CN103342433A - Method for recovering acid and alkali from viscose sodium sulfate waste liquor through bipolar membrane electrodialysis way - Google Patents
Method for recovering acid and alkali from viscose sodium sulfate waste liquor through bipolar membrane electrodialysis way Download PDFInfo
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- CN103342433A CN103342433A CN2013103120369A CN201310312036A CN103342433A CN 103342433 A CN103342433 A CN 103342433A CN 2013103120369 A CN2013103120369 A CN 2013103120369A CN 201310312036 A CN201310312036 A CN 201310312036A CN 103342433 A CN103342433 A CN 103342433A
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- 239000012528 membrane Substances 0.000 title claims abstract description 172
- 238000000034 method Methods 0.000 title claims abstract description 121
- 238000000909 electrodialysis Methods 0.000 title claims abstract description 108
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 title claims abstract description 79
- 229910052938 sodium sulfate Inorganic materials 0.000 title claims abstract description 72
- 235000011152 sodium sulphate Nutrition 0.000 title claims abstract description 72
- 229920000297 Rayon Polymers 0.000 title claims abstract description 65
- 239000002253 acid Substances 0.000 title claims abstract description 48
- 239000002699 waste material Substances 0.000 title claims abstract description 45
- 239000003513 alkali Substances 0.000 title abstract description 40
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 152
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- 239000000126 substance Substances 0.000 claims abstract description 39
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- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 claims abstract description 23
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- 239000012535 impurity Substances 0.000 claims abstract description 16
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- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 68
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- OMPJBNCRMGITSC-UHFFFAOYSA-N Benzoylperoxide Chemical compound C=1C=CC=CC=1C(=O)OOC(=O)C1=CC=CC=C1 OMPJBNCRMGITSC-UHFFFAOYSA-N 0.000 description 4
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 4
- 235000001018 Hibiscus sabdariffa Nutrition 0.000 description 4
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- 239000011734 sodium Substances 0.000 description 2
- 229940056729 sodium sulfate anhydrous Drugs 0.000 description 2
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- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- 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 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- DPDMMXDBJGCCQC-UHFFFAOYSA-N [Na].[Cl] Chemical compound [Na].[Cl] DPDMMXDBJGCCQC-UHFFFAOYSA-N 0.000 description 1
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- GPRLSGONYQIRFK-UHFFFAOYSA-N hydron Chemical compound [H+] GPRLSGONYQIRFK-UHFFFAOYSA-N 0.000 description 1
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- 239000011701 zinc Substances 0.000 description 1
Landscapes
- Separation Using Semi-Permeable Membranes (AREA)
- Water Treatment By Electricity Or Magnetism (AREA)
Abstract
The invention discloses a method for recovering acid and alkali from viscose sodium sulfate waste liquor through a bipolar membrane electrodialysis way. The method is characterized by sequentially comprising the following steps of: crystallizing; adjusting pH (Potential of Hydrogen); initially filtering at the first time; oxidizing reducing substances through O3; initially filtering at the second time; removing organic substances through activated carbon; removing zinc ions through ion exchange resin; filtering and performing refined filtration through pp micropores; preparing acid and alkali; and concentrating. By adopting the method, the regenerative recovery rate of the acid and alkali in the viscose sodium sulfate waste liquor is increased, and the damage of impurities in the waste liquor to a bipolar membrane is reduced, so that the service life of the bipolar membrane is prolonged, and the bipolar membrane electrodialysis and subsequent processes can be able to be carried out smoothly; in addition, sodium hydroxide crystals of which the alkali concentration is controlled to 96%, 98% and 99% can be obtained, which can be directly marketed, thus the benefit is brought.
Description
Technical field
The present invention relates to the method that material is handled in a kind of Chemical Manufacture, more particularly, the present invention relates to a kind of viscose fiber sodium sulfate waste liquid and adopt the bipolar membrane electrodialysis method to reclaim the method for soda acid, belong to the viscose fiber production technical field.
