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KR950004168B1 - Treatment method for waste water containning nitrophenol and derivatives - Google Patents

Treatment method for waste water containning nitrophenol and derivatives Download PDF

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KR950004168B1
KR950004168B1 KR1019910011809A KR910011809A KR950004168B1 KR 950004168 B1 KR950004168 B1 KR 950004168B1 KR 1019910011809 A KR1019910011809 A KR 1019910011809A KR 910011809 A KR910011809 A KR 910011809A KR 950004168 B1 KR950004168 B1 KR 950004168B1
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wastewater
nitrophenol
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dinitro
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KR930002246A (en
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이영섭
이경열
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삼성종합화학주식회사
성평건
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    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/52Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
    • C02F1/54Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using organic material

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  • Environmental & Geological Engineering (AREA)
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  • Separation Of Suspended Particles By Flocculating Agents (AREA)

Abstract

내용 없음.No content.

Description

니트로 페놀 및 그 유도체를 함유하는 폐수정화 처리방법Wastewater Purification Process Containing Nitrophenol And Its Derivatives

본 발명은 니트로페놀과 그 유도체를 함유하는 폐수의 정화처리방법에 관한 것으로 보다 상세하게는 스틸렌, α- 메틸스틸렌, P - 메틸스틸렌, 디 비닐 벤젠과 같은 비닐방향족 화합물(vinyl aromatic compounds)를 생산하는 석유 화학 프랜트에서 중합금지제등으로 사용되고 있는 다음 일반식의 니트로페놀 화합물을 함유하는 폐수를 효율적으로 정화처리하는 방법에 관한 것이다.The present invention relates to a method for purifying wastewater containing nitrophenol and its derivatives, and more particularly, to produce vinyl aromatic compounds such as styrene, α-methylstyrene, P-methylstyrene, and divinyl benzene. The present invention relates to a method for efficiently purifying wastewater containing nitrophenol compounds of the following general formulas used as polymerization inhibitors in petrochemical plants.

(R1, R3, R5는 니트로, 수소 또는 알킬기, R2, R4는 수소 또는 니트로기, 그리고 R1, R2, R3, R4, R5중에서 적어도 두개는 니트로기를 함유한다.)(R 1 , R 3 , R 5 are nitro, hydrogen or alkyl groups, R 2 , R 4 are hydrogen or nitro groups, and at least two of R 1 , R 2 , R 3 , R 4 , R 5 contain nitro groups .)

(상기 일반식 화합물인 니트로페놀 및 그 유도체로는 니트로페놀, 디니트로페놀, 트리니트로페놀, 또는 할로겐기, 알킬기, 아미노기, 카복실기로 치환된 방향족 고리를 가진 페놀 유도체이다)(The above-mentioned general formula nitrophenol and its derivatives are nitrophenol, dinitrophenol, trinitrophenol, or phenol derivative having an aromatic ring substituted with halogen, alkyl, amino, carboxyl group)

석유화학 프랜트에서, 예를들면 스틸렌모노머(이하 SM이라함) 제조공장에서는 합성 SM 제품의 증류정제 과정에서 자체중합 발생을 방지하고자 상기 일반식의 디니트로 올소크레졸, 디니토로 파라크레졸을 중합금지제로 사용하게 되는데, 예를들면 3,5-디니트로-올소-크레졸, 4-6-디니트로-올소-크레졸, 2,6-디니트로-파라-크레졸 등을 사용하며 통상 2,6-디니트로-P-크레졸(이하 DNPC라함) 화합물을 사용하고 있다. DNPC는 짙은 노란색을 띠는 플레이크 형태의 결정체로써 에틸벤젠에 용해시켜 농도를 조절한후 SM의 증류정제공정에 투입하게 된다.In petrochemical plants, for example, the styrene monomer (hereinafter referred to as SM) manufacturing plant prohibits the polymerization of dinitro olsocresol and dinito paracresol of the general formula to prevent the occurrence of self-polymerization during the distillation and purification of synthetic SM products. Zero, for example, 3,5-dinitro-olso-cresol, 4-6-dinitro-olso-cresol, 2,6-dinitro-para-cresol, and the like. Nitro-P-cresol (hereinafter referred to as DNPC) compound is used. DNPC is a dark yellow flake crystal that is dissolved in ethylbenzene and adjusted in concentration before being introduced into SM distillation purification process.

