CN103588340B - Method for treating sodium-alkali desulfurization waste liquid by causticization-acidification method - Google Patents
Method for treating sodium-alkali desulfurization waste liquid by causticization-acidification method Download PDFInfo
- Publication number
- CN103588340B CN103588340B CN201310609080.6A CN201310609080A CN103588340B CN 103588340 B CN103588340 B CN 103588340B CN 201310609080 A CN201310609080 A CN 201310609080A CN 103588340 B CN103588340 B CN 103588340B
- Authority
- CN
- China
- Prior art keywords
- sodium
- filtrate
- thiocyanate
- desulfurization waste
- carbonate
- 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.)
- Expired - Fee Related
Links
- 238000000034 method Methods 0.000 title claims abstract description 56
- 239000002699 waste material Substances 0.000 title claims abstract description 46
- 238000006477 desulfuration reaction Methods 0.000 title claims abstract description 36
- 230000023556 desulfurization Effects 0.000 title claims abstract description 36
- 239000003513 alkali Substances 0.000 title claims abstract description 33
- 239000007788 liquid Substances 0.000 title claims abstract description 29
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims abstract description 92
- VGTPCRGMBIAPIM-UHFFFAOYSA-M sodium thiocyanate Chemical compound [Na+].[S-]C#N VGTPCRGMBIAPIM-UHFFFAOYSA-M 0.000 claims abstract description 52
- 239000011734 sodium Substances 0.000 claims abstract description 46
- 229910000029 sodium carbonate Inorganic materials 0.000 claims abstract description 46
- 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 32
- 229910052708 sodium Inorganic materials 0.000 claims abstract description 32
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 claims abstract description 25
- 239000012535 impurity Substances 0.000 claims abstract description 16
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims abstract description 13
- 229910052938 sodium sulfate Inorganic materials 0.000 claims abstract description 13
- 235000011152 sodium sulphate Nutrition 0.000 claims abstract description 13
- GBAOBIBJACZTNA-UHFFFAOYSA-L calcium sulfite Chemical compound [Ca+2].[O-]S([O-])=O GBAOBIBJACZTNA-UHFFFAOYSA-L 0.000 claims abstract description 12
- 235000010261 calcium sulphite Nutrition 0.000 claims abstract description 12
- 238000001816 cooling Methods 0.000 claims abstract description 11
- 239000007789 gas Substances 0.000 claims abstract description 10
- 238000010438 heat treatment Methods 0.000 claims abstract description 8
- 238000001704 evaporation Methods 0.000 claims abstract description 7
- 230000008020 evaporation Effects 0.000 claims abstract description 6
- 239000002244 precipitate Substances 0.000 claims abstract description 6
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 84
- 239000000706 filtrate Substances 0.000 claims description 41
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 claims description 39
- 238000006243 chemical reaction Methods 0.000 claims description 26
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims description 23
- 239000013078 crystal Substances 0.000 claims description 23
- 238000002425 crystallisation Methods 0.000 claims description 17
- PODWXQQNRWNDGD-UHFFFAOYSA-L sodium thiosulfate pentahydrate Chemical compound O.O.O.O.O.[Na+].[Na+].[O-]S([S-])(=O)=O PODWXQQNRWNDGD-UHFFFAOYSA-L 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- 239000000920 calcium hydroxide Substances 0.000 claims description 13
- 238000009993 causticizing Methods 0.000 claims description 13
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims description 12
- 229910000019 calcium carbonate Inorganic materials 0.000 claims description 12
- 235000011116 calcium hydroxide Nutrition 0.000 claims description 12
- 238000001556 precipitation Methods 0.000 claims description 12
- 235000010265 sodium sulphite Nutrition 0.000 claims description 12
- JNVCSEDACVAATK-UHFFFAOYSA-L [Ca+2].[S-]SSS[S-] Chemical compound [Ca+2].[S-]SSS[S-] JNVCSEDACVAATK-UHFFFAOYSA-L 0.000 claims description 11
- 239000012530 fluid Substances 0.000 claims description 11
- 229940051851 sulfurated lime Drugs 0.000 claims description 11
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 10
- 235000011089 carbon dioxide Nutrition 0.000 claims description 10
- 239000002535 acidifier Substances 0.000 claims description 9
- 239000002002 slurry Substances 0.000 claims description 9
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 claims description 8
- 239000011575 calcium Substances 0.000 claims description 8
- 229920001021 polysulfide Polymers 0.000 claims description 8
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 7
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 7
- 238000001914 filtration Methods 0.000 claims description 7
- 239000007787 solid Substances 0.000 claims description 7
- 238000010521 absorption reaction Methods 0.000 claims description 6
- 238000006386 neutralization reaction Methods 0.000 claims description 6
- 230000001590 oxidative effect Effects 0.000 claims description 6
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 5
- FKNQFGJONOIPTF-UHFFFAOYSA-N Sodium cation Chemical compound [Na+] FKNQFGJONOIPTF-UHFFFAOYSA-N 0.000 claims description 5
- 239000003546 flue gas Substances 0.000 claims description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 claims description 5
- 229910001415 sodium ion Inorganic materials 0.000 claims description 5
- 238000001179 sorption measurement Methods 0.000 claims description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 4