Background technology
Viscose glue and acid coagulating bath effect are neutralized alkali in the viscose fiber moulding process in chemical fibre industry, and sodium cellulose xanghate is decomposed and the regeneration cellulose hydrate, the cellulose sulfonate in this process in the viscose glue, free NaOH and the Na that generates because of side reaction
2CS
3, side reaction product such as polysulfide all can with precipitation bath in sulfuric acid reaction generate sodium sulfate.Comprise the acid bath operation that consumes sulfuric acid in the viscose fiber production, comprise that also the sheet steeping operation, soda cellulose sulphonate dissolution process, the waste gas that consume sodium hydroxide absorb operation, concise operation and the sour water neutralizing treatment operation of compressing and washing.
In the precipitation bath the main effect of sodium sulfate be impel viscose stream to solidify and suppress sulfolysis from, the reproduction speed of cellulose sulfonate is delayed, improve the concentration of sodium sulfate in the precipitation bath, spinning operation is easier to, tow is difficult for broken end, and can reduce the dissociation degree of sulfuric acid, make tow when leaving precipitation bath, still have certain residue gamma value, but the sodium sulfate in the precipitation bath is also unsuitable too high, otherwise fiber is solidified overruns, can not form microtexture, and generate thick crystalline particle, the ectonexine of fiber is heterogeneity also.
In spinning process, sodium sulphate content in the precipitation bath constantly increases makes it can't satisfy the requirement of technology, if only by adding the raw material that is consumed in the precipitation bath to replenish its concentration recycling and will make the total amount of precipitation bath increase and can't store, can only be at regular time and quantity with the precipitation bath discharging, acid wherein, salt, metal ion etc. will cause that serious environmental pollutes, brings huge pressure and cause the huge waste of resource to sewage disposal.And sodium sulfate unnecessary in the acid bath is carried out high temperature crystallization, isolate sodium sulfate crystal, make the content of the sodium sulfate in the acid bath meet processing requirement, the acid that do not need to drain every day comes the balance acid bath, directly continue to use for spinning workshop by reinforced back, can reduce acid discharge, the output Sodium sulfate anhydrous.min(99), reduce environmental protection pressure, but make it can not produce economic benefit because impure many, the own added values of Sodium sulfate anhydrous.min(99) that the sodium sulfate high temperature crystallization is produced in the precipitation bath are low, a large amount of solid salts can't be handled, and has still brought certain pressure to environmental protection.
Bipolar Membrane is a kind of novel ion-exchange composite membranes, and it is composited by cationic exchange layer (N type film), interface hydrophilic layer (Catalytic Layer) and anionresin layer (P type film) usually, is reaction film truly.Under the DC electric field effect, Bipolar Membrane can obtain hydrogen ion and hydroxide ion respectively in the film both sides with hydrolytic dissociation.Utilize this characteristics, the bipolar membrane electrodialysis system with Bipolar Membrane and other anion and cation exchange membranes are combined into can be converted into corresponding bronsted lowry acids and bases bronsted lowry with the salt in the aqueous solution under the situation of not introducing new component, and this technology is called the bipolar membrane electrodialysis technology.Compare outstanding technical superiority such as that the bipolar membrane electrodialysis technology has is energy-efficient, environmental friendliness, simple operation with traditional technology.In recent years, bipolar membrane electrodialysis technology technology has all obtained fast development in research and aspect using two, membrane preparation technology and operation parameter optimization are constantly obtained new progress, range of application from the albumen of the desalination of chemical field and soda acid preparation, biological field and amino acid purify the purifying that is extended to trade effluent the environmental protection field, concentrate, field such as high purity water preparation, renovating, developing in cleaner production and the recycling economy process and playing the part of the role who becomes more and more important in traditional chemical separating technology.