일반적으로 DNPC 폐수의 발생원인은 ① 중합금지제를 녹이는 과정에서 작업대에 흘리거나 ② 에틸벤젠에 용해된 DNPC 용액을 저장조에 이송하는 Pump의 수선시 또는 장치의 이음새 결함등에 의해 발생하거나 ③ 특히 장치 세척 또는 우천시 빗물 또는 주변기기 세척용수와 함께 씻겨 배수구를 따라 흘러가게 된다. DNPC는 물에 대한 용해도가 상온에서 0.04로서, 물에 거의 녹지 않는다고 방심할 수 있겠으나, 이를 바꿔말하면 DNPC 1g을 완전히 포화상태로 용해시키기 위해서는 이론상 2.5ℓ의 물이 필요할 뿐만 아니라 이 농도에서 높은 발색도(노란색)를 보이기 때문에 오히려 소량의 DNPC 폐기로도 다량의 색깔오염폐수를 발생하게 된다. 따라서 버려진 DNPC는 물을 만나게 되면 소량이 용해되면서 지속적으로 DNPC 고유의 색깔을 나타내기 때문에 이를 물로써 희석제거하기 위해서는 막대한 량의 물이 필요하게 된다.Generally, the cause of DNPC wastewater is caused by ① flowing into the workbench in the process of dissolving the polymerization inhibitor or ② caused by the repair of the pump which transfers the DNPC solution dissolved in ethylbenzene to the storage tank or by the defect of the seam of the equipment. Or in rainy weather, it is washed with rainwater or peripheral cleaning water and flows along the drain. DNPC has a solubility in water of 0.04 at room temperature, so it can be said that it is hardly soluble in water.In other words, DNPC requires theoretically 2.5 L of water to completely dissolve 1g of DNPC. Because of its yellow color, even a small amount of DNPC disposal generates a large amount of color polluted water. Therefore, when the discarded DNPC meets the water and dissolves in small amounts, the DNPC continuously displays its own color. Therefore, in order to dilute it with water, a large amount of water is required.

발생된 폐수는 그 자체만으로는 환경보전법상의 BOD, COD 기준치에는 미달된다 할지라도 짙은 색깔 때문에 그대로 방류할 수는 없는 것이다. 이같은 DNPC 함유폐수는 흡착법 등의 기존의 폐수처리 시설로서는 완전한 정화처리가 어립고 별도의 시설투자가 필요한 실정이었다.The generated wastewater by itself cannot be discharged as it is due to the dark color, even if it falls short of the BOD and COD standards. Such wastewater containing DNPC was difficult to be completely purified by existing wastewater treatment facilities such as adsorption, and additional facility investment was required.

종래 DNPC 폐수처리 방법으로는 활성탄이나 실리카/알루미나와 같은 흡착탑을 이용한 흡착법이 있는바이는 다량의 폐수를 연속처리할 수 있는 장점은 있으나 폐흡착제의 별도 처리가 요구되는 단점이 있고, 미국특허 4,197,198 등에서는 오존을 이용한 화학적처리법을 사용하였으나 이 역시 2차폐기물이 발생하고 투자비 및 운전비가 고가이며 처리효과가 불확실한 단점이 있으며, 또한 DNPC 폐수를 공정에 재투입하는 공정 회수법이 있으나 제품품질에 영향을 주기쉽고 처리량에도 한계가 있는 결점이 있었다.Conventional DNPC wastewater treatment method has an advantage that the adsorption method using an adsorption column such as activated carbon or silica / alumina has the advantage of being able to continuously process a large amount of wastewater, but there is a disadvantage that requires separate treatment of the waste adsorbent, US Patent 4,197,198, etc. Has used ozone chemical treatment method, but it also has secondary disadvantages, high investment cost and operation cost, and unclear treatment effect. Also, there is a process recovery method to reintroduce DNPC wastewater into the process, but it does not affect the product quality. There were drawbacks that were easy to cycle and had limited throughput.