- UIIMBOGNXHQVGW-DEQYMQKBSA-M Sodium bicarbonate-14C Chemical group [Na+].O[14C]([O-])=O UIIMBOGNXHQVGW-DEQYMQKBSA-M 0.000 claims description 4
- 229910052799 carbon Inorganic materials 0.000 claims description 4
- 239000000571 coke Substances 0.000 claims description 4
- 239000000463 material Substances 0.000 claims description 4
- 238000000746 purification Methods 0.000 claims description 4
- 235000017557 sodium bicarbonate Nutrition 0.000 claims description 4
- 229910000030 sodium bicarbonate Inorganic materials 0.000 claims description 4
- 239000003610 charcoal Substances 0.000 claims description 3
- 238000005194 fractionation Methods 0.000 claims description 3
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 claims description 3
- 239000007795 chemical reaction product Substances 0.000 claims description 2
- 238000000926 separation method Methods 0.000 abstract description 9
- 238000007254 oxidation reaction Methods 0.000 abstract description 7
- 238000005516 engineering process Methods 0.000 abstract description 6
- 230000003647 oxidation Effects 0.000 abstract description 6
- 238000000354 decomposition reaction Methods 0.000 abstract description 5
- LELOWRISYMNNSU-UHFFFAOYSA-N hydrogen cyanide Chemical compound N#C LELOWRISYMNNSU-UHFFFAOYSA-N 0.000 abstract description 5
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 abstract description 4
- 229910000037 hydrogen sulfide Inorganic materials 0.000 abstract description 4
- 239000003034 coal gas Substances 0.000 abstract description 2
- JGIATAMCQXIDNZ-UHFFFAOYSA-N calcium sulfide Chemical compound [Ca]=S JGIATAMCQXIDNZ-UHFFFAOYSA-N 0.000 abstract 1
- HYHCSLBZRBJJCH-UHFFFAOYSA-N sodium polysulfide Chemical compound [Na+].S HYHCSLBZRBJJCH-UHFFFAOYSA-N 0.000 abstract 1
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 abstract 1
- 235000019345 sodium thiosulphate Nutrition 0.000 abstract 1
- 239000000047 product Substances 0.000 description 12
- 230000015556 catabolic process Effects 0.000 description 6
- 230000008025 crystallization Effects 0.000 description 6
- 238000006731 degradation reaction Methods 0.000 description 6
- 150000003839 salts Chemical class 0.000 description 6
- 150000001875 compounds Chemical class 0.000 description 4
- 239000005864 Sulphur Substances 0.000 description 3
- 239000012467 final product Substances 0.000 description 3
- 229910052717 sulfur Inorganic materials 0.000 description 3
- 239000011593 sulfur Substances 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 238000004061 bleaching Methods 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 239000002826 coolant Substances 0.000 description 2
- 230000008014 freezing Effects 0.000 description 2
- 238000007710 freezing Methods 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000007086 side reaction Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid group Chemical group S(O)(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- WJEIYVAPNMUNIU-UHFFFAOYSA-N [Na].OC(O)=O Chemical compound [Na].OC(O)=O WJEIYVAPNMUNIU-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical group N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 description 1
- 229910052921 ammonium sulfate Inorganic materials 0.000 description 1
- 235000011130 ammonium sulphate Nutrition 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 239000012295 chemical reaction liquid Substances 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 238000009841 combustion method Methods 0.000 description 1
- 235000009508 confectionery Nutrition 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 239000012065 filter cake Substances 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 229910003480 inorganic solid Inorganic materials 0.000 description 1
- 239000010808 liquid waste Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 238000012946 outsourcing Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 230000020477 pH reduction Effects 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 239000013049 sediment Substances 0.000 description 1
- -1 simultaneously Chemical compound 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000002594 sorbent Substances 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 238000001149 thermolysis Methods 0.000 description 1
- 238000007738 vacuum evaporation Methods 0.000 description 1
- 238000009279 wet oxidation reaction Methods 0.000 description 1
Landscapes
- Removal Of Specific Substances (AREA)
- Treating Waste Gases (AREA)
Abstract
The invention discloses a method for treating a sodium-alkali desulfurization waste liquid by adopting a causticization-acidification method, which belongs to the field of desulfurization waste liquid treatment technology. The method comprises the steps of waste liquid pretreatment to remove impurity, decomposition and decoloring by heating, oxidization causticization-separation, acidification-separation, evaporation for concentration, and cooling crystallization-separation. The method provided by the invention is used for treating desulfurization waste liquids produced by sodium-alkali method for removing hydrogen sulfide and hydrogen cyanide in coal gas or other gases, can transform sodium thiosulfate, sodium polysulfide and sodium sulfate in the sodium-alkali desulfurization waste liquid to calcium sulfite, calcium sulfide and calcium sulfate precipitates through heating decomposition, oxidation, and causticization, and can extract high-purity sodium carbonate and sodium thiocyanate; the recycled sodium alkali can return the desulfurization system circulation to reduce alkali consumption of the desulfurization operation.