The research report of relevant Bipolar Membrane just occurred from 50 mid-nineties 90s of 20th century, its evolution can be divided into three phases: 50 initial stages age mid-nineties 90 to 80 of 20th century of fs, this is that Bipolar Membrane develops period very slowly, Bipolar Membrane only is directly to be suppressed by two anion and cation exchange membranes, poor performance, the theoretical pressure drop of water decomposition voltage ratio is high tens times, and applied research also is in the laboratory stage based on water decomposition; Subordinate phase is from the 80's of 20th century first arrivals beginning of the nineties, because the monolithic type Bipolar Membrane has successfully been developed in the improvement of Bipolar Membrane technology of preparing, its performance improves greatly, obtained successful Application in relieving haperacidity alkali and desulfurization technology, the commodity Bipolar Membrane has appearred in this stage.At the beginning of the 90's of 20th century so far, it is the period that Bipolar Membrane develops rapidly, along with the further investigation to Bipolar Membrane working process mechanism, carried out significant improvement from membrane structure, mould material and preparation process, the performance of Bipolar Membrane is greatly improved, it wherein mainly is the improvement to cavity block and anode membrane contact interface, " monolithic type " structure that begins to occur at the beginning of from initial simple " pressure stratotype " or " coating type " structure to the 80's of 20th century, the complex construction of " Catalytic Layer " greatly reduces membrane voltage in the middle of occurring again subsequently having.
At present, the bipolar membrane electrodialysis technology has been brought into play original effect in optimizing traditional industry process and new commercial run.Its appearance has changed traditional industry and has separated and preparation process, for the technical barrier that solves in the fields such as environment, chemical industry, biology, marine chemical industry is brought new vigor and vitality into, provide effective means for solving problems such as environment that the mankind face, resource, the energy simultaneously.
It is CN102167293A that State Intellectual Property Office discloses a publication number in 2011.3.10, name is called the patent of invention of " a kind of method of using the bipolar membrane electrodialysis device to produce sulfuric acid and sodium hydroxide ", a kind of method of using the bipolar membrane electrodialysis device to produce sulfuric acid and sodium hydroxide is disclosed, this method is that metabisulfite solution is injected in the compartment of negatively charged ion selective membrane and cation selective membrane formation, water is injected into Bipolar Membrane and negatively charged ion selective membrane, in the compartment that cation selective membrane forms, under the effect of DC electric field power, in the compartment that compartment that cation selective membrane and Bipolar Membrane form towards the negatively charged ion selection face of anode and/or cation selective membrane and negative electrode form, obtain sodium hydroxide, in the compartment of the compartment of the cation selective face formation of negative electrode and/or negatively charged ion selective membrane and anode formation, obtain sulfuric acid in negatively charged ion selective membrane and Bipolar Membrane.The method that the present invention adopts can re-use the sodium sulfate waste liquid, produce can second stage employ sulfuric acid and sodium hydroxide, it is turned waste into wealth, have remarkable economic efficiency and environmental benefit.
Though above-mentioned patent can accomplish to dispose waste liquid; make acid-alkali regeneration; environment has been played the certain protection effect; but still exist the soda acid rate of recovery not high; energy consumption is big, can't online recovery and recycle, and because the pre-treatment step before entering film device not; can cause runner obstruction, membrane resistance increase, regenerating acid alkali ability in the film device to reduce, and service life of equipment is short.
It is CN102107972A that State Intellectual Property Office discloses a publication number in 2010.12.1, name is called the patent of invention of " a kind of Bipolar Membrane is to reverse osmosis method sea water desaltination pretreatment process ", disclose a kind of chemical treatment method, specifically referred to a kind of to the preceding pretreatment process in the desalting process.The present invention puts into the Bipolar Membrane device to seawater, and Bipolar Membrane wherein is a divalence separatory membrane; Utmost point liquid is sodium-chlor or the metabisulfite solution of mass concentration 1-10%; Then the alkali lye in the Bipolar Membrane device alkali chamber is mixed with water inlet, the micro-filtrate membrane filtration of the water inlet after the above-mentioned alkalization with the 0.1-0.5 micron, and then regulate pH with the acid solution of bipolar acid chamber, and regulate the pH value to 8.2-8.8, namely can be used as sea water desaltination and handle and use.Advantage of the present invention is that less investment, running cost boron content low, easy to operate, that produce water meets drinking water standard, can carry out Bipolar Membrane sea water desaltination product water hardening and tempering method and technology that heavy construction is used, solves the technical bottleneck of sea water desaltination development.The present invention can be widely used in the sea water desaltination occasion.The content of this patent disclosure is not suitable for the sodium sulfate liquid waste disposal that produces in the viscose glue production process that contains complicated ingredient impurity.