따라서 본 발명은 이같은 종래의 방법에서의 단점을 제거한 신규한 화학적 처리방법에 따른 DNPC 폐수정화 처리방법을 제공하는 것이다. 즉, 본 발명은 DNPC 폐수를 정화처리함에 있어 폐수에 NaOCl 용액 0.3 내지 1.2용적% 및 Cu염 용액 2 내지 10용적%로 투입혼합하고, 여기에 알카리 용액을 적당량 가하여 전체의 pH가 6 내지 7이 되도록한 후, 발생된 침전물을 응집여과 처리함을 특징으로 한 폐수정화 처리방법이다.Accordingly, the present invention provides a method for treating DNPC wastewater purification according to a novel chemical treatment method which eliminates the disadvantages of such a conventional method. That is, the present invention is mixed with 0.3 to 1.2% by volume of NaOCl solution and 2 to 10% by volume of Cu salt solution in the treatment of DNPC wastewater, and the total pH is 6-7 by adding an appropriate amount of alkali solution. After that, the waste water purification treatment method characterized in that the precipitate produced by coagulation filtration treatment.

본 발명에서 사용하는 Cu염은 CuSO4, CuNO3등이며 이때 Cu염 수용액은 폐수중의 DNPC와 결합하여 착화물을 형성하고 침전물로 침전되도록 하는 역할을 하는 것으로 10% 수용액으로 하여 폐수용적에 대해 2내지 10용적%로 투입하는 것이 좋다. 이는 투입량이 너무 적으면 DNPC와의 착화합물 형성이 부족하게 되어 정화처리 효과가 낮아지고, 너무 과하면 착화합물 형성은 만족스러우나 처리액의 pH가 산성쪽으로 기울게 되어 차후 pH 6 내지 7로 조정하기 위한 NaOH 투입량이 증가하게 된다.Cu salt used in the present invention is CuSO 4 , CuNO 3, etc. At this time, the aqueous solution of Cu salt combines with DNPC in the wastewater to form a complex and precipitates as a precipitate, and the 10% aqueous solution to the waste water volume 2 to 10% by volume is recommended. If the input amount is too small, the formation of complex compound with DNPC is insufficient and the purification treatment effect is low. If the input amount is too high, the formation of the complex compound is satisfactory. Done.

본 발명에서 사용하는 NaOCl 용액은 일종의 촉매작용을 하는 것으로 Cu염이 DNPC와 반응하여 착화합물을 형성하는 것을 촉진시키고 그 반응물이 신속히 침전되도록 한다. 이것은 시판중인 10% 수용액을 사용하고 사용량은 폐수용적에 대해 0.3 내지 1.2용적%를 투입한다. 이의 투입량이 너무 적을 경우에는 DNPC와 Cu염 착학합물 형성 및 침전이 원활치 못하고 너무 많을 경우에는 정화처리후의 정화수에 이들이 남아있게 되어 미생물의 성장을 억제하는 등의 부작용을 일으킬 수도 있어 바람직하지 못하다.The NaOCl solution used in the present invention catalyzes a kind of catalysis and promotes the formation of the complex by reacting the Cu salt with DNPC and allows the reactant to precipitate rapidly. This uses a commercially available 10% aqueous solution and the amount used is 0.3 to 1.2% by volume based on the wastewater volume. If the input amount is too small, the formation and precipitation of DNPC and Cu salt complexes are not smooth and if too much, they remain in the purified water after the purification treatment, which may cause side effects such as inhibiting the growth of microorganisms.

본 발명에서는 pH 조절용으로 사용하는 NaOH 용액은 그 사용농도를 한정할 필요는 없으나 NaOC1과 CuSO4로 처리한 폐수의 pH가 중성인 6 내지 7이 되도록 적정량으로 투입하는 것이 중요하다. NaOH 처리전의 폐수의 pH는 약 4-5로써 약산성을 띠는바 따라서 NaOH의 투입량이 과소하면 폐수는 여전히 산성을 띠어 침전물의 침전이 신속하지 못하게 되고 너무 투입하면 폐수는 중성을 넘어 알카리성을 띠게 되어 폐수의 색상이 오히려 흑색으로 변하게 된다.In the present invention, the NaOH solution used for pH adjustment does not need to limit its concentration, but it is important to add an appropriate amount so that the pH of the wastewater treated with NaOC1 and CuSO 4 is 6 to 7 being neutral. The pH of the wastewater before treatment with NaOH is about 4-5, so it is weakly acidic. Therefore, if the amount of NaOH is too low, the wastewater is still acidic and the precipitate is not quickly precipitated. The color of the waste water turns rather black.