Description
Technical field:
The invention belongs to field of desulfurization waste liquid treatment technology, be specifically related to the method for a kind of causticization-acidization process sodium alkali desulfurization waste liquor.
Background technology:
In the chemical fields such as Coal Chemical Industry, petrochemical complex and Sweet natural gas, gas adopts Wet Catalytic Oxidation Method technique to remove hydrogen sulfide, the feature of its technique is that the hydrogen sulfide of absorption is catalytically converted into sulfur foam, separate out the water of equimolecular number, there is element or the compounds such as prussic acid, oxygen, sulphur, alkali due to system simultaneously, therefore the side reaction generating salt occurs simultaneously.With sodium carbonate as the secondary salt generated during alkali source mainly Sodium Thiocyanate 99, Sulfothiorine, sodium polysulphide, sodium sulfate etc., the accumulation of side reaction salt makes the receptivity of doctor solution decline, therefore outer row's part the doctor solution (being commonly called as desulfurization waste liquor) of secondary salt be must contain continuously, and new doctor solution maintains doctor solution quality and sweetening power with the load alleviating secondary salt supplemented.Outer row has to pass through process containing the desulfurization waste liquor of secondary salt, and the desulfurization waste liquor contaminate environment of untreated direct discharge and water body, have strong corrosive power to hardware.The treatment process of existing sodium alkali desulfurization waste liquor is mainly as follows:
1, the method for treating waste liquid matched with modified ADA desulfurizer technique adopts substep evaporating, concentrating and crystallizing method to extract Sulfothiorine and Sodium Thiocyanate 99 coarse products, technique that the method is also called " freezing Steppecd crystallization ".The method feature first carries out vacuum evaporation, then Vacuum Heat filters except carbonic acid sodium impurity, filtrate is cooled to-5 DEG C with refrigerated water, separate out Sulfothiorine crystallization, the thick product of Sulfothiorine is extracted through centrifugation, remove the filtrate after Sulfothiorine as the raw material extracting Sodium Thiocyanate 99, extract rough Sodium Thiocyanate 99 by the same method.The method requires to adopt the refrigerated water cooling concentration liquid of-5 DEG C to make Sulfothiorine crystallization, and therefore processing unit configuration is many, needs auxiliary construction refrigerator device, long flow path, power consumption is high, and concentrated solution composition is complicated, crystallized product impurity is many, not easily primary crystallization obtain straight product.
2, Japan's " ammonia type-Taka Haake this " sulfur removal technology mainly adopts the uncommon Luo Hakesi process for treating waste liquor being called " wet oxidation process ", and final product is ammonium sulfate.And Japan's " sodium form-Taka Haake this " sulfur removal technology liquid waste disposal mainly adopts " reduction combustion method " burning spent liquor and sulphur, final product is sulfuric acid and sodium carbonate.The shortcoming of the method is that process for treating waste liquor route is long, and added value of product is not high, production equipment construction cost and maintenance cost high, so overall economic benefit is low, Sodium Thiocyanate 99 more valuable in waste liquid in addition does not reclaim.
Summary of the invention:
The present invention is directed to Problems existing in existing sodium alkali desulfurization waste liquor treatment process, the method for a kind of causticization-acidization process sodium alkali desulfurization waste liquor is provided.