Summary of the invention
The present invention is intended to solve the waste liquid that existing application produces and reclaims problem and the defective that the soda acid technology exists through the bipolar membrane electrodialysis method in viscose fiber strand moulding process, provide a kind of viscose fiber sodium sulfate waste liquid to adopt the bipolar membrane electrodialysis method to reclaim the method for soda acid, the technology of getting soda acid through the bipolar membrane electrodialysis legal system at the waste liquid that is applied to produce in the viscose fiber strand moulding process only, adopt specific recovery method, pre-treatment step in the recovery method is handled the waste liquid that produces in the viscose fiber strand moulding process, enter the bipolar membrane electrodialysis process again, improved the reclaim recovery efficiency of bronsted lowry acids and bases bronsted lowry in the viscose fiber waste liquid, reduced the damage that waste liquid impurity causes Bipolar Membrane, improve the work-ing life of Bipolar Membrane, and guarantee carrying out smoothly of bipolar membrane electrodialysis and subsequent handling.
In order to realize the foregoing invention purpose, concrete technical scheme of the present invention is as follows:
A kind of viscose fiber sodium sulfate waste liquid adopts the bipolar membrane electrodialysis method to reclaim the method for soda acid, it is characterized in that may further comprise the steps successively: crystallization, regulate pH, prefiltration, O
3Oxidation-reduction quality material, secondary prefiltration, gac are removed that organism, ion exchange resin are removed zine ion, the smart filter of pp millipore filtration, soda acid is produced and are concentrated;
Described crystallization by with in the viscose fiber strand moulding process the generation sodium sulphate content be that the waste liquid of 200-400g/L generates sodium sulfate crystal by high temperature crystallization;
Described adjusting pH is for dissolving sodium sulfate crystal with de-mineralized water earlier, obtain the metabisulfite solution that concentration is 3%-15%, in metabisulfite solution, add yellow soda ash again, with pH value of solution value modulation 8-10, adding yellow soda ash can be with the maximized precipitation of the zine ion in the metabisulfite solution, solid-liquid separation reclaims zinc and reduces zinc ion content in the metabisulfite solution;
Described through adding the metabisulfite solution of yellow soda ash depositing zinc ion, through a prefiltration, i.e. plate filter, remove the zine ion throw out, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, prolong the work-ing life of equipment, improved yield and the quality of product;
Described through the metabisulfite solution behind prefiltration, adopt O
3Oxidation style is removed the reducing substances of metabisulfite solution, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, avoided bipolar membrane electrodialysis equipment under the situation of electrolysis, make film and reducing substances generation redox reaction and damage, prolong the work-ing life of equipment, improved the quality of product;
Described through O
3Metabisulfite solution behind the oxidation removal reducing substances filters through the secondary flame filter press, can go out large granular impurity in the metabisulfite solution effectively, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, prolong the work-ing life of equipment, improved the quality of product;
Metabisulfite solution behind the described process secondary prefiltration passes through the gac device again, can effectively remove organic substance and some fine particles, avoid organic substance enrichment and influence the performance of film in the Bipolar Membrane equipment, prolonged the work-ing life of equipment, improved yield and the quality of product;
Described through the process of the metabisulfite solution after activated carbon treatment ion exchange resin system, the remaining zine ion in the removal solution makes divalent-metal ion drop to minimum to the influence of bipolar membrane electrodialysis;
Described metabisulfite solution through the ion exchange resin system is filtered through the pp millipore filter is smart again, can obtain meeting the treatment solution that enters bipolar membrane electrodialysis film group device index;
Described soda acid is produced to treatment solution gets concentration through the bipolar membrane electrodialysis legal system and is controlled to be the sulphuric acid soln of 1-30g/l and the sodium hydroxide solution that concentration is controlled to be 5-80g/l;
Described simmer down to adopts method of evaporation with the sulphuric acid soln that concentration is controlled to be 1-30g/l; After concentrating, the sulphuric acid soln that concentration is controlled to be 80-320g/l is transported to and carries out sulfuric acid in the acid bath operation of viscose fiber production and add, and forms online sulfuric acid circulation recycling system; The sodium hydroxide solution that concentration is controlled to be 5-80g/l adopts method of evaporation to concentrate, through method of evaporation concentrate sheet steeping operation that sodium hydroxide solution that back concentration is controlled to be 50%-100% is transported to viscose fiber production, soda cellulose sulphonate dissolution process, waste gas absorption operation, concise compressing and washing carried out sodium hydroxide in operation and the sour water neutralizing treatment operation and added, and forms online alkali circulation recycling system.Reduce the input amount of sulfuric acid and sodium hydroxide, thereby reduced the viscose fiber production cost.
