chemical solution that has been used once can be used. In the present invention, the layer 2 containing the gas cleaning filler is not immersed in the cleaning chemical solution, is separated from the cleaning chemical solution tank 6 storing the cleaning chemical solution, and is higher than the liquid level of the cleaning chemical solution tank 6. It is necessary to provide in position.
[0041]
  Next, the cleaning chemical used in the present invention will be described.
(2) Cleaning chemical
(2-1) Cleaning chemical solution impregnated and supplied to the layer containing the gas cleaning filler
  The cleaning chemical liquid impregnated and supplied in the layer containing the gas cleaning filler in the present invention is a water-soluble amphiphilic organic compound having a boiling point of 150 ° C. or higher at 1 atm (hereinafter also referred to as “amphiphilic solvent”). An aqueous solution containing The aqueous solution may not be completely transparent but cloudy. In addition, this aqueous solution contains a conventionally known chemical agent that makes it easy to remove contaminants by physical / chemical alteration using chemical reactions such as neutralization, metathesis, addition, oxidation and reduction. You can also
[0042]
  Water-soluble “Amphipathic Solvent” has the property of freely dissolving in both water and hydrophobic organic substances, improving the contact rate between cleaning chemicals and hydrophobic gaseous pollutants such as oil smoke and water-insoluble organic solvents In particular, when sprayed, it is possible to delay the drying of the cleaning chemical and increase the gas-liquid contact rate. The present inventors presume that the cleaning rate of the contaminated gas is improved by such two actions.
[0043]
  If the boiling point (under 1 atm) of the “Amphiphilic Solvent” is less than 150 ° C., it will evaporate from the mist when sprayed at room temperature, especially at high temperatures, and it will dry too quickly, reducing the gas-liquid contact rate and cleaning. The rate decreases, and an individual odor of “amphiphilic solvent” is also generated. For this reason, in the present invention, the “amphiphilic solvent” contained in the cleaning chemical solution has a boiling point of 150.
A water-soluble “amphiphilic solvent” at ℃ or higher was used.
[0044]
  By including such an “amphiphilic solvent”, there is a potential for chemical reactivity and physicochemical conjugation, but there is no reaction because it cannot be contacted with cleaning chemicals. In addition, contaminants such as aldehydes and mercaptans having a large number of carbon atoms are captured and easily reacted, and the cleaning rate of polluted gases is improved.
  The content of the “amphiphilic solvent” in the cleaning chemical solution is about 0.1 ppm or more by mass% with respect to the total amount of the cleaning chemical solution. If it is less than about 0.1 ppm, the above effects cannot be expected. Moreover, when it contains exceeding 30%, there exists a problem that the load to an environment increases, About 30% or less, Preferably it is about 10% or less. In addition, Preferably, it is about 100 ppm or less. In addition, when the cleaning chemical solution is circulated and used, about 5 to 10% is often an appropriate amount.
[0045]
  Examples of the “amphiphilic solvent” that satisfies the above-described conditions include ethylene glycol dimethyl ether (boiling point: 162.0 ° C.), triethylene glycol dimethyl ether (boiling point: 216.0).
° C), tetraethylene glycol dimethyl ether (boiling point: 275.3 ° C) and the like, but other compounds may be used.
  In addition, in the case of a cleaning chemical used by spraying, even if a surfactant is used in place of the “amphiphilic solvent”, most of the foaming occurs during spraying, so the gas-liquid contact rate decreases, It cannot be used for the cleaning chemical solution of the present invention. However, for the purpose of separating and removing the organic solvent, a preferable result may be obtained by adding a surfactant having a low foaming property and sodium chloride as a salting-out agent.
[0046]
  In addition to the “amphiphilic solvent”, the cleaning chemical solution to be impregnated is a linear molecule that is anionic, cationic or amphoteric and has no branching, and has a molecular weight measured by the intrinsic viscosity method. Is 1.0
× 10⁷ The above polyacrylamide may contain 1 to 10 ppm by mass% based on the total amount of the cleaning chemical.
  Further, it is preferable that the cleaning chemical solution containing “amphiphilic solvent” and / or polyacrylamide further contains a bactericidal / bacteriostatic agent for bactericidal / bacteriostatic use.
  As a preparation that can be contained in the cleaning chemical solution of the present invention, a complex of iodine and polyvinylpyrrolidone, and / or 2-bromo-2-nitropropane-1,3-diol, 2-pyridinothiol-1-oxide Alkali salts, 5-chloro-2-methyl-4-thiazoline-3-one, 2-methyl-4-isothiazolin-3-one, 2-N-octyl-4-isothiazolin-3-one, polyhexamethylene
It is preferable to use at least one kind selected from alkali salts of biguanides.
[0047]
  In particular, a complex of iodine and polyvinyl pyrrolidone (commonly called popidone iodine) is a composite of polyvinyl pyrrolidone that dissolves iodine in an ethyl alcohol solution and / or an aqueous solution of iodokari and further reduces toxicity. In addition, the antibacterial spectrum is wide and the bactericidal effect is excellent even at low concentrations. In addition, by adding this drug to the cleaning chemical solution at a low concentration, the concentration can be easily controlled, and iodine is constantly dissolved.
In addition to sterilizing and bacteriostatically containing the layer containing the gas cleaning filler, it is possible to sterilize and bacterize the entire interior space of the apparatus, and to sterilize microorganisms in the exhaust.
[0048]
  If the detergent solution contains anionic polyacrylamide, a dilute aqueous solution of a complex of iodine and polyvinylpyrrolidone can be added, but if amphoteric or cationic polyacrylamide is included, iodine is a cation. The complex of iodine and polyvinylpyrrolidone cannot be used to attack the group.
If the detergent solution contains amphoteric or cationic polyacrylamide, it is soluble in water and / or “amphiphilic solvent”, is compatible with the detergent solution, has no ion exchange properties, and has a wide antibacterial spectrum. Preparations such as 2-bromo-2-nitropropane-1,3-diol are suitable. In addition, preparations other than those described above can be applied as long as they are soluble in water and / or an “amphiphilic solvent”, have good compatibility with cleaning chemicals, do not exchange ions, and have a wide antibacterial spectrum. As the bactericidal / bacteriostatic agent, it is preferable to use one or more of the above-mentioned preparations, for example, 3 to 4 types, because the antibacterial spectrum is greatly expanded.
[0049]
  A sufficient effect can be obtained when the amount of the bactericide / bacteriostatic agent added in the cleaning chemical is about 1 to 5 ppm depending on the content of polyacrylamide and / or “amphiphilic solvent”. This is because the concentration of the bactericidal / bacteriostatic agent in the solid content is 20 to 100 when the cleaning chemical solution is dried.
It is because it is concentrated to%.
(2-2) Spray cleaning chemicals
  In the present invention, the cleaning chemical used for spraying is a straight-chain molecule that has one of anionic, cationic, and amphoteric charges and has no branching, and has a molecular weight measured by the intrinsic viscosity method of 1.0.
× 10⁷ The above polyacrylamide is preferably made into an aqueous solution containing 1 to 10 ppm by mass% based on the total amount of the cleaning chemical and / or a water-soluble “amphiphilic solvent” having a boiling point of 150 ° C. or higher at 1 atm. The aqueous solution may contain a conventionally known chemical agent that removes contaminants by utilizing a chemical reaction or physical action such as neutralization, metathesis, addition, oxidation / reduction, and emulsification.
[0050]
  Among the polyacrylamides described above, amphoteric ones are water-soluble and dissolve in an aqueous solution, but when dried, they form a salt-forming bond within the molecule and between the molecules to render it water-insoluble. When water is added again after drying, the gel becomes significantly swollen. As a result, molecular and aerosol substances are trapped and conjugated regardless of their chemical properties, and once trapped air pollutants are not released even when water is added.
[0051]
  When a dilute aqueous solution of this polyacrylamide, for example, a dilute aqueous solution having a concentration of 5 ppm, is sprayed to form a fine mist in the space, the mist diameter is 1 / n.
When doubled, the total mist surface area increases n times and becomes n times the gas-liquid contact rate. Also, the smaller the mist particle size, the longer the residence time in the space, and the easier it is to capture and conjugated and remove molecular and aerosol contaminants present in the space. Large aerosol pollutants such as pollen wrap around this fine mist containing polyacrylamide and fall to the floor or the bottom of the device. This fact was confirmed by video shooting in a dark room and observation of a falling object by a scanning electron microscope.