The method concrete steps of one causticization provided by the present invention-acidization process sodium alkali desulfurization waste liquor are as follows:
(1) entrained solid impurity in the sorbing material such as coke or gac fractionation by adsorption sodium alkali desulfurization waste liquor at normal temperatures and pressures, is used;
(2) the sodium alkali desulfurization waste liquor after described step (1) process is through evaporation concentration, Sulfothiorine unstable in waste liquid and sodium polysulphide is made to be decomposed into S-WAT and sodium sulphite respectively, and while separating out elemental sulfur, in described sodium alkali desulfurization waste liquor, be blown into pressurized air carry out oxidizing reaction, make to become sodium sulfate through decomposing the S-WAT produced with oxidizing sodium sulphide in described sodium alkali desulfurization waste liquor, the temperature of described thermolysis-oxidizing reaction is 85 ~ 125 DEG C, the volume that described pressurized air is blown into is 20 ~ 160 times of described sodium alkali desulfurization waste liquor volume,
(3) by after the sodium alkali desulfurization waste liquor filtering and impurity removing of step (2) after thermolysis-oxidizing reaction process, in filtrate, milk of lime Ca (OH) is added
2carry out causticizing reaction, the temperature of causticizing reaction is 85 ~ 125 DEG C, makes the sodium sulfate Na in filtrate
2sO
4and remaining S-WAT Na
2sO
3with sodium sulphite Na
2s changes into calcium sulfate and calcium sulfite and sulfurated lime respectively and precipitates, and sodium ion and hydroxide ion react and generate sodium hydroxide, after calcium sulfite, sulfurated lime and calcium sulfate filtering, obtain the filtrate of being rich in Sodium Thiocyanate 99 and sodium hydroxide;
(4) filtrate of being rich in Sodium Thiocyanate 99 and sodium hydroxide that step (3) obtains is placed in acidifier, the stack gas through purification is blown in described acidifier, make the sodium hydroxide generation neutralization reaction in the carbonic acid gas in described stack gas and described filtrate of being rich in Sodium Thiocyanate 99 and sodium hydroxide, reaction product is sodium bicarbonate, the sodium bicarbonate that neutralization reaction generates and the sodium hydroxide that described step (3) causticizing reaction generates react generation sodium carbonate further, simultaneously, carbonic acid gas in described purifying flue gas and the described calcium hydroxide reaction remained in the filtrate of Sodium Thiocyanate 99 and sodium hydroxide that is rich in generate precipitation of calcium carbonate, the acidizing fluid being rich in Sodium Thiocyanate 99 and sodium carbonate is obtained after reacted filtrate mistake is filtered precipitation of calcium carbonate,
(5) acidizing fluid being rich in Sodium Thiocyanate 99 and sodium carbonate step (4) obtained puts into the first crystallisation by cooling groove after heating concentrated and charcoal absorption removing solid impurity, 35 ~ 45 DEG C are cooled to by the water at low temperature that temperature is 18 ~ 25 DEG C, separate out crystals of sodium carbonate after cool slurry, the slurries containing crystals of sodium carbonate are put into sodium carbonate centrifugal filter and filters out crystals of sodium carbonate;
(6) step (5) is filtered out the filtrate after crystals of sodium carbonate and put into the second crystallisation by cooling groove, 25 ~ 30 DEG C are cooled to by the water at low temperature that temperature is 18 ~ 25 DEG C, separate out Sodium Thiocyanate 99 crystal, slurry impouring Sodium Thiocyanate 99 centrifugal filter containing Sodium Thiocyanate 99 crystal is filtered, obtains Sodium Thiocyanate 99 crystal;
(7) filtrate filtered out after Sodium Thiocyanate 99 crystal returns desulphurization system.
The principles of chemistry involved by the inventive method are specific as follows:
First carry out heating concentration to solution, make the unstable compound decomposition such as sodium polysulphide, Sulfothiorine separate out elemental sulfur, generate S-WAT, sodium sulphite etc., the atmospheric oxidation be then blown into generates sodium sulfate.
Na
2S
2O
3 === Na
2SO
3 + S
Na
2Sx+1=== Na
2S + xS
2Na
2SO
3 + O
2=== 2Na
2SO
4
Na
2S + 2O
2=== Na
2SO
4
With milk of lime Ca (OH)
2by the sodium sulfate N in waste liquid
a2sO
4and remaining S-WAT N
a2sO
3with sodium sulphite N
a2s carries out causticizing reaction respectively and changes into calcium sulfate and calcium sulfite and sulfurated lime precipitation, and sodium ion and hydroxide ion react and generate sodium hydroxide, after calcium sulfite, sulfurated lime and calcium sulfate filtering, obtain the filtrate of being rich in Sodium Thiocyanate 99 and sodium hydroxide.
Na
2SO
3+Ca(OH)
2== CaSO
3 ↓+ 2NaOH
Na
2SO
4 +Ca(OH)
2 == CaSO
4↓
+ 2NaOH
Na
2S + Ca(OH)
2 === CaS↓+ 2NaOH
Because Sodium Thiocyanate 99 and calcium hydroxide do not react, so only deposit sodium hydroxide and Sodium Thiocyanate 99 and a small amount of superfluous calcium hydroxide in solution after sediment separate out.Then the filtrate after filtering precipitate is placed in acidifier, and the stack gas be blown in acidifier through purification, make the carbonic acid gas in stack gas and the sodium hydroxide generation neutralization reaction be rich in Sodium Thiocyanate 99 and sodium hydroxide filtrate, generate sodium bicarbonate, there is causticizing reaction further and generate sodium carbonate in sodium bicarbonate and carbonic acid gas, simultaneously, calcium hydroxide reaction residual in carbonic acid gas in purifying flue gas and filtrate generates precipitation of calcium carbonate, obtains the acidizing fluid being rich in Sodium Thiocyanate 99 and sodium carbonate after reacted filtrate mistake is filtered precipitation of calcium carbonate.
CO
2 + Ca(OH)
2 == CaCO
3 ↓ + H
2O
CO
2 + NaOH == NaHCO
3
NaHCO
3+ NaOH == Na
2CO
3 +H
2O
To the acidizing fluid of Sodium Thiocyanate 99 and sodium carbonate be rich in through heating concentrated and charcoal absorption removing solid impurity.