Ss concentration is less than 5mg/l in the described treatment solution, and COD is less than 60mg/l, and zinc ion concentration is less than 5mg/l, and the temperature for the treatment of solution is 5-35 ° of C.
In the described crystallisation step, Tc is 40-80 ℃, and crystallization time is 5-30min, obtains 92% sodium sulfate crystal.
Described gac is removed in the organism step, adopts corpuscular active carbon adsorption column.
In the smart filter of the described pp millipore filtration step, the aperture of micropore filtering film is the 0.22-1 micron in the PP strainer.
Flame filter press and PP strainer are physical filtering, and flame filter press filters out a certain size large granular impurity and the suspended substance in the metabisulfite solution, and the PP strainer filters out the material of the small radii in the metabisulfite solution.
The useful technique effect that the present invention brings:
1, the present invention solves the waste liquid that existing application produces and reclaims problem and the defective that the soda acid technology exists through the bipolar membrane electrodialysis method in viscose fiber strand moulding process, adopt specific recovery method, pre-treatment step in the recovery method is handled the waste liquid that produces in the viscose fiber strand moulding process, enter the bipolar membrane electrodialysis process again, improved the reclaim recovery efficiency of bronsted lowry acids and bases bronsted lowry in the viscose fiber waste liquid, reduced the damage that waste liquid impurity causes Bipolar Membrane, improve the work-ing life of Bipolar Membrane, and guarantee carrying out smoothly of bipolar membrane electrodialysis and subsequent handling.
2, the present invention's concentration that treatment solution is made sodium hydroxide solution is controlled to be 5-80g/l, and the concentration of sulphuric acid soln is controlled to be 1-30g/l; Can be well cooperate with follow-up enrichment process, realize online reclaim(ed) sulfuric acid and sodium hydroxide.
3, the present invention adopts sulphuric acid soln and sodium hydroxide solution is concentrated respectively, and after concentrating, the concentration of sulphuric acid soln is 80-320g/l, and the concentration of sodium hydroxide solution is 50%-100%; Sulphuric acid soln can be transported to and carry out sulfuric acid in the acid bath operation of viscose fiber production and add; The sheet steeping operation, soda cellulose sulphonate dissolution process, waste gas that sodium hydroxide solution can be transported to viscose fiber production absorbs operation, concise compressing and washing carried out sodium hydroxide in operation and the sour water neutralizing treatment operation and added, can form the recycle system, reduce the input amount of sulfuric acid and sodium hydroxide, thereby reduced the viscose fiber production cost.
4, the present invention adopts method of evaporation that alkali is concentrated, and is reclaiming the alkali that alkali concn is controlled to be 50%-100%, and effect is remarkable, saves cost, can directly reclaim, and further improves the concentration that reclaims alkali; Be recovered to viscose glue production with carrying out adding of alkali in the alkali operation, reduce production costs; Also can obtain alkali concn and be controlled to be 96%, 98% and 99% sodium hydroxide crystal, but direct marketing brings benefits.
