CN1050064A - Acidifying process of paper black liquid with sulphur dioxide - Google Patents
Acidifying process of paper black liquid with sulphur dioxide Download PDFInfo
- Publication number
- CN1050064A CN1050064A CN 89106694 CN89106694A CN1050064A CN 1050064 A CN1050064 A CN 1050064A CN 89106694 CN89106694 CN 89106694 CN 89106694 A CN89106694 A CN 89106694A CN 1050064 A CN1050064 A CN 1050064A
- Authority
- CN
- China
- Prior art keywords
- lignin
- black liquor
- acidifying
- filtrate
- sulfur dioxide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- 238000000034 method Methods 0.000 title claims abstract description 24
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 title claims description 45
- 235000010269 sulphur dioxide Nutrition 0.000 title description 21
- 239000007788 liquid Substances 0.000 title description 11
- 239000004291 sulphur dioxide Substances 0.000 title description 4
- 229920005610 lignin Polymers 0.000 claims abstract description 38
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 claims abstract description 31
- 239000000706 filtrate Substances 0.000 claims abstract description 20
- 235000010265 sodium sulphite Nutrition 0.000 claims abstract description 15
- 239000003513 alkali Substances 0.000 claims abstract description 9
- 238000004537 pulping Methods 0.000 claims abstract description 6
- 238000002425 crystallisation Methods 0.000 claims abstract description 5
- 230000008025 crystallization Effects 0.000 claims abstract description 5
- 238000010411 cooking Methods 0.000 claims abstract description 4
- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 claims abstract description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims abstract description 3
- 239000002585 base Substances 0.000 claims abstract description 3
- 238000002360 preparation method Methods 0.000 claims abstract description 3
- 239000011734 sodium Substances 0.000 claims abstract description 3
- 229910052708 sodium Inorganic materials 0.000 claims abstract description 3
- 239000002253 acid Substances 0.000 claims description 10
- 238000001914 filtration Methods 0.000 claims description 7
- 238000001556 precipitation Methods 0.000 claims description 6
- 239000002244 precipitate Substances 0.000 claims description 3
- 230000020477 pH reduction Effects 0.000 claims description 2
- 239000002994 raw material Substances 0.000 abstract description 4
- 238000012545 processing Methods 0.000 abstract description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical group [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 10
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 7
- 239000007789 gas Substances 0.000 description 7
- MBMLMWLHJBBADN-UHFFFAOYSA-N Ferrous sulfide Chemical compound [Fe]=S MBMLMWLHJBBADN-UHFFFAOYSA-N 0.000 description 6
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 4
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 4
- 230000008901 benefit Effects 0.000 description 4
- 239000003245 coal Substances 0.000 description 4
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 3
- 239000005864 Sulphur Substances 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 238000003916 acid precipitation Methods 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000011109 contamination Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000003344 environmental pollutant Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 231100000719 pollutant Toxicity 0.000 description 2
- NIFIFKQPDTWWGU-UHFFFAOYSA-N pyrite Chemical compound [Fe+2].[S-][S-] NIFIFKQPDTWWGU-UHFFFAOYSA-N 0.000 description 2
- 229910052683 pyrite Inorganic materials 0.000 description 2
- 239000011028 pyrite Substances 0.000 description 2
- 239000011780 sodium chloride Substances 0.000 description 2
- 239000010902 straw Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 235000014676 Phragmites communis Nutrition 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- 241000209140 Triticum Species 0.000 description 1
- 235000021307 Triticum Nutrition 0.000 description 1
- 238000010306 acid treatment Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000002309 gasification Methods 0.000 description 1
- 239000003673 groundwater Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910052740 iodine Inorganic materials 0.000 description 1
- 239000011630 iodine Substances 0.000 description 1
- 239000010893 paper waste Substances 0.000 description 1
- 238000011112 process operation Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Paper (AREA)
Abstract
The invention provides a kind of new method with SO 2 acidifying processing alkali paper-making black liquor, lignin is by heavy filtered and recycled in the black liquor, and filtrate can be reclaimed sodium sulfite through evaporative crystallization, also can be directly used in the cooking liquor of preparation sodium base bisulfite pulping.This method raw material sources are extensive, method is easy, small investment, not only reclaimed lignin but also be recovered into alkali indirectly, and are good in economic efficiency, are easy to promote the use of in medium and small paper mill.