본 발명에서 상술한 방법에 따라 처리된 DNPC 폐수는 DNPC가 Cu염 화합물과 착화합물을 형성하여 청색의 침전물로 급속히 가라앉게 된다. 이 침전물을 수거하는 방법은 특별히 한정할 필요가 없이 통상의 응집여과처리 등의 방법에 따라 제거하면 족하다.In the present invention, the DNPC wastewater treated according to the above-described method rapidly forms a complex with the DN salts of Cu salt compound and rapidly sinks into a blue precipitate. There is no need to specifically limit the method of collecting this precipitate, and it is sufficient to remove it according to methods, such as a conventional coagulation filtration process.

본 발명에 따라 처리된 DNPC 폐수의 정화수는 DNPC가 거의 l00% 제거되는 효과를 갖지만 처리수의 상층부에 일부 NaOCl이 남아있을 수 있는바, 이는 사실 무시해도 가능한 양이지만 미생물성장 억제기능이 있는 점을 감안하여 이를 마저 제거고져할 경우에는 소정량의 Na2S2O3용액으로 중화처리하면 된다.Purified water of the DNPC wastewater treated according to the present invention has the effect of removing approximately 10,000% of DNPC, but some NaOCl may remain in the upper part of the treated water, which is in fact negligible, but it has a function of inhibiting microbial growth. In consideration of this, even if it is removed, it may be neutralized with a predetermined amount of Na 2 S 2 O 3 solution.

본 발명을 실시하기 위하여는 어떤 새로운 장치설비가 필요치 않고 기존의 폐수처리시설의 일부를 그대로 활용하거나 별도의 간단한 용기에서 실시하는 것이면 족하다.In order to implement the present invention, no new equipment is required, and a part of the existing wastewater treatment facility may be used as it is or may be performed in a separate simple container.

따라서 본 발명은 기존공정 및 폐수처리시설을 100% 활용하면서 폐수중의 DNPC를 효과적으로 완벽하게 정화처리할 수 있으며, 작업이 간단하고 화학약품의 종류와 사용량이 적은 경계적 잇점이 있으며, 독성이 없고 2차 폐기물의 소량발생으로 소각이 가능하고 물의 회수에 의한 공업용수로 재활용이 가능한 잇점이 있다.Therefore, the present invention can effectively and completely clean the DNPC in the wastewater while utilizing 100% of the existing process and wastewater treatment facilities, the operation is simple, there is a boundary advantage of less type and amount of chemicals, there is no toxicity It is possible to incinerate small amount of secondary waste and recycle it to industrial water by water recovery.

이하에 간단히 실시예를 들고자 한다.An example will be given briefly below.

(실시예)(Example)

DNPC가 거의 포화상태로 용해되어 있는 짙은 노란색을 띤 폐수 100ℓ를 용기내에 안치하고 여기에 10% NaOCl 용액 600cc를 투입하여 혼합한 결과 pH가 8.5였다. 상기 용액에 10% CuSO4ㆍ5H2O 용액 4000cc를 넣고 혼합하니 전체용액은 청색로 바뀌고 이어서 청색의 침전물이 발생되기 시작하였고 이때의 pH는 4.5 정도였다. 여기에 NaOH 용액을 서서히 가하면서 pH가 6.5가 되었을때 이의 투입을 중단한 결과 청색의 침전물은 신속히 가라앉았고 맑은물이 위에 위치하였다. 청색의 침전물을 슬러지상태로 용기밑면에서 드레인하여 분리한 후 응집여과기에서 처리한 결과 약 50g의 착화합물 분말을 수거해낼 수 있었다. 침전물을 제외시킨 상층부의 맑은물에 DNPC의 잔류 여부를 확인하기 위하여 UV분석을 행한 결과 미처리 폐수의 경우는 스펙트럼으로 448nm에서 DNPC의 피크를 볼 수 있었으나 처리수의 경우는 피크가 전혀 나타나지 않아 DNPC가 완벽히 제거되었음을 확인할 수 있었다.100 l of dark yellow wastewater, in which DNPC was dissolved almost in a saturated state, was placed in a vessel, and mixed with 600 cc of 10% NaOCl solution. 4000cc of 10% CuSO 4 .5H 2 O solution was added to the solution, and the mixture was changed to blue. Then, blue precipitate began to occur, and the pH was about 4.5. When the NaOH solution was slowly added thereto and the pH was 6.5, the feeding was stopped. As a result, the blue precipitate quickly settled and the clear water was positioned above. About 50 g of the complex powder could be collected by draining the blue precipitate from the bottom of the container in a sludge state and treating it with a coagulation filter. UV analysis was carried out to confirm the presence of DNPC in the clear water of the upper layer, except for the sediment. As a result, the peaks of DNPC were found at 448 nm in the case of untreated wastewater. It was confirmed that it was completely removed.