Because the dissolubility difference of sodium carbonate and Sodium Thiocyanate 99 two kinds of compound crystals is larger, crystallisation by cooling method can be adopted successively to extract sodium carbonate and Sodium Thiocyanate 99 crystal product respectively, sodium carbonate returns to desulphurization circulating liquid system, and Sodium Thiocyanate 99 crystal is as the finished product export trade.
The inventive method comprises following process links: the decolouring of waste liquid pretreatment impurity removing, thermal degradation, oxidation causticization-separation, acidifying-separation, evaporation concentration, crystallisation by cooling-separation.
" waste liquid pretreatment process " removes the organic or inorganic solid impurity entered at random in waste liquid, as sulphur, tar, ferruginization compound.
" thermal degradation bleaching process " is that thermolysis Sulfothiorine and sodium polysulphide separate out elemental sulfur and S-WAT and sodium sulphite, and removes catalyst residue, and solution is become colorless.
" oxidation causticization-separation circuit " is, with air, the S-WAT that " thermal degradation bleaching process " generates is become sodium sulfate with oxidizing sodium sulphide; With milk of lime Ca (OH)
2with sodium sulfate N
a2sO
4and remaining S-WAT N
a2sO
3with sodium sulphite N
a2s carries out causticizing reaction generation calcium sulfate and calcium sulfite and sulfurated lime respectively and precipitates; Sodium ion in solution and hydroxide ion react and generate sodium hydroxide; After calcium sulfite, sulfurated lime and calcium sulfate filtering, obtain the filtrate of being rich in Sodium Thiocyanate 99 and sodium hydroxide.
" acidifying-separation circuit " utilizes the filtrate after being separated with causticizing reaction in the carbonic acid gas in stack gas, sodium hydroxide is made to generate sodium bicarbonate, sodium bicarbonate reacts with sodium hydroxide further and generates sodium carbonate, meanwhile, by the excess calcium hydroxide that remains in filtrate and generate precipitation of calcium carbonate; The acidizing fluid being rich in Sodium Thiocyanate 99 and sodium carbonate is obtained after reacted filtrate mistake is filtered precipitation of calcium carbonate.
" evaporation concentration operation " by removing calcium carbonate after, be rich in Sodium Thiocyanate 99 and sodium carbonate acidizing fluid concentration and evaporation reduce moisture.
" crystallisation by cooling-separation circuit " is the dissolubility difference according to sodium carbonate and Sodium Thiocyanate 99, and concentrated solution is cooled to relevant temperature, and substep separates out crystals of sodium carbonate and Sodium Thiocyanate 99 crystal.
The inventive method is compared with " the freezing Steppecd crystallization " of background technology introduction, and have the advantage that device is simple, operational path is shorter, and save refrigerator system, process cost is low, and process cost is existing methods 35% to 40%.Industrial electro depletion few 75% to 80%, reclaims sodium carbonate 80% to 85%, makes the sodium carbonate outsourcing amount in sweetening process directly reduce 65% to 70% from waste liquid.Existing method needs are chilled to the refrigerated water of less than-5 DEG C as crystallization water coolant in addition, and Sulfothiorine and the Sodium Thiocyanate 99 product purity of extraction are low, and can not make up the sodium carbonate alkali source of desulphurization system needs.
The desulfurization waste liquor that the inventive method removes hydrogen sulfide in coal gas or other gas for the treatment of sodium alkali, HCN produces, the method can under normal temperature condition, by thermal degradation, oxidation, causticization, the Sulfothiorine in sodium alkali desulfurization waste liquor, sodium polysulphide, sodium sulfate are changed into calcium sulfite, sulfurated lime and calcium sulfate precipitation, extract highly purified sodium carbonate and Sodium Thiocyanate 99 simultaneously, reclaim soda and return to desulphurization system circulation, reduce the alkaline consumption of desulfurization operations.
Accompanying drawing illustrates:
Fig. 1 the inventive method process flow diagram.
In figure: 1-strainer, 2-thermal degradation device, 3-causticizer, 4-carbonic acid gas acidifier, 5-heats concentration kettle, 6-first crystallisation by cooling groove, 7-second crystallisation by cooling groove, 8-first strainer, 9-second strainer, 10-the 3rd strainer, 11-the 4th strainer, 12-sodium carbonate whizzer, 13-Sodium Thiocyanate 99 whizzer, 14-acidifying liquid bath, 15-filtrate medial launder, A-stock liquid, B-calcium sulfate, C-crystallize sodium carbonate filter cake, D-Sodium Thiocyanate 99, the new gac of E-, F-pressurized air, G-decompose slag, H-calcium carbonate, I-milk of lime, J-purifying flue gas, K-carries filtrate after Sodium Thiocyanate 99, S-steam, W-water coolant, P-waste active carbon.