[0052]
  In particular, by including amphoteric polyacrylamide in the cleaning solution, many offensive odor components that cannot be captured by chemicals that use ordinary chemical reactions are captured and conjugated with a strong affinity presumed to be due to Coulomb force, hydrogen bonding, etc. It is considered that the deodorizing effect is improved because vaporization is hindered.
  The polyacrylamide used in the present invention can be modified from the polyacrylamide described in Japanese Patent No. 2,775,162, Japanese Patent No. 21,323,366, and Japanese Patent No. 2,1347,078. .
[0053]
  The polyacrylamide used in the present invention is capable of measuring the molecular weight by the intrinsic viscosity method so that the cleaning chemical solution can be sprayed uniformly as a fine mist having an average particle size of 30 μm or less, the molecule is completely linear, That is, it is preferably a linear molecule. Moreover, the molecular weight of polyacrylamide is 1.0.
× 10⁷ If it is less than this, the conjugation effect is insufficient, and the deodorizing effect and dust sedimentation ability are reduced. The preferred molecular weight is 2.0 × 10⁷ That's it.
[0054]
  If such a high molecular weight polyacrylamide is contained in excess of 10 ppm, the viscosity of the cleaning chemical becomes too high, and it cannot be made into a fine mist by ordinary spraying means. On the other hand, 1ppm
If it is less than 1, the effect of polyacrylamide cannot be expected. A preferable content is 3 to 7 ppm.
  Among such high molecular weight polyacrylamides, those having an anionic charge have a usable pH range of 3 to 12 and are therefore included in the polluted gas in order to effectively exhibit the function of polyacrylamide. Check the components of the main pollutants by gas chromatography, etc., check the pH of the aqueous solution of the components, and select a polyacrylamide with a product number that falls within this range,
It is preferable to adjust the pH of the cleaning chemical solution by adding an acid, an alkali such as alkanolamine, or a buffering agent such as citrate, phosphate or sodium bicarbonate to the cleaning chemical solution.
[0055]
  Moreover, since an anionic thing changes the usable pH range of a cleaning chemical | medical solution with the content rate of acid groups, such as acrylic acid, it is preferable to select and use the product number suitable for every objective. In addition, when the charge is cationic, the usable pH range is about 3 to 10, and it can be used efficiently by adjusting the cleaning chemical solution like the anionic one. Since the usable pH range of the cationic one is determined by the content of dimethylaminomethyl group or dimethylaminoethyl group, it is preferably adjusted with an additive.
[0056]
  In addition, when the charge is amphoteric, an aqueous solution containing several percent or less of the above-described high molecular weight anionic polyacrylamide is converted into methylol, and then dimerized.HLuamine, DiPhenylAmine, diisoTheIt can be produced by reacting propylamine or the like and introducing a dialkylaminomethyl group. JimeHIn the case where each molecule contains a ruaminomethyl group and a carboxyl group in an amount of about 10 to 20 mol%, equimolar,
Intramolecular and intermolecular attractive forces are dramatically increased. In addition, the usable pH range of these amphoteric ones is in the range of about 3 to 12. Depending on the main pollutants contained in the polluting gas, the pH is adjusted by adding acid, alkali, buffering agent, etc. to the cleaning chemical. It is effective to adjust.
[0057]
  In addition, the cleaning chemical solution to be sprayed alone or in addition to the polyacrylamide described above has a boiling point of 150 at one atmospheric pressure as described in the section (2-1).
It is preferable to contain about 0.1 to 100 ppm of a water-soluble “amphiphilic solvent” at a temperature equal to or higher than 0 ° C. with respect to the total amount of the cleaning chemical. By containing an “amphiphilic solvent” that is freely soluble in both water and hydrophobic organic substances in the cleaning chemical solution, the spray mist drying is delayed, and the contact rate between the cleaning chemical solution and the hydrophobic gaseous pollutant is improved. It is considered that the cleaning effect is improved.
[0058]
  When the content of the “amphiphilic solvent” is less than 0.1 ppm, the above-described effect is small. When the content exceeds 100 ppm, the coagulation property of the amphoteric polyacrylamide is inhibited, so that the conjugation effect is deteriorated. .
In addition, since all the cleaning chemicals described above are aqueous solutions that are susceptible to degradation by microorganisms, it is desirable to contain a predetermined amount of a low-toxic preservative.
[0059]
  The cleaning chemical used in the cleaning system of the present invention is a dilute aqueous solution containing a small amount of polyacrylamide and / or an “amphiphilic solvent”, and BOD and COD are so low that they can be ignored. Very low. For this reason, in many cases, it can be discharged into the septic tank or the environment after use.
In addition, the preparation described in the item (2-1) should be added to the cleaning chemical solution to be sprayed for sterilization and bacteriostasis as well as the cleaning chemical solution impregnated or supplied to the layer containing the gas cleaning filler. Can do.
(3) Main embodiments of the cleaning system of the present invention
  The cleaning system of the present invention is used in a semi-enclosed space such as a building, a subway car, a station, or a room filled with fire smoke, oil smoke, suffocating gas, or intentionally sprayed lethality. It can also be applied to the purification of air (gas) containing pollutants such as harmful gases such as gas, pathogenic microorganisms and viruses, and harmful aerosols.
[0060]
  Using the cleaning system of the present invention, these polluted gases contain a small amount of polyacrylamide and / or “amphiphilic solvent” which is a cleaning chemical solution in a semi-enclosed space such as a building, a subway car, or a station premises. When a dilute aqueous solution is sprayed, these aerosols, which are pollutants contained in the polluted gas, rapidly settle on the floor and the concentration of harmful pollutants decreases rapidly. In particular, when the “amphiphilic solvent” is included in the aqueous solution, the cleaning rate is improved by about 10 to 20% as compared with the case where it is not included. This difference becomes extremely important when replaced by the success rate of lifesaving. After that, if these polluted gases are further passed through a layer containing a gas cleaning filler impregnated with a cleaning chemical solution made of paper grains in the cleaning apparatus of the cleaning system of the present invention, a high degree of cleaning of the contaminated gases can be expected. .
[0061]
  For example, when the contaminated gas is a gas containing a water-insoluble organic compound gas having a specific gravity of 1 or less, as illustrated in FIG. 1, the above-described spray of cleaning chemical (mist having an average particle size of 30 μm or less) 3a is applied. The spray mist 3a, which is carried out in the upper part of the layer 2 containing the gas cleaning filler and traps the contaminants in the layer 2 containing the gas cleaning filler, is converted into droplets 2a, and is downstream of the layer 2 containing the gas cleaning filler.
In the lower part, separate from the layer containing the gas cleaning filler, and drop the liquid level to the liquid level of the cleaning chemical liquid tank 6 installed so as to be lower than the layer containing the gas cleaning filler. Is preferred. The droplet 2a that has fallen to the liquid surface causes the water-insoluble organic compound 7a, which is a contaminant, to float on the liquid surface of the cleaning chemical tank 6. The water-insoluble organic compound is recovered from the drain port installed at the liquid level, and the pipe 6a1
Can be separated by utilizing the difference in specific gravity on the liquid surface of the cleaning chemical solution storage tank 7 or the water tank or the contaminant treatment tank (not shown) provided outside the cleaning apparatus 1. This water-insoluble organic compound 7a is connected to the pipe 7b1.
And can be recovered through the valve 7c1. On the other hand, the gas that has passed through the layer 2 containing the gas cleaning filler is discharged from the exhaust port 9 as it is to the outside of the system (apparatus), or further, the layer 21 containing the gas cleaning filler impregnated or supplied with the cleaning chemical is used. After passing, it is preferable to discharge the gas from the exhaust port 9a to the outside of the system.
[0062]
  If the contaminated gas (air) is contaminated with extremely harmful gases or aerosols, use the average particle size of the cleaning solution containing polyacrylamide, alkaline or acidic buffer solution or insecticide according to the purpose. 30 μm
After spraying as the following mist, in addition to the “amphiphilic solvent”, a pollutant such as harmful gas and aerosol is also impregnated or supplied with cleaning chemicals containing decomposing agents and insecticides. Drop those mists into the containing layer and pollute the gas
(Air) is passed through the layer containing the gas cleaning filler and further passed through the layer containing the gas cleaning filler moistened with the above-described cleaning chemical solution, and then cleaned to a safe level. By discharging outside the equipment, the risk of secondary disasters can be significantly reduced.