Embodiment
Below enforcement of the present invention is specified:
Embodiment 1
A kind of viscose fiber sodium sulfate waste liquid adopts the bipolar membrane electrodialysis method to reclaim the method for soda acid, may further comprise the steps successively: crystallization, regulate pH, prefiltration, O
3Oxidation-reduction quality material, secondary prefiltration, gac are removed that organism, ion exchange resin are removed zine ion, the smart filter of pp millipore filtration, soda acid is produced and are concentrated;
Described crystallization by with in the viscose fiber strand moulding process the generation sodium sulphate content be that the waste liquid of 200g/L generates sodium sulfate crystal by high temperature crystallization;
Described adjusting pH is for dissolving sodium sulfate crystal with de-mineralized water earlier, obtain concentration and be 3% metabisulfite solution, in metabisulfite solution, add yellow soda ash again, with pH value of solution value modulation 8, adding yellow soda ash can be easy to the maximized precipitation of the zine ion in the metabisulfite solution to separate, and allows the metabisulfite solution of the few zine ion of content enter in the bipolar membrane electrodialysis film group device, prolong the work-ing life of equipment, improved yield and the quality of product;
Described through adding the metabisulfite solution of yellow soda ash depositing zinc ion, through a prefiltration, i.e. plate filter, remove the zine ion throw out, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, prolonged the work-ing life of equipment, improved the quality of product;
Described through the metabisulfite solution behind prefiltration, adopt O
3Oxidation style is removed the reducing substances of metabisulfite solution, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, avoided bipolar membrane electrodialysis equipment under the situation of electrolysis, make the material redox of being reduced property of film and damage, prolong the work-ing life of equipment, improved the quality of product;
Described through O
3Metabisulfite solution behind the oxidation removal reducing substances filters through the secondary flame filter press, can go out large granular impurity in the metabisulfite solution effectively, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, prolong the work-ing life of equipment, improved the quality of product;
Metabisulfite solution behind the described process secondary prefiltration passes through the gac device again, can effectively remove organic substance and some fine particles, avoid organic substance enrichment and influence the performance of film in the Bipolar Membrane equipment, prolonged the work-ing life of equipment, improved yield and the quality of product;
Described through the process of the metabisulfite solution after activated carbon treatment ion exchange resin system, the remaining zine ion in the removal solution makes divalent-metal ion drop to minimum to the influence of bipolar membrane electrodialysis;
Described metabisulfite solution through the ion exchange resin system is filtered through the pp millipore filter is smart again, can obtain meeting the treatment solution that enters bipolar membrane electrodialysis film group device index;
Described simmer down to adopts method of evaporation to concentrate the sulphuric acid soln that concentration is controlled to be 1g/l; After concentrating, the sulphuric acid soln that concentration is controlled to be 80g/l is transported to and carries out sulfuric acid in the acid bath operation of viscose fiber production and add, and forms online sulfuric acid circulation recycling system; The sodium hydroxide solution that concentration is controlled to be 5g/l adopts method of evaporation to concentrate, concentrate through method of evaporation that back concentration is controlled to be sheet steeping operation that 50% sodium hydroxide solution is transported to viscose fiber production, soda cellulose sulphonate dissolution process, waste gas absorption operation, concise compressing and washing carried out sodium hydroxide in operation and the sour water neutralizing treatment operation and added, form online alkali circulation recycling system.Reduce the input amount of sulfuric acid and sodium hydroxide, thereby reduced the viscose fiber production cost.
Ss concentration is less than 5mg/l in the described treatment solution, and COD is less than 60mg/l, and zinc ion concentration is less than 5mg/l, and the temperature for the treatment of solution is 5 ° of C.
In the described crystallisation step, Tc is 40 ℃, and crystallization time is 30min, obtains 92% sodium sulfate crystal.
Described gac is removed in the organism step, adopts corpuscular active carbon adsorption column.
In the smart filter of the described pp millipore filtration step, the aperture of micropore filtering film is 0.22 micron in the PP strainer.
Flame filter press and PP strainer are physical filtering, and flame filter press filters out a certain size large granular impurity and the suspended substance in the metabisulfite solution, and the PP strainer filters out the material of the small radii in the metabisulfite solution.