Embodiment:
First sodium alkali desulfurization waste liquor and stock liquid A are put into strainer 1 by the inventive method, the built-in coke of strainer 1 or gac or other sorbing material, stock liquid A is by entrained solid impurity in fractionation by adsorption waste liquid after coke or active carbon adsorption material at normal temperatures and pressures, strainer can operate continuously very several months several weeks, when absorption reaches capacity or resistance increases by recoil or change sorbent material and keep adsorber working properly.
Stock liquid A after rough purification is sent into thermal degradation device 2, heat with steam S, the decomposition of components such as Sulfothiorine, sodium polysulphide is made to be S-WAT and sodium sulphite, and separate out elemental sulfur and evaporate portion of water, be blown into the S-WAT and sodium sulphite that generate in pressurized air F oxidic raw materials liquid A simultaneously, convert it into sodium sulfate.Oxidizing reaction service temperature controls within the scope of 85 ~ 125 DEG C.When heating, the decomposition of components such as Sulfothiorine, sodium polysulphide is S-WAT and sodium sulphite, and separates out elemental sulfur.
Reaction solution after thermolysis-oxidizing reaction is put into the first strainer 8 elimination impurity G, filtrate sends into causticizer 3, adds milk of lime I and carries out causticizing reaction, make sodium sulfate and remaining S-WAT N
a2sO
3with sodium sulphite N
a2s changes into calcium sulfate and calcium sulfite and sulfurated lime respectively and precipitates, and sodium ion and hydroxide ion react and generate sodium hydroxide, and causticizing reaction temperature is within the scope of 85 ~ 125 DEG C.Causticizing reaction liquid is sent into the second strainer 9 and is leached calcium sulfate and calcium sulfite and sulfurated lime B, enrichment Sodium Thiocyanate 99 and sodium hydroxide in filtrate, filtrate moves into carbonic acid gas acidifier 4, be blown into purifying flue gas J simultaneously, the neutralization reaction of carbonic acid gas and sodium hydroxide occurs in acidifier, and reaction final product is sodium carbonate.Acidification reaction removes calcium hydroxide superfluous in filtrate simultaneously and generates precipitation of calcium carbonate and solution separating.Acidizing fluid is crossed through the 3rd strainer 10 and is filtered precipitation of calcium carbonate H.Filtrate collection is to acidifying liquid bath 14.Sodium Thiocyanate 99 and sodium carbonate is enriched, as the stock liquid extracting product Sodium Thiocyanate 99 and recovery sodium carbonate in acidizing fluid.So far the pre-treatment of stock liquid terminates.Acidizing fluid is moved into heating concentration kettle 5, solution heats concentrated in still, and adds the residual solid impurity in the solution of new gac E absorption, makes solution more colourless clean.Concentrated solution is put into the 4th strainer 11 by concentrated end, crosses and filters impurity and take out waste active carbon P.Concentrated solution is put into the first crystallisation by cooling groove 6 water at low temperature (18 ~ 25 DEG C) is cooled to specified temperature (35 ~ 45 DEG C) later, and cool slurry separates out crystals of sodium carbonate, slurries is put into sodium carbonate centrifugal filter 12, filters out crystallize sodium carbonate thing C.And then filtrate is put into the second crystallisation by cooling groove 7 water at low temperature (18 ~ 25 DEG C) be cooled to specified temperature (25 ~ 30 DEG C), separate out object product Sodium Thiocyanate 99 crystal, slurry impouring Sodium Thiocyanate 99 whizzer 13 is filtered, take out crystalline product Sodium Thiocyanate 99 D product, filtrate collection is to filtrate medial launder 15.This is the final filtrate of the inventive method, and not containing Sulfates, only containing a small amount of sodium carbonate and Sodium Thiocyanate 99, this kind of filtrate K returns desulphurization circulating liquid system.Also return to desulfurization workshop section as desulfurization alkali from the isolated sodium carbonate of sodium carbonate centrifugal filter, regeneration sodium carbonate can the new alkali of Some substitute.