[0063]
  When the pollutant gas is a gas containing a water-insoluble pollutant heated to a temperature equal to or higher than the freezing point, the pollutant gas is replaced with polyacrylamide and / or “amphiphilic solvent” which is the cleaning chemical solution of the present invention. By passing the aqueous solution containing it through the layer 2 containing the gas cleaning filler impregnated or supplied, it can be cooled and formed into droplets on the layer 2 containing the gas cleaning filler. It is preferable to drop it on the liquid surface of the cleaning chemical tank 6 separated from the containing layer 2. Piping 6a1
It is preferable to collect in the cleaning chemical solution storage tank 7 or the water tank provided continuously by the above, or to collect it further through the pipe 7b1 and the valve 7c1 and to process it in a contaminant processing tank (not shown) provided outside the cleaning apparatus 1.
[0064]
  The cleaning system of the present invention having the configuration shown in FIG. 1 can be applied to, for example, a flue gas treatment of petroleum-based forging oil in a metal forging factory.
  Smoke is introduced into the intake port 1a, and the spray means 3 is used to spray a cleaning chemical solution containing polyacrylamide, and the mist 3a has an average particle size of 30 μm or less, preferably 20 μm or less, more preferably 10 μm or less. Captures and cools hot oily smoke generated by thermal decomposition of The mist that has captured the oily smoke efficiently falls into droplets into the layer 2 containing the gas cleaning filler. In addition to the “amphiphilic solvent”, a cleaning chemical solution that is an aqueous solution containing an alkaline oxidizing agent is supplied to the layer containing the gas cleaning filler by the supply means 4, and the odors of aldehydes contained in the contaminated gas are reduced. Deodorizes and tarizes oil smoke. The mist 2a containing the contaminants dropletized in the layer 2 containing the gas cleaning filler has a liquid level below the layer containing the gas cleaning filler and below the layer containing the gas cleaning filler. It falls on the liquid level of the provided cleaning chemical tank 6 and floats. The floated contaminants are collected from the drain port provided at the liquid level of the cleaning chemical liquid tank 6, transferred to the cleaning chemical liquid storage tank 7 through the piping / valve, and separated using the specific gravity difference, and the pipe 7b1
Recovered from.
[0065]
  If the cleaning system of this invention shown in FIG. 1 is utilized, the oily smoke which could not be removed by the conventional apparatus can be easily removed, and the deodorization rate of odors of aldehydes can be increased. The cleaning chemical supplied to the layer containing the gas cleaning filler can be circulated and used until it is no longer effective.
  Moreover, if the washing | cleaning system of this invention shown in FIG. 1 is utilized, the removal of the mist of cooking oil contained in the exhaust_gas | exhaustion of the fried food factory for lunch, or the exhaust_gas | exhaustion of a kitchen, and the removal of cooking odor will be attained similarly. In addition, 1 polyacrylamide is added to the cleaning chemical.
By containing ˜2 ppm, it is effective for deodorizing complex mixed odors at low concentrations.
[0066]
  In addition, when the cleaning system of the present invention is used, when the waste polystyrene foam material is heated and melted at 200 ° C. or higher in the cooking oil waste oil, the styrene monomer generated by depolymerization of the polystyrene can be deodorized and removed. It becomes possible.
  In addition, the cleaning system of the present invention is a hydrogen sulfide in methane gas (biogas) generated by microbial decomposition of biomass such as livestock manure, wood waste, agricultural waste, garbage, etc., and an alkyl with a strong odor. It can be applied to the removal of contaminants such as mercabtan, methyl sulfide, suspected harmful bacteria and their spores.
[0067]
  Biogas is usually considered to be used as a fuel gas in volume%, containing about 60% methane, about 40% carbon dioxide, and 0.15 to 0.4% hydrogen sulfide. However, when this biogas is burned, hydrogen sulfide is converted into sulfurous acid gas of the same volume and released into the atmosphere, and the combustion equipment is damaged. This gas also releases bacteria and their spores. For this reason, removal of hydrogen sulfide and bacteria from biogas is important.
[0068]
  In the cleaning system of the present invention, when the contaminated gas is a gas containing hydrogen sulfide such as biogas, the cleaning device as shown in FIG. 1 is used to impregnate the layer containing the gas cleaning filler. Or, as a cleaning chemical that is supplied and moisturized and / or as a cleaning chemical that is sprayed onto a contaminated gas, an “amphiphilic solvent” and a reaction that liberates hydrogen sulfide as sulfur are usually used to increase the reaction rate and reaction rate. One or more selected from a trialkanolamine having a boiling point of 250 ° C. or higher, an alkali metal hydroxide, or an alkali metal carbonate, or further selected from an alkali salt of sulfurous acid And / or an alkaline aqueous solution containing one selected from alkali salts of bisulfite. Examples of trialkanolamine having a boiling point of 250 ° C. or higher at normal pressure include low volatility and non-mutagenic properties such as triethanolamine, tri (iso) propanolamine, and triisopropanolamine.
[0069]
  The method that does not use an alkaline substance has long been known as Buckenloader's solution, and is a reaction that reacts hydrogen sulfide with sulfurous acid gas in water for a long time to produce hydrosol-like sulfur.
SO₂ + 2H₂S = 2H₂O + 3S (1)
(For example, Risazo Chiya, Inorganic Chemistry, Volume 2, p851, p896-897, p907, published in May 1947, Sangyo Tosho Co., Ltd.).
[0070]
  When hydrogen sulfide and sulfurous acid gas are reacted in the presence of an alkali compound, sulfur is liberated through formation of precursor trithionate and tetrathionate. The method of the present invention using an alkaline aqueous solution is alkaline because hydrogen sulfide has a lower solubility in water than that of sulfurous acid gas (the solubility of hydrogen sulfide in water at 15 ° C. is about 6% of the solubility of sulfurous acid gas). Hydrogen sulfide is neutralized with a compound to increase the sulfur ion concentration, thereby increasing the reaction rate and yield. This method is effective when a low concentration of hydrogen sulfide is included.
[0071]
  Trialkanolamines, alkali metal hydroxides, and alkali metal carbonates react with carbon dioxide at the start of washing to form bicarbonate, which lowers the pH of the solution, but simultaneously reacts with hydrogen sulfide (neutralization) ) To form a sulfide salt and dissolve in the cleaning chemical. Moreover, the alkali salt of sulfurous acid and the alkali salt of bisulfite liberate sulfur by the reactions of the following formulas (2) to (4).
[0072]
  In the case of a pollutant gas with a high hydrogen sulfide concentration, a sulfur dioxide gas equivalent to or slightly lower than the reaction equivalent of hydrogen sulfide is blown into an aqueous solution containing an “amphiphilic solvent” or the above-described cleaning chemical. The method is effective. When the sulfurous acid gas is blown into the cleaning chemical solution, for example, it is preferable to blow it into the cleaning chemical solution storage tank 7 of FIG. In addition, when the sedimentation of sulfur is slow due to the generation of the precursor, an oxidation separation tank for sulfur that blows air may be installed in addition to the cleaning chemical liquid storage tank 7. This facilitates long-time cleaning of, for example, biogas containing a high concentration of hydrogen sulfide.
[0073]
  For example, when sulfite gas is blown into a cleaning chemical solution containing alkali metal carbonate in the cleaning chemical solution, the sulfurous acid gas is expressed by the following formula (2):
Na₂CO₃+ SO₂ = Na₂SO₃+ CO₂
(2)
The hydrogen sulfide is converted into the following formula (3)
Na₂SO₃+ 2H₂S + CO₂ = Na₂CO₃+ 2H₂O
+ 3S (3)
It reacts like this. That is, it is considered that sulfur can be liberated and precipitated without reacting with the chemical in the cleaning chemical solution by reacting as in the formula (1). In the case of alkali metal hydroxide, sulfurous acid gas reacts as shown in the following equation (4).