A kind of bipolar membrane electrodialysis method that the present invention adopts the applicant to apply for simultaneously when using is handled the method for viscose fiber sodium sulfate waste liquid, is 5% viscose fiber sodium sulfate waste liquid with sodium sulfate concentration through crystallization, regulates pH, prefiltration, O
3Oxidation-reduction quality material, secondary prefiltration, gac are removed organism, ion exchange resin is removed zine ion and the smart filter of pp millipore filtration, enter then in the sodium sulfate runner of bipolar membrane electrodialysis film group device; De-mineralized water as absorption liquid enters respectively in the sour runner and alkali runner of bipolar membrane electrodialysis film group device, makes sulphuric acid soln and sodium hydroxide solution; The work gauge pressure of described bipolar membrane electrodialysis film group device is 0.03MPa.
The basement membrane of described Bipolar Membrane is that alloy firm with polyethylene and ethene and octene copolymer elastomerics and polyisobutylene rubber tertiary blending is as basilar membrane, immersion contains in the solution of vinylbenzene, divinylbenzene and benzoyl peroxide, the film that soaked liquid pressurizes again, and polymerization obtains under heating.
The thickness of described basement membrane is 0.05mm.
When concrete the use, select BPM2-2500-3 type bipolar membrane electrodialysis film group device for use, comprising: 120V*150A D.C. regulated power supply, 400*800 bipolar membrane electrodialysis film group device (comprising resistance sorrel, resistance alkali film and Bipolar Membrane), evaporation concentration equipment and heat pump; Adopt heat pump to the processing of lowering the temperature of bipolar membrane electrodialysis film group device, heat pump can carry out recycling to evaporation concentration equipment with heat recuperation.
The cleaning step of bipolar membrane electrodialysis film group device comprises: 1, the sodium sulfate loop exit place feeding de-mineralized water toward the bipolar membrane electrodialysis film group device carries out back flushing to remove equipment runner and the less particulate matter of Bipolar Membrane adhering on surface to the bipolar membrane electrodialysis film group device, till back flushing is normal to working pressure; 2, be that 25 degree, compound concentration are till 1% sodium hydroxide solution recovers to electric current Bipolar Membrane surface wash cycles with temperature.
Embodiment 2
A kind of viscose fiber sodium sulfate waste liquid adopts the bipolar membrane electrodialysis method to reclaim the method for soda acid, may further comprise the steps successively: crystallization, regulate pH, prefiltration, O
3Oxidation-reduction quality material, secondary prefiltration, gac are removed that organism, ion exchange resin are removed zine ion, the smart filter of pp millipore filtration, soda acid is produced and are concentrated;
Described crystallization by with in the viscose fiber strand moulding process the generation sodium sulphate content be that the waste liquid of 300g/L generates sodium sulfate crystal by high temperature crystallization;
Described adjusting pH is for dissolving sodium sulfate crystal with de-mineralized water earlier, obtain concentration and be 7% metabisulfite solution, in metabisulfite solution, add yellow soda ash again, with pH value of solution value modulation 9, adding yellow soda ash can be easy to the maximized precipitation of the zine ion in the metabisulfite solution to separate, and allows the metabisulfite solution of the few zine ion of content enter in the bipolar membrane electrodialysis film group device, prolong the work-ing life of equipment, improved yield and the quality of product;
Described through adding the metabisulfite solution of yellow soda ash depositing zinc ion, through a prefiltration, i.e. plate filter, remove the zine ion throw out, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, prolonged the work-ing life of equipment, improved the quality of product;
Described through the metabisulfite solution behind prefiltration, adopt O
3Oxidation style is removed the reducing substances of metabisulfite solution, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, avoided bipolar membrane electrodialysis equipment under the situation of electrolysis, make the material redox of being reduced property of film and damage, prolong the work-ing life of equipment, improved the quality of product;
Described through O
3Metabisulfite solution behind the oxidation removal reducing substances filters through the secondary flame filter press, can go out large granular impurity in the metabisulfite solution effectively, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, prolong the work-ing life of equipment, improved the quality of product;
Metabisulfite solution behind the described process secondary prefiltration passes through the gac device again, can effectively remove organic substance and some fine particles, avoid organic substance enrichment and influence the performance of film in the Bipolar Membrane equipment, prolonged the work-ing life of equipment, improved yield and the quality of product;
Described through the process of the metabisulfite solution after activated carbon treatment ion exchange resin system, the remaining zine ion in the removal solution makes divalent-metal ion drop to minimum to the influence of bipolar membrane electrodialysis;
Described metabisulfite solution through the ion exchange resin system is filtered through the pp millipore filter is smart again, can obtain meeting the treatment solution that enters bipolar membrane electrodialysis film group device index;
Described simmer down to adopts method of evaporation to concentrate the sulphuric acid soln that concentration is controlled to be 10g/l; After concentrating, the sulphuric acid soln that concentration is controlled to be 100g/l is transported to and carries out sulfuric acid in the acid bath operation of viscose fiber production and add, and forms online sulfuric acid circulation recycling system; The sodium hydroxide solution that concentration is controlled to be 10g/l adopts method of evaporation to concentrate, concentrate through method of evaporation that back concentration is controlled to be sheet steeping operation that 60% sodium hydroxide solution is transported to viscose fiber production, soda cellulose sulphonate dissolution process, waste gas absorption operation, concise compressing and washing carried out sodium hydroxide in operation and the sour water neutralizing treatment operation and added, form online alkali circulation recycling system.Reduce the input amount of sulfuric acid and sodium hydroxide, thereby reduced the viscose fiber production cost.