Description
The present invention relates to that paper waste in the environmental protection is handled and the technical field of changing rejected material to useful resource.
China has the thousands of families in middle-size and small-size paper mill now, discharges high-concentration waste liquid in the soda pulping process operation, so-called black liquor, severe contamination ground water environment.Lignin is one of main component in the black liquor, can reduce pollutant emission effectively behind the black liquor recovery lignin.And existing sulfuric acid and salt acid treatment alkali paper-making black liquor, because acid is in short supply, many producers can not get these raw material sources and can't recycle; Another shortcoming of sulfuric acid or salt acid system is to exist with sodium chloride or NaOH form in the filtrate of NaOH composition behind separating lignin contained of black liquor Central Plains, does not have to recycle to be worth.
At the problems referred to above, the SO 2 acidifying system has been set up in research by experiment.This method can make black liquor obtain handling with the raw material that is easy to get, easy method, less investment with lignin recovery.This method if can be promoted in the whole nation, can improve the situation of China's water environment severe contamination effectively.The lignin purposes is wider simultaneously, and it also is very considerable recycling its economic benefit of this resource.This method can also reclaim with the sodium sulfite form dropping into NaOH in producing, and reach the purpose that alkali reclaims indirectly, and has fundamentally changed sulfuric acid and the salt acid system can only reclaim the situation that lignin can not reclaim alkali.
This method is applicable to the wheat straw to be raw material, the black liquor that soda pulping process produced.Alkaline pulping black liquor such as straw, reed also might use this law.Representational black liquor composition: content of lignin＞2%, Baume degrees 6-12, pH＞7.5-12, ash content＜5%.
This method is characterised in that with sulfur dioxide and makes the black liquor acidifying, precipitates lignin under heat tracing, after filtration separating lignin and contain the acid filtrate of inferior sulfate radical.The pH scope of black liquor acidifying is below 4, Baume degrees 5-6, temperature 50-70 ℃.Acid filtrate behind the filtration lignin neutralizes with alkali, reclaims sodium sulfite or is directly used in the cooking liquor of preparing sodium base bisulfite pulping through evaporative crystallization.
This method key step:
1, roasting pyrite (also available coal troilite, sulphur or the sulfur dioxide liquid of containing gasifies) produces sulfur dioxide gas;
2, make that it is water-soluble, sulfurous acid or sodium sulfite solution generate the acid solution that contains sulfurous acid, with in the above-mentioned solution and alkaline black liquor or directly feed sulfur dioxide form the solution system that contains sulfurous acid in black liquor, makes the following lignin that precipitates in pH＜4;
3, the reaction of acid precipitation lignin should be 5-6 and heating at Baume degrees;
4, isolated by filtration lignin, with dry after the hot wash lignin product;
5, the filtrate behind the isolated by filtration lignin can be reclaimed sodium sulfite wherein through further using in the alkali and the evaporative crystallization processing; Also filtrate being directly used in can be made the cooking liquor composition of Arbiso process papermaking.
Its advantage of acidifying process of paper black liquid with sulphur dioxide and good effect are:
1, use troilite or close the coal troilite and prepare sulfur dioxide, its wide material sources are easy to get;
2, easy, the small investment, with low cost of sulfur dioxide preparation method;
3, all alkali paper-making factories that can not get sulfuric acid or hydrochloric acid supply easily way prepare sulfur dioxide voluntarily, to reach the purpose of handling black liquor.Therefore this method all can be applicable in middle-size and small-size paper mill;
4, lignin is of many uses, can produce multiple afterproduct, has favorable economic benefit and development prospect;
5, the SO 2 acidifying method is handled the black liquor system, makes it have the condition that can further recycle owing to generating sodium sulfite with practical value in the filtrate behind separating lignin.Crystallizable recovery sodium sulfite also can be directly used in slurrying, thereby realizes not only reclaiming lignin but also recycle the two of sodium sulfite and reclaim from black liquor, and is good in economic efficiency.And with hydrochloric acid or sulfuric acid precipitation separating lignin, the filtrate that generates sodium chloride-containing or sodium sulphate does not possess the condition that is recycled;
6, because black liquor is able to abundant comprehensive utilization, has reduced pollutant emission significantly, and had environmental benefit well.