[0074]
2NaOH + SO₂ = Na₂SO₃+ H₂O ...... (4)
  This product sodium sulfite liberates sulfur by the reaction of formula (3). Alkalis in other cleaning chemicals also act as catalysts, and it is considered that sulfur can be liberated and precipitated without consuming chemicals. This method theoretically does not consume the drug in the cleaning solution.
[0075]
  In order to blow sulfurous acid gas into the cleaning chemical solution, as shown in FIG. 1, hydrogen sulfide is supplied from a sulfurous acid gas supply port 8a through a pipe 8b connected to a sulfurous acid gas supply source (cylinder or the like: not shown). What is necessary is just to mix the sulfur dioxide gas of the reaction equivalent with hydrogen sulfide or less into the contaminated gas. The sulfurous acid gas supply source may burn sulfur at the place of consumption instead of the cylinder.
[0076]
  The colloidal sulfur that is liberated and settled in the cleaning chemical solution can be recovered and reused. For the recovery of sulfur, for example, it is preferable to add saline as a coagulant for sulfur in the cleaning chemical solution storage tank 7 of the cleaning apparatus 1 shown in FIG. Thereby, sulfur precipitates at the tank bottom. The precipitate is recovered and the supernatant can be circulated and reused.
  This method theoretically does not consume the drug in the cleaning solution. However, a biogas containing unreacted sulfurous acid gas and hydrogen sulfide is stored in the same alkaline cleaning chemical solution in order to completely remove sulfurous acid gas and hydrogen sulfide in preparation for a situation where the gas is ejected from the device due to the failure of the device, etc. It is preferable to provide another cleaning chemical storage tank.
[0077]
  In addition, sarin (C₄H₁₀FO₂P), Taboon (C₅H₁₁N₂
O₂P), mustard gas (C₄H₈C_l2Detoxification of contaminated gas containing lethal toxic gas such as S) can be easily performed by using the cleaning system of the present invention. “Amphipathic solvent” is added to anionic polyacrylamide or amphoteric polyacrylamide, and an alkaline cleaning agent is sprayed onto a fine mist of about 10 μm to obtain sarin (C₄H₁₀FO₂P
), Taboon (C₅H₁₁N₂ O₂P), mustard gas (C₄H₈C_l2If sprayed onto a contaminated gas containing a deadly toxic gas such as S), the toxic gas can be easily captured and further detoxified by passing it through a layer containing a gas cleaning filler impregnated or supplied with a strong alkaline solution. It is considered that there is a great possibility that leakage of harmful gases to the outside can be prevented. In this case, it may be desirable to perform the spraying outside the apparatus.
[0078]
  Also, in a cleaning system that uses an aqueous solution as a cleaning chemical, the cleaning device tends to be a growth medium for microorganisms, so that bacteria, fungi, algae, etc. are easily discharged into the exhaust gas after the cleaning process. Therefore, when the cleaning system of the present invention is applied, for example, when the cleaning system is continuously operated for a long time in a garbage processing facility, a fish meal processing facility, a chemical factory, a nursing facility, a hospital, etc., the apparatus and the cleaning chemical solution Measures against sterilization and bacteriostasis are required, and it is necessary to prevent microbial disasters.
[0079]
  For example, bacteria, fungi and spores that have been entrained in an air stream from a source of contamination and entered the cleaning device or have further proliferated are entrained and suspended in the air flow, but are aerosolized and molecular contaminants in the cleaning device. In contrast, it is hardly in contact with cleaning chemicals and gas cleaning fillers. Gas molecules have a very high moving speed at 15 ° C., for example, 447.2 m / s for hydrogen sulfide and 272.0 m / s for toluene. These are other gases and device surfaces until they are trapped in the cleaning chemical. And repeated collisions,
It jumps in all directions and easily collides with and is absorbed by cleaning chemicals and gas cleaning fillers, but spherical bacteria with a diameter of 1 μm are aerosols that only flow about 0.035 cm / s as they flow into the air stream. .
[0080]
  Therefore, although such aerosol-like pollutants are difficult to remove by conventional chemical cleaning methods, the cleaning system of the present invention uses an aqueous solution containing polyacrylamide and / or an “amphiphilic solvent” as a cleaning chemical. Then, such aerosol-like pollutants can be removed. Therefore, if sterilization / bacteriostatic agent is added to the cleaning chemical solution to be impregnated / supplied into the layer containing the cleaning chemical solution to be sprayed and / or the gas cleaning filler for sterilization / bacteriostatic, it will float in the airflow Bacteria,
Fungi and spores and / or bacteria, fungi and spores adhering to the layer containing the gas cleaning filler can be captured and dispersed in the cleaning chemical solution, and these can be easily sterilized and bacteriostatic. As the bactericidal / bacteriostatic agent to be added to the cleaning chemical solution, as described in the section (2-1), it is preferable to use a complex of iodine and polyvinylpyrrolidone or the like.
[0081]
  In the cleaning system of the present invention, air that cannot be completely removed by the methods described in Japanese Patent No. 2,775,162, Japanese Patent No. 21,323,366, and Japanese Patent No. 2,1347,078. Very low olfactory threshold, present in water-insoluble or sparingly soluble, uncharged, chemically neutral or low-reactive organic compounds such as medium pollutants such as middle and lower fatty acids, alcohols and aldehydes It can completely remove odorous and strong substances.
[0082]
  Further, in the cleaning system of the present invention, in the olfactory measurement method based on human olfaction of the Ministry of the Environment, a gas containing a pollutant such as a bad odor component that is strong enough that the odor concentration may exceed 100,000.
(Air), for example, exhaust from microbial decomposition equipment such as garbage can be almost completely deodorized. The gas discharged from microbial decomposing equipment such as garbage cannot be deodorized by a chemical reaction because of its complicated composition containing a large amount of bacteria, its spores, and harmful gases, and extremely many pollutant components. In the cleaning system of the present invention, some chemical reaction also contributes, but it is considered that it is almost eliminated by the physicochemical conjugation action of the cleaning chemical used in the present invention.
[0083]
【Example】
Example 1
  Paper pulp made from delignified fiber is used as a raw material, and the raw material is placed in a container that rotates at high speed, and the fibers are entangled. Paper grain. The obtained paper grain was passed through a wire mesh sieve, and the average length: 7.0
Paper grains in the range of ± 0.2 mm, width: 5.5 ± 0.2 mm, and thickness: 4.0 ± 0.2 mm were collected. These paper grains had a humidity of 60% and an apparent specific gravity of 195 g / L. This paper grain was used as a gas cleaning filler material.
[0084]
  The filler material (paper grain) 5L (975 g) is subjected to A treatment, B treatment, or C treatment, and a gas cleaning filler (No. A, No. B, No. C) (invention example) and did. Moreover, after performing D process as a pre-processing, A process is performed and the gas cleaning filler (No.
DA) (example of the present invention).
(1) No. A (Invention Example)
  The gas cleaning filler (No. A) was subjected to the following A treatment on the filler material to obtain a gas cleaning filler.
[0085]
A treatment:
  60 g of 50% aqueous solution of dimethyl roll dihydroxyethylene urea per kg of the treatment liquid, complete saponification, polyvinyl alcohol (PVA with a polymerization degree of 1800)
) 7% aqueous solution of 300%, and an equivalent amount of nitric acid to make it water-soluble.⁴ 10 g of 1% aqueous solution of chitosan and 3 g of ammonium chloride
Then, 300 g of methanol and 327 g of water were dissolved and mixed to obtain a 10 L aqueous solution (treatment liquid). In this treatment liquid, a filler material (paper grain) placed in a mesh bag made of nylon filament fiber is immersed for 2 minutes and impregnated with the treatment liquid, and then pulled up and centrifuged (approximately 2000 rpm).
In this case, the liquid material is removed from the bag for 7 minutes so that the mass ratio of the paper particles to the treatment liquid is about 1: 1, and then the box is removed from the bag with a stainless steel net on the bottom. Put it so that it doesn't overlap, 130
After drying and curing for 45 minutes in a constant temperature / hot air circulating drier kept at ℃, it was taken out.
(2) No. B (Example of the present invention)
  The gas cleaning filler (No. B) was subjected to the following B treatment on the filler material to obtain a gas cleaning filler.