Claims (1)
1., by a method for causticization-acidization process sodium alkali desulfurization waste liquor, it is characterized in that the method concrete steps are as follows:
(1) at normal temperatures and pressures, entrained solid impurity in coke or active carbon adsorption material fractionation by adsorption sodium alkali desulfurization waste liquor is used;
(2) the sodium alkali desulfurization waste liquor after described step (1) process is through evaporation concentration, Sulfothiorine unstable in waste liquid and sodium polysulphide is made to be decomposed into S-WAT and sodium sulphite respectively, and while separating out elemental sulfur, in described sodium alkali desulfurization waste liquor, be blown into pressurized air carry out oxidizing reaction, make to become sodium sulfate through decomposing the S-WAT produced with oxidizing sodium sulphide in described sodium alkali desulfurization waste liquor, the temperature of described thermolysis-oxidizing reaction is 85 ~ 125 DEG C, the volume that described pressurized air is blown into is 20 ~ 160 times of described sodium alkali desulfurization waste liquor volume,
(3) by after the sodium alkali desulfurization waste liquor filtering and impurity removing of step (2) after thermolysis-oxidizing reaction process, in filtrate, milk of lime Ca (OH) is added
2carry out causticizing reaction, the temperature of causticizing reaction is 85 ~ 125 DEG C, makes the sodium sulfate Na in filtrate
2sO
4and remaining S-WAT Na
2sO
3with sodium sulphite Na
2s changes into calcium sulfate and calcium sulfite and sulfurated lime respectively and precipitates, and sodium ion and hydroxide ion react and generate sodium hydroxide, after calcium sulfite, sulfurated lime and calcium sulfate filtering, obtain the filtrate of being rich in Sodium Thiocyanate 99 and sodium hydroxide;
(4) filtrate of being rich in Sodium Thiocyanate 99 and sodium hydroxide that step (3) obtains is placed in acidifier, the stack gas through purification is blown in described acidifier, make the sodium hydroxide generation neutralization reaction in the carbonic acid gas in described stack gas and described filtrate of being rich in Sodium Thiocyanate 99 and sodium hydroxide, reaction product is sodium bicarbonate, the sodium bicarbonate that neutralization reaction generates and the sodium hydroxide that described step (3) causticizing reaction generates react generation sodium carbonate further, simultaneously, carbonic acid gas in described purifying flue gas and the described calcium hydroxide reaction remained in the filtrate of Sodium Thiocyanate 99 and sodium hydroxide that is rich in generate precipitation of calcium carbonate, the acidizing fluid being rich in Sodium Thiocyanate 99 and sodium carbonate is obtained after reacted filtrate mistake is filtered precipitation of calcium carbonate,
(5) acidizing fluid being rich in Sodium Thiocyanate 99 and sodium carbonate step (4) obtained puts into the first crystallisation by cooling groove after heating concentrated and charcoal absorption removing solid impurity, 35 ~ 45 DEG C are cooled to by the water at low temperature that temperature is 18 ~ 25 DEG C, separate out crystals of sodium carbonate after cool slurry, the slurries containing crystals of sodium carbonate are put into sodium carbonate centrifugal filter and filters out crystals of sodium carbonate;
(6) step (5) is filtered out the filtrate after crystals of sodium carbonate and put into the second crystallisation by cooling groove, 25 ~ 30 DEG C are cooled to by the water at low temperature that temperature is 18 ~ 25 DEG C, separate out Sodium Thiocyanate 99 crystal, slurry impouring Sodium Thiocyanate 99 centrifugal filter containing Sodium Thiocyanate 99 crystal is filtered, obtains Sodium Thiocyanate 99 crystal;
(7) filtrate filtered out after Sodium Thiocyanate 99 crystal returns desulphurization system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310609080.6A CN103588340B (en) | 2013-11-27 | 2013-11-27 | Method for treating sodium-alkali desulfurization waste liquid by causticization-acidification method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310609080.6A CN103588340B (en) | 2013-11-27 | 2013-11-27 | Method for treating sodium-alkali desulfurization waste liquid by causticization-acidification method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103588340A CN103588340A (en) | 2014-02-19 |
| CN103588340B true CN103588340B (en) | 2014-12-24 |
Family
ID=50078706
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310609080.6A Expired - Fee Related CN103588340B (en) | 2013-11-27 | 2013-11-27 | Method for treating sodium-alkali desulfurization waste liquid by causticization-acidification method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103588340B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111484211A (en) * | 2020-06-09 | 2020-08-04 | 河南东泰制药有限公司 | 2,6-Dichlorodiphenylamine production high-concentration alkaline waste liquid treatment method and device |
| CN112340911A (en) * | 2020-09-29 | 2021-02-09 | 陕西陕焦化工有限公司 | Method for recycling desulfurization waste liquid |
| CN112499813A (en) * | 2020-11-20 | 2021-03-16 | 成都千砺金科技创新有限公司 | Production method for full resource recycling of waste water in titanium dioxide production by sulfuric acid process |
| CN113292191B (en) * | 2021-05-31 | 2025-02-14 | 陕西延长中煤榆林能源化工股份有限公司 | A device for catalytic thermal cracking of residual oil and resource utilization of waste alkali liquid from coal to olefins |