Accompanying drawing is the schematic diagram of acidifying process of paper black liquid with sulphur dioxide.
Embodiment:
1, produces SO 2 acidifying with roasting pyrite and handle black liquor
The troilite powder heating burns sulfur dioxide gas, gas is introduced in the 250ml black liquor black liquor pH10.5, Baume degrees 6.5.Through reaction (heat up 60 ℃, be incubated 3 hours), 16.6 gram lignin precipitations are separated out.Filter filtrate pH3.5, inferior sulfate radical concentration 14 grams per liters.
2, contain the coal troilite powder with roasting and produce SO 2 acidifying processing black liquor
Heating contains the coal troilite powder, introduces in 25 ℃ of black liquor of 300ml liquid pH10.95, Baume degrees 6.5 burning sulfur dioxide gas.Separate out through reaction (50 ℃ of insulations 2 hours heat up) lignin precipitation.Filter filtrate pH4.0, chemical oxygen demand cod clearance 53%.Lignin weighs 18.6 grams.
3, burning sulphur produces SO 2 acidifying and handles black liquor
Sulphur 5 gram burns sulfur dioxide gas after the heating, gas is induced one in the 200ml black liquor black liquor pH10.95, Baume degrees 6.5.Separate out through reaction (65 ℃ of insulations 2 hours heat up) lignin precipitation.Filter, lignin weighs 8 grams.
4, with sulfur dioxide liquid gasification acidification black liquor
Sulfur dioxide is fed in the 500ml black liquor black liquor pH8.5, Baume degrees 6.5 with 0.5 liter/minute flow velocity.Ventilate after 20 minutes, heat up 60 ℃, lignin is separated out from solution.Filter, filtrate pH2.26, chemical oxygen demand cod clearance 65%, lignin weigh 31.11 grams, and filtrate Central Asia sulfate concentration is 31.4 grams per liters.
5, absorb behind the sulfur dioxide again and the black liquor phase reaction with water
Sulfur dioxide gas is fed in the water, become the sulfurous acid aqueous solution after making water absorb sulfur dioxide.The 3380ml black liquor, pour 6760ml pH into and be in 1.52 the sulfurous acid aqueous solution.The lignin precipitation is separated out, and filtrate pH3.0 gets lignin 135 grams.
6, absorb behind the sulfur dioxide with sodium sulfite aqueous solution and black liquor (pH10.5, Baume degrees 7.1) phase reaction is made absorption liquid with the sodium sulfite of 1mol again, feed the sulfur dioxide of 0.25 liter of/minute flow velocity, ventilated 42 minutes, the pH value of 250ml absorption liquid is 1.9.
The sodium sulfite water liquid of 150ml pH1.9 is poured in the 100ml black liquor, reaction back (heat up 60 ℃, be incubated 30 minutes), the pH of mixed liquor reduces to 3.9, and the lignin precipitation is separated out.
7, separate out the extraction of sodium sulfite in the lignin rear filtrate
The 250ml black liquor adds 250ml water, is warming up to 60 ℃, and the feeding flow velocity is 0.5 liter/minute a sulfur dioxide, ventilates 12 minutes, 60 ℃ of insulations 1 hour, filters again.Separate out lignin and weigh 9 grams, filtrate pH2.0, amount of filtrate is 440ml.NaOH is added in the filtrate adjust pH to 7.1.Heating is steamed near and is done, and with alcohol flush away organic impurities, is dissolved in water again.Water is promptly having the sodium sulfite crystallization to separate out after the evaporation gradually.Sodium sulfite crystal 15.4 gram, record with the titrimetry of iodine titer and to contain sodium sulfite 41% in the crystal.