[0086]
B treatment:
  After immersing the filler material (paper grain) in a mesh bag made of nylon filament fiber for 2 minutes in an aqueous solution (treatment solution) of 50g methanesulfonic acid and 9950g water mixed / dissolved per 10kg treatment solution Pull up the centrifuge (approximately 2000 revolutions /
Then, the mixture was drained for 7 minutes so that the mass ratio of the paper grains to the treatment liquid was about 1: 1, dried until the water content became 8%, and then a wire mesh was put on the bottom in the sealed chamber. The box was placed horizontally, and the paper grains were placed in it so as not to stack. Next, place the paper particles that have been treated in the sealed chamber, put 100 g of paraformaldehyde and water into a 1 L Erlenmeyer flask outside the sealed chamber, and gently heat the generated formaldehyde vapor into the sealed chamber. Then, after reacting the formaldehyde vapor with the paper grain, it was treated with water vapor to remove unreacted formaldehyde.
(3) No. C (Example of the present invention)
  The gas cleaning filler (No. C) was subjected to the following C treatment on the filler material to obtain a gas cleaning filler.
[0087]
C treatment:
  50g of methane sulfonic acid per 10kg of treatment liquid, 3000g of 7% aqueous solution of polyvinyl alcohol having a degree of polymerization of 1800, and a molecular weight of 2.0 made water-soluble by adding an equal amount of nitric acid
A 104% 1% aqueous solution of chitosan, 2000 g of methanol, 4850 g of water, and a mixed / dissolved aqueous solution were used as the treatment liquid. After being immersed, drained, and dried in this treatment liquid in the same manner as the B treatment, Finished by reacting gaseous formaldehyde.
(4) No. DA (Example of the present invention)
  The gas cleaning filler (No. DA) was subjected to the following D treatment as a pretreatment on the filler material (paper grain), and then subjected to the A treatment to obtain a gas cleaning filler.
[0088]
D processing:
  An aqueous solution containing 90 g of 85% phosphoric acid, 150 g of urea, 200 g of methanol, 560 g of water, and mixed and dissolved is used as a pretreatment solution per 1 kg of the treatment solution, and this filament is made of nylon filament fiber mesh. The filler material (paper grain) placed in the bag is immersed for 2 minutes and impregnated with the treatment liquid, and then pulled up and centrifuged (approximately 2000 rpm).
And after 7 minutes so that the mass ratio of the paper grains to the treatment liquid is about 1: 1, the filler material is taken out of the bag and kept in a constant temperature / hot air circulating drier maintained at 130 ° C. for 45 minutes. Dry, then 150 in the same dryer
A heat treatment at 30 ° C. for 30 minutes was performed.
(5) No. E (comparative example)
  Further, the above-described filler material (paper grain) 5L is subjected to a treatment outside the scope of the present invention, which is the same as the A treatment except that PVA and chitosan are not included, and a gas cleaning filler (No.
E) (comparative example).
[0089]
  The obtained gas cleaning filler, No. A, No. C, No. DA and No. For E, each was charged into the layer 2 containing the gas cleaning filler in the cleaning apparatus of FIG. 1, and the increase in pressure loss when actually used for 30 days was comparatively tested. The layer 2 containing the gas cleaning filler was formed by laminating the gas cleaning filler with a thickness of 30 cm. In this test, spray cleaning is not performed, air is passed instead of the contaminated gas, and the layer 2 containing the gas cleaning filler supplied and impregnated with the cleaning chemical liquid in the cleaning chemical storage tank 7 is passed through the exhaust port 9. Exhausted.
[0090]
  The cleaning chemical was supplied by a liquid flow pump 4a operated by an electromagnetic valve linked to a liquid level meter so that the liquid amount was constant during operation. The cleaning chemicals used were the following (A) and (B).
(A) Strongly acidic solution: a solution obtained by diluting a solution obtained by adding 65 ml of 2 mol / ml hydrochloric acid to 250 ml of 2 mol / L ammonium chloride, and having a pH of 2.0
(B) Strongly basic solution: a solution obtained by diluting a solution obtained by adding 530 ml of 2 mol / L sodium hydroxide to 250 ml of 2 mol ml of potassium chloride solution to 1 L with water, and having a pH of 12.9 The pressure loss is measured after 1 day and 30 days from the start of operation by connecting a small valve attached to the portion 1c in FIG. 1 and a small valve attached to the exhaust port 9 to a water pressure gauge via a silicone tube. It was measured. One day after the start of operation was taken as the initial value. The unit of pressure loss was the height of the water column (mmAq).
[0091]
  The obtained results are shown in Table 1.
[0092]
[Table 1]

[0093]
  As a result of this test, the inventive example (No. A, No. C, No. DA) had an increase in pressure loss of about 15%, but the comparative example (No. E) was crushed and deformed by its own weight. The pressure loss increased more than twice.
  Next, 5 g of each of the obtained gas cleaning fillers was put into 100 ml of a 0.01% aqueous solution of trimethylamine having an inherent malodor, and the odor of the aqueous solution was tested by human odor. As a result, the gas cleaning filler (No.
Only when DA) was added, the malodor of trimethylamine was eliminated.
(Example 2)
  The airflow (air) discharged from the food waste decomposing apparatus having a processing capacity of 30 kg / day was cleaned using the cleaning apparatus outlined in FIG.
[0094]
  This food waste decomposition apparatus has a horizontally long and cylindrical decomposition chamber, and has a dust inlet that is airtight and openable on the top surface. In the decomposition chamber, sawdust that holds bacteria and is used for a long time is placed. After the food waste is introduced from the garbage inlet, the fresh air is sent to the decomposition chamber with a blower, and the contents (food waste) are cut back by the rotating blades attached vertically to the horizontal shaft. Further, the rotation and stop of the rotor blades are repeated every 15 minutes while adjusting the humidity and temperature of the decomposition chamber within a certain range by the control device. From the exhaust hole of this food waste decomposition apparatus, a high-humidity air stream having a strong foul odor and containing carbon dioxide gas, harmful gas, microorganisms, spores and the like is discharged.
[0095]
  The used cleaning apparatus 1 is a vertically long rectangular parallelepiped (800 × 800 × height 1500 mm), has an intake port 1a for introducing a processing gas on the upper side surface, and an exhaust port for discharging the cleaned gas on the lower side surface. 9 Separated from the cleaning chemical solution tank 6, a layer 2 containing a gas cleaning filler is provided on the upper surface of the cleaning chemical solution tank 6. Further, spray means 3 is provided below the intake port and above the layer 2 containing the gas cleaning filler. The spray means 3 (spray gun) can spray a mist of a cleaning chemical solution having an average particle size of 20 μm as measured by a laser light scattering particle size distribution measurement method at a position 15 cm from the injection port in parallel with the contaminated gas to be cleaned. It is said. The layer 2 containing the gas cleaning filler was formed by laminating the gas cleaning filler with a thickness of 30 cm. The gas cleaning filler used was No. 1 used in Example 1 in which the filler material (paper grain) was subjected to A treatment.
A.
[0096]
  In addition, the cleaning chemical liquid sucked by the liquid flow pump 4a from the cleaning chemical liquid storage tank 7 is sprayed and supplied to the layer 2 containing the gas cleaning filler by the supply means 4 (here, using a rotary sprinkler), The layer 2 containing the cleaning filler is wet with a cleaning chemical.
  The cleaning chemical liquid to be impregnated / supplied into the layer containing the cleaning chemical liquid to be sprayed and the gas cleaning filler is a straight-chain molecule and has a molecular weight of 1.8 × 10 in the intrinsic viscosity method.⁷
5 ppm of amphoteric polyacrylamide in which 15 mol% of acrylic acid and 15 mol% of dimethylaminomethyl groups are bonded, and 2 ppm of triethylene glycol dimethyl ether which is an “amphiphilic solvent”
Sodium bicarbonate as a buffer, 0.1 ppm, bactericidal and bacteriostatic agent, 2-N-octyl-4-isothiazolin-3-one, and hexamethylene biguanide sodium salt, 5 ppm each
It was set as the aqueous solution (cleaning chemical | medical solution a) containing. For comparison, an experiment was also conducted on a cleaning chemical solution (cleaning chemical solution b) obtained by removing triethylene glycol dimethyl ether which is an “amphiphilic solvent” from the cleaning chemical solution a.