Claims (7)

비닐 방향족 화합물의 제조공정에서 발생되는 니트로페놀 및 그 유도체를 함유하는 페수정화 처리방법에 있어서, 페수에 대해 NaOCl 용액 및 Cu염 용액을 투입 혼합하고 알카리 용액으로 전체 pH를 중성으로 조정하여 침전물을 얻고 발생된 침전물을 응집 여과처리함을 특징으로 하는 폐수정화 처리방법.In the wastewater purification method containing nitrophenol and derivatives thereof produced in the production process of a vinyl aromatic compound, NaOCl solution and Cu salt solution are added and mixed with waste water, and the total pH is adjusted to neutral with an alkaline solution to obtain a precipitate. Wastewater purification treatment method characterized in that the precipitate produced by coagulation filtration. 제1항에 있어서, 니트로페놀 및 그 유도체는 하기 일반식인 것을 특징으로 하는 폐수정화 처리방법.The method for treating wastewater purification according to claim 1, wherein the nitrophenol and its derivatives are of the following general formula. (R1,R3,R5는 니트로, 수소 또는 알킬기, R2,R4는 수소 또는 니트로기, 그리고 R1,R2,R3,(R 1 , R 3 , R 5 is nitro, hydrogen or alkyl group, R 2 , R 4 is hydrogen or nitro group, and R 1 , R 2 , R 3 , R4,R5중에서 적어도 두개는 니트로기를 함유한다.)At least two of R 4 and R 5 contain a nitro group.) 제1항에 있어서, NaOCl 용액은 폐수에 대해 0.3 내지 1.2용적%로 첨가하는 것을 특징으로 하는 폐수정화 처리방법.The method of claim 1, wherein the NaOCl solution is added at 0.3 to 1.2% by volume relative to the wastewater. 제1항에 있어서, Cu염 용액은 CuSO4또는 CuNO3이고 폐수에 대해 2 내지 10용적%로 첨가하는 것을 특징으로 하는 폐수정화 처리방법.The method of claim 1, wherein the Cu salt solution is CuSO 4 or CuNO 3 and is added at 2 to 10% by volume relative to the wastewater. 제2항에 있어서, 니트로페놀 및 그 유도체는 디니트로 올소(ortho) 크레졸과 디니트로 파라(para)크레졸로 구성된 디니트로 크레졸인 것을 특징으로 하는 폐수정화 처리방법.3. The method of claim 2, wherein the nitrophenol and its derivatives are dinitro cresols composed of dinitro ortho cresols and dinitro para cresols. 제5항에 있어서, 니트로페놀 및 그의 유도체는 2,6-디니트로-파라-크레졸인 것을 특징으로 하는 폐수정화 처리방법.The method of claim 5, wherein the nitrophenol and its derivatives are 2,6-dinitro-para-cresol. 제1항에 있어서, 니트로페놀 및 그 유도체는 2,6-디니트로-파라-크레졸이고, 폐수에 대해 NaOCl 0.3 대지 1.2용적%, Cu염 용액 2 내지 10용적%를 투입 혼합하고 NaOH 용액으로 전체 PH를 중성으로 조정하여 침전물을 얻고 발생된 침전물을 응집여과 처리하는 것을 특징으로 하는 폐수정화 처리방법.The method of claim 1, wherein the nitrophenol and its derivatives are 2,6-dinitro-para-cresol, in which 0.3 vol% NaOCl 1.2 vol% and 2 to 10 vol% Cu salt solution are added to the wastewater and mixed with NaOH solution. Adjusting the pH to neutral to obtain a precipitate and the waste water purification treatment method characterized in that the coagulation treatment of the generated precipitate.
KR1019910011809A 1991-07-11 1991-07-11 Treatment method for waste water containning nitrophenol and derivatives Expired - Lifetime KR950004168B1 (en)

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