Claims (6)
1, a kind of method of acidification alkaline papermaking black liquor is characterized in that making the black liquor acidifying with sulfur dioxide, precipitates lignin under heat tracing, after filtration separating lignin and contain the acid filtrate of inferior sulfate radical.
2, method according to claim 1 is characterized in that black liquor acidifying pH scope is below 4.
3, method according to claim 1 and 2, the temperature of precipitation that it is characterized in that lignin is 50-70 ℃.
4, method according to claim 3, the Baume degrees that it is characterized in that the black liquor acid system is 5-6.
5, method according to claim 1, the acid filtrate that it is characterized in that filtering out behind the lignin neutralizes with alkali, reclaims sodium sulfite through evaporative crystallization.
6, method according to claim 1 is characterized in that filtering out the cooking liquor that acid filtrate behind the lignin can be directly used in the preparation sodium base bisulfite pulping.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 89106694 CN1017077B (en) | 1989-09-04 | 1989-09-04 | Treatment of black liquor from alkaline paper making by sulfur dioxide acidification method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 89106694 CN1017077B (en) | 1989-09-04 | 1989-09-04 | Treatment of black liquor from alkaline paper making by sulfur dioxide acidification method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1050064A true CN1050064A (en) | 1991-03-20 |
| CN1017077B CN1017077B (en) | 1992-06-17 |
Family
ID=4856833
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 89106694 Expired CN1017077B (en) | 1989-09-04 | 1989-09-04 | Treatment of black liquor from alkaline paper making by sulfur dioxide acidification method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1017077B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1059482C (en) * | 1996-09-10 | 2000-12-13 | 刘友会 | Alkali process for treating black liquor |
| CN1087045C (en) * | 2000-03-17 | 2002-07-03 | 中国科学院生态环境研究中心 | Cyclic process for treating black paper-making liquid of alkali pulping to recover useful resource |
| CN106905712A (en) * | 2017-03-21 | 2017-06-30 | 湖南师范大学 | A kind of method for preparing gum filler in utilization inorganic salts with alkali lignin |
| CN112708144A (en) * | 2020-11-30 | 2021-04-27 | 山东华泰纸业股份有限公司 | Method for producing lignin by using sulfur mud |
| US11407778B2 (en) | 2016-11-17 | 2022-08-09 | Upm-Kymmene Corporation | Method and an apparatus for recovering chemicals from an alkaline lignin material |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101831826B (en) * | 2010-06-22 | 2012-05-23 | 永州湘江纸业有限责任公司 | Method for crystallizing and evaporating papermaking pulping black liquor |
-
1989
- 1989-09-04 CN CN 89106694 patent/CN1017077B/en not_active Expired
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1059482C (en) * | 1996-09-10 | 2000-12-13 | 刘友会 | Alkali process for treating black liquor |
| CN1087045C (en) * | 2000-03-17 | 2002-07-03 | 中国科学院生态环境研究中心 | Cyclic process for treating black paper-making liquid of alkali pulping to recover useful resource |
| US11407778B2 (en) | 2016-11-17 | 2022-08-09 | Upm-Kymmene Corporation | Method and an apparatus for recovering chemicals from an alkaline lignin material |
| CN106905712A (en) * | 2017-03-21 | 2017-06-30 | 湖南师范大学 | A kind of method for preparing gum filler in utilization inorganic salts with alkali lignin |
| CN106905712B (en) * | 2017-03-21 | 2019-01-08 | 湖南师范大学 | A method of gum filler is prepared with alkali lignin using in inorganic salts |
| CN112708144A (en) * | 2020-11-30 | 2021-04-27 | 山东华泰纸业股份有限公司 | Method for producing lignin by using sulfur mud |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1017077B (en) | 1992-06-17 |
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