[0097]
  At the same time, 15 kg of raw vegetable chopping chips, 5 kg of expired cooked rice, and 10 kg of raw tuna were introduced 3 times every other day (6 days) from the waste input of the food waste decomposition apparatus described above. . And the airflow (air) discharged | emitted from the exhaust hole of a food waste decomposition device was extract | collected as a sample, and the odor density | concentration was measured. The samples were collected 5 hours and 23 hours after the introduction of the waste, and were repeated every 6 times (total 3 times). In addition, since the odor concentration and the fungal discharge concentration increase when the turnover is performed, the airflow to be discharged was collected while the contents of the decomposition chamber were turned over by the rotor blades. It has been confirmed that the odor concentration becomes the highest after 5 hours from the introduction of the waste and becomes the lowest after 23 hours. The highest concentration is obtained after 5 hours from the introduction of the waste, and the lowest is obtained after 23 hours. It will represent the concentration. The maximum value and the minimum concentration were averaged three times, and the average value was used as the odor concentration.
[0098]
  The collected sample was supplied by a pump to the intake port 1a of the cleaning device shown in FIG. In the cleaning apparatus 1, the above-described cleaning chemical liquid is sprayed from the spray means 3 so as to become a mist having an average particle diameter of 20 μm in parallel with the inhaled contaminated gas, and the above-described cleaning chemical liquid is supplied and impregnated. 2m of layer 2 containing the gas cleaning filler³
The pollutant gas was washed at a rate of / min and discharged from the exhaust port 9. The odor concentration was measured using the discharged airflow as a sample.
[0099]
  The measurement of the odor concentration was carried out by continuously diluting fresh air into the measurement target gas (sample), and determining the dilution factor at the time when six persons with normal olfaction were unable to smell each other. The average value of the measurement values (dilution ratio) of four people excluding the highest value and the lowest value among the six people was defined as the odor concentration.
  The cleaning rate of the pollutant gas by the cleaning system of the present invention was determined from the odor concentration of the airflow discharged from the food waste decomposition device and the odor concentration of the gas after being cleaned by the cleaning device. The cleaning rate (%) is {(odor concentration of the airflow discharged from the food waste decomposition device) − (odor concentration of the gas after being cleaned by the cleaning device)} / (discharged from the food waste decomposition device) Odor concentration of airflow) x 100
It is a value defined by (%).
[0100]
  The obtained results are shown in Table 2.
[0101]
[Table 2]

[0102]
  In the cleaning system (invention example) using the gas cleaning filler and cleaning chemical solution within the scope of the present invention, the cleaning rate is almost 100%, and the contaminants can be almost completely removed. When the cleaning chemical solution is used, the cleaning rate is low and the contaminants cannot be completely removed. From this result, the usefulness of the “amphiphilic solvent” was confirmed.
(Example 3)
  A room of a reinforced concrete building just before dismantling (space capacity: 120 m³ ) To detoxify (remove) hydrogen sulfide contained in the air. In order to make the room completely airtight, the door gap and opening were filled with putty, and the window glass gap was sealed with adhesive tape.
[0103]
  At the center of such a room, first, dilute sulfuric acid is added to iron sulfide placed in an Erlenmeyer flask to generate hydrogen sulfide (allowable concentration: 10 ppm, lethal concentration: 1000 ppm). The concentration was made uniform. Next, when a person wearing a gas mask measured the indoor hydrogen sulfide gas concentration with a Kitagawa gas detector tube, it was 60 ppm.
Met. After one hour, the hydrogen sulfide gas concentration in the room was measured in the same manner. As a result, it reacted with walls, floors, etc. or leaked outside the room, and it was 54 ppm (gas concentration reduction rate: 10% / hour). This gas concentration: 54ppm
Was the initial value.
[0104]
  Subsequently, the above-described cleaning chemical solution was sprayed throughout the room for 3 minutes at a spray amount of about 90 g / min. Spraying is performed using a movable three-fluid spraying device, and the average particle size of the spray mist of the cleaning chemical at that time is 10 μm as measured by a laser light scattering particle size distribution measurement method at a position 15 cm from the injection port. It was. The cleaning chemical solution used was the cleaning chemical solution a used in Example 2.
[0105]
  When the mask was removed 1-2 minutes after spraying, it was felt that most of the hydrogen sulfide was removed olfactoryly, but when the indoor hydrogen sulfide gas concentration was measured 2-3 minutes after spraying, it was found to be 12 ppm.
Met. The cleaning rate defined by {(initial gas concentration) − (gas concentration after spraying)} / (initial gas concentration) × 100 (%) is 78%.
  As a result of the spraying of the cleaning chemical solution, almost 100% of the hydrogen sulfide diffused in the room was trapped in the spray chemical mist of the cleaning chemical solution, but only 80% of that amount settled on the floor. The remaining 20% equivalent was detected by the detector tube in a state where the mist particle size was small, and the particle size was reduced by evaporation of water and the hydrogen sulfide was retained, but did not settle on the floor and floated in space. It is considered that the hydrogen sulfide odor was not felt because it entered the nostril in a gel state.
[0106]
  Then, as described above, the room air sprayed with the cleaning chemical solution in the room was sucked into the intake port 1a of the cleaning apparatus 1 shown in FIG. 1 to clean the room air.
The cleaning device used has a layer 2 containing a gas cleaning filler inside, and further separated from the layer 2 containing the gas cleaning filler, and below the layer 2 containing the gas cleaning filler, A cleaning chemical liquid tank 6 having a liquid level lower than that of the layer 2 containing the gas cleaning filler is provided, and a cleaning chemical liquid storage tank 7 for storing the cleaning chemical liquid is connected to the cleaning chemical liquid tank 6 through a pipe. . Further, the cleaning device is provided with a cleaning chemical solution supply means 4 composed of a rotary sprinkler, to which the cleaning chemical solution is supplied from the cleaning chemical solution storage tank 7 via the liquid flow pump 4a. The supply means 4 supplies and impregnates the cleaning chemical to the layer 2 containing the gas cleaning filler, and the layer 2 containing the gas cleaning filler retains wettability. In the cleaning device 1, the contaminated gas (room air) is cleaned through the layer 2 containing the wet gas cleaning filler, cleaned, and discharged from the exhaust port 9.
[0107]
  The layer 2 containing the gas cleaning filler is formed by horizontally applying the gas cleaning filler (No. B) (see Example 1), which has been subjected to the B treatment for imparting only water resistance to the paper grain, onto the stainless steel wire mesh. Was laminated to a thickness of 30 cm. The cleaning chemical used was 20 g of triethylene glycol dimethyl ether as an “amphiphilic solvent” per 1 kg of the chemical.
Furthermore, 80 g of sodium hydroxide, 40 g of sodium bicarbonate, 10 g of sodium persulfate as an oxidizing agent, 40 g of triethanolamine having a high affinity for hydrogen sulfide in an organic solvent
And 810 g of water were mixed and dissolved to obtain an aqueous solution (cleaning chemical c). The cleaning device used was manufactured by modifying an existing drum can (about 200 L). Pressure loss is 20mm due to simple structure
About aq, 6-8m³ It is possible to clean the contaminated gas at about 1 / min.
[0108]
  Kitakawa-type gas detector tube is used for the air discharged from the exhaust port 9 after cleaning the indoor air after the hydrogen sulfide is diffused into the room and the cleaning chemical is sprayed with the cleaning device shown in FIG. The concentration of hydrogen sulfide gas was measured in the same manner, but was not detected at all.
Example 4
  In the same airtight room as in Example 3, sulfur was burned to generate sulfurous acid gas (allowable concentration: 2 ppm, lethal concentration: 400 ppm), and the gas concentration in the room was made uniform. When the sulfur dioxide concentration in the room was measured by a measurer wearing a mask, 40 ppm
Met.
[0109]
  Next, as in Example 3, the cleaning chemical solution was sprayed throughout the room. The cleaning chemical used was the same as in Example 3 (cleaning chemical a). When the gas concentration in the room after spraying was measured with a Kitagawa type gas detector tube in the same manner as in Example 3, it was found to be 4 ppm.
Got. The cleaning rate was 90%.