| CN115090096A (en) * | 2022-06-06 | 2022-09-23 | 武汉天源环保股份有限公司 | Landfill leachate deodorization method and system |
| CN115784482A (en) * | 2022-09-07 | 2023-03-14 | 浙江伽能环境工程有限责任公司 | A method for oxygen pressure treatment of waste liquid containing sodium polysulfide |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5362458A (en) * | 1993-03-22 | 1994-11-08 | General Electric Environmental Services, Incorporated | Process for the simultaneous absorption of sulfur oxides and production of ammonium sulfate |
| CN101543729A (en) * | 2009-03-25 | 2009-09-30 | 南京东大苏威能源环保工程有限公司 | Method suitable for utilization of resource of sintering flue gas desulphurization waste solution |
| CN101597522A (en) * | 2009-06-29 | 2009-12-09 | 朱春阳 | A kind of desulfuration processing method of coke oven gas and isolated plant thereof |
| CN101985359A (en) * | 2009-07-29 | 2011-03-16 | 中国科学院过程工程研究所 | Method for preparing thiocyanate and sulfate by utilizing desulfuration waste liquor in coking plant |
| CN102161541A (en) * | 2011-01-24 | 2011-08-24 | 江苏中显集团有限公司 | Method for extracting salt from coking desulphurization waste solution and special device thereof |
| CN102259896A (en) * | 2011-06-21 | 2011-11-30 | 安徽工业大学 | Method for extracting sodium thiocyanate from coking desulfurization waste liquid |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5722115A (en) * | 1980-07-16 | 1982-02-05 | Sumikin Coke Co Ltd | Treating method of crude ammonium sulfate |
| JPH07265870A (en) * | 1994-03-31 | 1995-10-17 | Kansai Electric Power Co Inc:The | Method for treating water containing dithionate ion |
-
2013
- 2013-11-27 CN CN201310609080.6A patent/CN103588340B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5362458A (en) * | 1993-03-22 | 1994-11-08 | General Electric Environmental Services, Incorporated | Process for the simultaneous absorption of sulfur oxides and production of ammonium sulfate |
| CN101543729A (en) * | 2009-03-25 | 2009-09-30 | 南京东大苏威能源环保工程有限公司 | Method suitable for utilization of resource of sintering flue gas desulphurization waste solution |
| CN101597522A (en) * | 2009-06-29 | 2009-12-09 | 朱春阳 | A kind of desulfuration processing method of coke oven gas and isolated plant thereof |
| CN101985359A (en) * | 2009-07-29 | 2011-03-16 | 中国科学院过程工程研究所 | Method for preparing thiocyanate and sulfate by utilizing desulfuration waste liquor in coking plant |
| CN102161541A (en) * | 2011-01-24 | 2011-08-24 | 江苏中显集团有限公司 | Method for extracting salt from coking desulphurization waste solution and special device thereof |
| CN102259896A (en) * | 2011-06-21 | 2011-11-30 | 安徽工业大学 | Method for extracting sodium thiocyanate from coking desulfurization waste liquid |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103588340A (en) | 2014-02-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103588340B (en) | Method for treating sodium-alkali desulfurization waste liquid by causticization-acidification method | |
| US7258848B1 (en) | Process for scrubbing ammonia from acid gases comprising ammonia and hydrogen sulfide | |
| CN103601219A (en) | Method for extracting sodium carbonate and sodium thiocyanate from sodium alkali desulfurization liquid waste by using causticization-acidification method | |
| CN112553647A (en) | Method for producing lithium hydroxide monohydrate from brine | |
| CN103011201B (en) | Method for extracting ammonium thiocyanate from ammonia-process desulfurization waste liquid by oxidation process | |
| CN103030207B (en) | Method for treating ammonia desulfurization waste liquid by oxidation method | |
| CN102225816A (en) | Method for recovering secondary salts from desulfurization liquid and recycling desulfurization liquid | |
| US3971844A (en) | Method for removing sodium sulfate from aqueous solutions | |
| CN102020369A (en) | Desulfuration waste water treatment process | |
| CA2431403C (en) | Process for recovering arsenic from acidic aqueous solution | |
| US4044101A (en) | Method of treating exhaust gases containing nitrogen oxides and sulfurous acid gas | |
| CN102225798A (en) | A method for comprehensive utilization of desulfurization waste liquid | |
| CN102336417B (en) | Method for recovering sodium sulfocyanate from desulfurized and decyanated wastewater of coke-oven gas | |
| KR102230898B1 (en) | METHOD OF TREATING TAIL GAS AND METHOD OF Manufacturing SODIUM bICARBONATE THEREFROM | |
| US4310691A (en) | Method for selectively recovering sodium citrate from an aqueous solution | |
| CN110844926A (en) | Production method of high-purity magnesium sulfite | |
| CN107970744B (en) | Method for simultaneously recovering sulfur dioxide and zinc sulfate by combined desulfurization of aluminum sulfate/zinc oxide | |
| CN104709884A (en) | System capable of selectively producing sodium sulfide or sodium hydrosulfide | |
| CN109534542A (en) | The method of fume desulfurizing agent purified treatment | |
| CN102351345B (en) | Method for recovering melamine from melamine waste water and co-producing desulfurizer | |
| WO2012050437A2 (en) | Production of sodium bicarbonate from a basic process stream | |
| SU1303040A3 (en) | Method for extracting chemicals from green lye containing chlorides | |
| US4177244A (en) | Process for purge stream treatment in removal of sulfur dioxide | |
| CN101760642B (en) | Process for recovering magnesium from magnesium sulfate solution | |
| CN104449881A (en) | Method for purifying coke oven gas of vacuum carbonate-process desulphurization and recovering sodium thiocyanate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20141224 Termination date: 20151127 |