  Subsequently, the room air after spraying the cleaning chemical was sucked into the cleaning device 1 shown in FIG. The gas cleaning filler and cleaning chemical used were the same as in Example 3. The sulfur dioxide concentration of the air discharged from the exhaust port 9 of the cleaning device 1 shown in FIG. 1 was measured with a Kitagawa gas detector tube, but was not detected.
(Example 5)
  An experiment was conducted on the cleaning of air currents containing paint mist and organic solvents discharged from a paint booth at a spray painting plant.
[0110]
  First, a 3x3x3m skeleton is made with steel pipes inside the spray painting factory building, and the outer surface is covered with a polyethylene film (thickness: 0.15mm), and the floor is covered. Placed a tray, and a dust removal booth with a spray nozzle of a three-flow sprayer was installed in the upper center part so that it could spray downward. The spray nozzle was a nozzle capable of generating mist having an average particle diameter of 10 μm at a position 50 cm from the spray port. The exhaust port of the dust removal booth is provided with a layer containing a gas cleaning filler that is moistened with a cleaning chemical solution for secondary dust removal, and through this layer, most of the solid content in the paint has not been removed. Al flexible pipe (diameter: 150mm) for sucking gas containing organic solvent mist
) Is joined. The layer containing the gas cleaning filler for secondary dust removal is composed of the gas cleaning filler (gas cleaning filler No. B: Example 1) subjected to the B treatment for imparting water resistance to the paper grain. ) Was used (thickness: 20 cm). Further, the cleaning chemical solution (cleaning chemical solution d shown below) is intermittently supplied to the layer containing the gas cleaning filler from the pores opened at the tip of the vinyl chloride tube fitted to the small liquid flow pump. Is done.
[0111]
  The other end of the Al flexible pipe connected to the exhaust port of the dust removal booth is connected to the intake port 1a of the cleaning device 1 shown in FIG. The cleaning device 1 is a stainless steel drum (inner diameter 580 mm).
× Height 850 mm: Internal volume 230 L) is modified, and an air inlet 1a is provided at the center of the lid. A spraying means (spray nozzle) 3 of a three-flow sprayer is installed on the upper part of the cleaning device so that it can spray downward, and a layer 2 containing a gas cleaning filler at a position 40 cm below the spray nozzle (
The thickness of the filler: 20 cm) was laminated horizontally. In addition, the layer 2 containing this gas cleaning filler used the gas cleaning filler (gas cleaning filler No. B: refer to Example 1). The layer 2 containing the gas cleaning filler is sprayed with a cleaning chemical solution (cleaning chemical solution e shown below) by a rotary sprayer, impregnated and supplied, and constantly wetted. Moreover, the spray means 3 (spray nozzle) was made into the same form as the spray nozzle installed in the dust removal booth.
[0112]
  From the spray means 3 (spray nozzle) in the cleaning apparatus, a space (about 0.1 m) with the layer 2 containing the gas cleaning filler.³ ), The cleaning chemical solution (cleaning chemical solution d shown below) is sprayed in parallel with the airflow from the intake port. The mist of the sprayed cleaning chemical solution is measured by a laser light scattering particle size distribution measurement method at a position 15 cm from the injection port, and the average particle size is 10 μm.
Met. The air stream sprayed with the cleaning chemical solution (cleaning chemical solution d) is formed into droplets in the layer containing the gas cleaning filler, and accumulates together with the cleaning chemical solution in the cleaning chemical solution tank 6 at the bottom of the cleaning device. In the cleaning apparatus shown in FIG. 1, the amount of liquid accumulated at the bottom of the cleaning apparatus is constant (liquid level: 35 cm), and if it exceeds that, a drop is placed in the cleaning chemical liquid storage tank 7 outside the apparatus through a pipe provided on the side of the cleaning apparatus. It is designed to flow in. The cleaning chemical stored in the cleaning chemical storage tank 7 is supplied to the supply means 4 (rotary watering device) by the liquid flow pump 4a and reused. The reduced amount of cleaning chemical is adjusted and replenished as needed. Further, the organic solvent for coating that has floated on the liquid surface of the cleaning chemical solution storage tank 7 is separated and collected by utilizing the difference in specific gravity.
[0113]
  The cleaning chemical solution d has a molecular weight of 2.0 × 10 6 per kg of a linear molecule and anionic.⁷ (Intrinsic Viscosity Method), 5g of triethanolamine salt of polyacrylamide in which acrylic acid is copolymerized 15% in 1kg of mass
An aqueous solution containing 0.5 g of triethylene glycol dimethyl ether as an “amphiphilic solvent”, 0.5 g of diethylene glycol dimethyl ether, and a complex of iodine as a bactericide and polyvinyl pyrrolidone in an amount of 0.001 g in terms of iodine .
[0114]
  In order to make the organic solvent in an incompletely emulsified state, the cleaning chemical solution e is 0.2 g of polyoxyethylene sorbitan monostearate having an HLB value of 15.0 per 1 kg of the mass.
Was a mixed aqueous solution.
  Using such a dust removal booth and the cleaning device 1, the amount of air blown at the dust removal booth entrance is 3 m.³ The gas discharged from the painting booth was cleaned by adjusting to 1 / min.
[0115]
  As a result, when spraying the cleaning agent in the dust removal booth, it was observed that the paint mist that had not been visible until now was settled down to the floor so that snow would suddenly fall from the clear sky.
  The gas sprayed with the cleaning chemical solution in the dust removal booth was then sprayed in the cleaning device 1, formed into droplets in a layer containing a gas cleaning filler, and exhausted from the exhaust port of the cleaning device. The odor concentration of the exhausted gas was measured by the same method as in Example 1. As a result, the odor concentration was 1100 (dilution ratio). The odor concentration of the gas exhausted from the painting booth measured by the same method is 21000.
(Dilution ratio) also shows that the cleaning system of the present invention is effective.
[0116]
  In addition, spraying of the cleaning chemical solution in the dust removal booth was also conducted in the case where the average particle size of the spray mist was set to 50 μm using a two-fluid sprayer (comparative example), but sedimentation to the floor per fixed spray amount The amount was about 15% of the inventive example.
(Example 6)
  Using the cleaning apparatus shown in FIG. 1, an experiment was conducted to remove hydrogen sulfide contained in a large amount in biogas.
[0117]
  In addition, the layer 2 containing the gas cleaning filler in the cleaning apparatus 1 is a gas cleaning filler No. 1 which has been subjected to C treatment for imparting water resistance and hardness to the paper grain as the gas cleaning filler.
C (see Example 1) was used to form two layers of this gas cleaning filler layered to a thickness of 25 cm so that the gas-liquid contact was doubled.
  The cleaning chemical solution impregnated or supplied to the layer 2 containing the gas cleaning filler was the cleaning chemical solution f shown below.
[0118]
  The cleaning chemical solution f is mixed by mass with 2% of triethylene glycol dimethyl ether which is an “amphiphilic solvent”, 10% of caustic soda and 0.01% of iodine / polyvinyl pyrrolidone complex in terms of iodine. A dissolved aqueous solution was obtained.
A certain amount of hydrogen sulfide was mixed into the air sucked by the suction blower 1b from a cylinder containing liquefied hydrogen sulfide with a pressure reducing valve and a flow meter, and was blown into the suction port 1a of the cleaning device 1. Note that the cleaning chemical solution was not sprayed from the spray means 3 (spray nozzle).
[0119]
  Air flow is 3m³ The experiment was conducted at a pressure loss of 30 mm aq at a setting of / min. Ten minutes after the start of air blowing, the hydrogen sulfide concentration at the inlet 1a was measured with a Kitagawa type gas detector tube and found to be 4000 ppm.
Met. On the other hand, the hydrogen sulfide concentration was measured in the same manner at the exhaust port 9 of the cleaning device, but could not be detected. The same analysis was performed every hour from the start of the experiment to 3 hours, but no hydrogen sulfide was detected at the exhaust port 9 of the cleaning device.
[0120]
  However, when 3 hours and 45 minutes had passed, the hydrogen sulfide odor began to drift strongly around the equipment. Therefore, in order to prevent danger, the supply of hydrogen sulfide was stopped, and 2 kg of preliminary cleaning chemicals were added to completely sulfidize. It was operated only by air blowing until hydrogen was not detected from the exhaust port. The reason why the hydrogen sulfide could not be removed after a certain period of time was that the neutralization reaction equivalent of the cleaning chemical solution became zero, and when it contains a high concentration of hydrogen sulfide such as biogas, the cleaning chemical solution used was It was found that the chemical solution is unsuitable and requires a greatly improved desulfurization capacity.
(Example 7)
  Using the same cleaning apparatus (FIG. 1) having a layer containing a gas cleaning filler as in Example 6, removal of hydrogen sulfide gas was attempted.
[0121]
  A certain amount of hydrogen sulfide is mixed into the air sucked by the suction blower 1b from the liquefied hydrogen sulfide cylinder by means of a pressure reducing valve and a flow meter. Further, sulfurous acid gas is reacted with hydrogen sulfide from the liquefied sulfurous acid gas cylinder in an equivalent amount of 95. % Equivalent to 1800ppm
Was blown from the sulfurous acid gas supply port 8a. Note that the cleaning chemical solution was not sprayed from the spraying means 3 in the cleaning apparatus.
[0122]
  As cleaning chemicals, 2% of “amphiphilic solvent” triethylene glycol dimethyl ether, 10% of caustic soda, 5% of triethanolamine, 3% of sodium chloride as a salting-out agent, iodine and polyvinyl pyrrolidone This complex was made into an aqueous solution in which 0.01% in terms of iodine was mixed and dissolved. 50 kg of cleaning chemical was prepared. 1, 3, 4, 7, 10, and 15 hours after the start of air blowing, the concentrations of hydrogen sulfide and sulfurous acid gas were measured at the exhaust port 9 of the cleaning device using a Kitagawa gas detector tube, respectively. As a result, neither hydrogen sulfide nor sulfurous acid gas was detected. The cleaning chemical liquid collected at the bottom of the cleaning apparatus in FIG. 1 was changed to a slurry containing white turbid sulfur compared to before the start of operation, and a considerable amount of sulfur was precipitated. This sulfur content can be easily separated and recovered by ordinary agglomeration precipitation, washing, and filtration, and can be reused as a raw material for sulfite gas. In addition, it was confirmed that the cleaning chemical solution can be reused.
[0123]
【The invention's effect】
  According to the present invention, conventionally, it is difficult to remove from polluting gas, it is accompanied by malodor or harmful, pollutant such as molecular or aerosol, or mixed pollutants thereof, or further Hydrophobic contaminants and the like can be removed easily, safely and completely at the same time, and less power, irrigation water, chemicals, etc. are used. Further, according to the present invention, it is possible to clean the pollutant gas without leaking harmful pollutants to the environment, and there is an effect of reducing the risk of occurrence of a secondary disaster.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view schematically showing an example of a contaminated gas cleaning apparatus of the present invention.
[Explanation of symbols]
1 Cleaning device
1a Inlet
1b Inhalation blower
1c Piping
2 Layer containing gas cleaning filler
2a droplet
2b Filler support frame
2c Gas cleaning filler
3 Spraying means
3a Mist (spray)
4 Supply means
4a Liquid pump
5 Polluted gas
6 Cleaning chemical tank
6a1, 6a2, 6a3 piping
6b1, 6b2, 6b3 valves
61 Cleaning chemical tank
61a Compressor for pressurization
7 Cleaning chemical storage tank
7a Pollutant
7b1, 7b2 piping
7c1, 7c2 valve
8 Sulfurous acid gas supply port, 8b piping
9, 9a Exhaust port

Claims (2)

A layer including a cleaning device having a cleaning chemical solution supplying means for supplying a cleaning chemical solution to the layer including the gas cleaning filler and having a layer including the gas cleaning filler, and including the gas cleaning filler. In addition to the cleaning chemical solution supply means for supplying the cleaning chemical solution, spray means for the cleaning chemical solution that is the same as or different from the cleaning chemical solution is disposed in the cleaning device or separately from the cleaning device, and further A pollutant gas inlet is disposed upstream of the means, and the pollutant gas introduced from the inlet is sprayed with a cleaning chemical by the spraying means and then passed through the layer containing the gas cleaning filler. A cleaning system for contaminated gas, wherein the spraying means is a spraying means capable of spraying the cleaning chemical liquid as a mist having an average particle size of 30 μm or less, and the gas cleaning filler is mainly composed of fibrous fibers. A pretreatment of impregnating a paper grain to be impregnated with one of the following treatments A to C or an aqueous solution containing phosphoric acid or phosphoric acid and urea, followed by drying and heat treatment at a temperature of 130 to 170 ° C. The gas obtained by applying each of the above treatments to the layer containing the gas cleaning filler, which is made of paper particles subjected to one type of treatment selected from the following A to C treatments One or more kinds of cleaning fillers are laminated, put into a bag, and the upper and lower surfaces are filled into an air-permeable cartridge. wash liquor containing an amphiphilic organic compound of 0.99 ° C. or more water-soluble are impregnated or supplied Ri Na, the gas as further liquid surface of the cleaning chemical liquid is positioned lower than the layer containing the gas cleaning filler Cleaning chemicals that have passed through the layer containing the cleaning filler accumulate. A cleaning chemical solution tank, and a cleaning chemical solution storage tank, a water tank or a contaminant treatment tank for separating contaminants floating in the cleaning chemical solution tank .
Treatment A: One or two of polyvinyl alcohol and solubilized chitosan, and a fibrous fiber having 2 or more methylol groups or methoxymethyl groups in which no active hydrogen atom is bonded to the nitrogen atom in the molecule A treatment of impregnating an aqueous solution containing at least one of cross-linking agents and an acid catalyst or further methyl alcohol as essential components, followed by drying and heat treatment to impart water resistance and hardness.
B treatment: A treatment for impregnating an aqueous solution containing an acid catalyst as an essential component, drying while leaving moisture, and reacting gaseous formaldehyde at 100 ° C. or lower to impart water resistance.
C treatment: impregnated with one or two of polyvinyl alcohol and solubilized chitosan and an aqueous solution containing an acid catalyst as an essential component, dried by leaving moisture, and reacted with gaseous formaldehyde at 100 ° C or lower Treatment to impart water resistance and hardness. Contaminating gas is introduced into a cleaning system comprising a cleaning device comprising a spraying means with a cleaning chemical solution and a layer containing a gas cleaning filler, or a cleaning system having spraying means separately from the cleaning device and the cleaning device, A method for cleaning a contaminated gas, in which the cleaning gas is sprayed by a spraying means and then passed through the layer containing the gas cleaning filler to perform cleaning, wherein the gas cleaning filler is mainly composed of fibrous fibers. The following A to C treatment A treatment: one or two of polyvinyl alcohol and solubilized chitosan, and methylol in which no active hydrogen atom is bonded to the nitrogen atom in the molecule An aqueous solution containing one or more of the fibrous fiber cross-linking agents having two or more groups or methoxymethyl groups, an acid accelerator, and further methyl alcohol as essential components. And, subjected to drying and heat treatment, to impart water resistance and hardness treatment.
B treatment: impregnated with an aqueous solution containing an acid accelerator as an essential component, dried to leave moisture, and added gaseous formaldehyde to 100
A process of reacting at a temperature of ℃ or less to impart water resistance.
C treatment: impregnated with one or two of polyvinyl alcohol and solubilized chitosan and an aqueous solution containing an acid accelerator as an essential component, dried to leave moisture, and added gaseous formaldehyde to 100
A treatment that gives water resistance and hardness by reacting at ℃ or below.
After impregnating one treatment selected from the above or an aqueous solution containing phosphoric acid or phosphoric acid and urea, and performing a pretreatment for drying and heat treatment at a temperature of 130 to 170 ° C., the above-mentioned AC 1 type of gas cleaning filler obtained by applying each of the above treatments to the layer containing the gas cleaning filler, which is made of paper particles subjected to one type of processing selected from the processing. The above is constituted by one or two or more means of laminating, bagging and filling the air-permeable cartridge on the upper and lower surfaces, and has a boiling point of 150.
℃ becomes impregnated or supplying wash liquor containing more water-soluble amphiphilic organic compound, later further the wash liquor, is passed through the layer containing the gas cleaning fillers, and stored in the washing chemical tank, A method for cleaning a pollutant gas , wherein the pollutant floating in the cleaning chemical solution tank is stored in a pollutant treatment tank and the pollutant is further separated .

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