Ss concentration is less than 5mg/l in the described treatment solution, and COD is less than 60mg/l, and zinc ion concentration is less than 5mg/l, and the temperature for the treatment of solution is 20 ° of C.
In the described crystallisation step, Tc is 60 ℃, and crystallization time is 15min, obtains 92% sodium sulfate crystal.
Described gac is removed in the organism step, adopts corpuscular active carbon adsorption column.
In the smart filter of the described pp millipore filtration step, the aperture of micropore filtering film is 0.22 micron in the PP strainer.
Flame filter press and PP strainer are physical filtering, and flame filter press filters out a certain size large granular impurity and the suspended substance in the metabisulfite solution, and the PP strainer filters out the material of the small radii in the metabisulfite solution.
A kind of bipolar membrane electrodialysis method that the present invention adopts the applicant to apply for simultaneously when using is handled the method for viscose fiber sodium sulfate waste liquid, is 10% viscose fiber sodium sulfate waste liquid with sodium sulfate concentration through crystallization, regulates pH, prefiltration, O
3Oxidation-reduction quality material, secondary prefiltration, gac are removed organism, ion exchange resin is removed zine ion and the smart filter of pp millipore filtration, enter then in the sodium sulfate runner of bipolar membrane electrodialysis film group device; De-mineralized water as absorption liquid enters respectively in the sour runner and alkali runner of bipolar membrane electrodialysis film group device, makes sulphuric acid soln and sodium hydroxide solution; The work gauge pressure of described bipolar membrane electrodialysis film group device is 0.04MPa.
The basement membrane of described Bipolar Membrane is that alloy firm with polyethylene and ethene and octene copolymer elastomerics and polyisobutylene rubber tertiary blending is as basilar membrane, immersion contains in the solution of vinylbenzene, divinylbenzene and benzoyl peroxide, the film that soaked liquid pressurizes again, and polymerization obtains under heating.
The thickness of described basement membrane is 0.05mm.
When concrete the use, select BPM2-2500-3 type bipolar membrane electrodialysis film group device for use, comprising: 120V*150A D.C. regulated power supply, 400*800 bipolar membrane electrodialysis film group device (comprising resistance sorrel, resistance alkali film and Bipolar Membrane), evaporation concentration equipment and heat pump; Adopt heat pump to the processing of lowering the temperature of bipolar membrane electrodialysis film group device, heat pump can carry out recycling to evaporation concentration equipment with heat recuperation.
The cleaning step of bipolar membrane electrodialysis film group device comprises: 1, the sodium sulfate loop exit place feeding de-mineralized water toward the bipolar membrane electrodialysis film group device carries out back flushing to remove equipment runner and the less particulate matter of Bipolar Membrane adhering on surface to the bipolar membrane electrodialysis film group device, till back flushing is normal to working pressure; 2, be that 28 degree, compound concentration are till 2% sodium hydroxide solution recovers to electric current Bipolar Membrane surface wash cycles with temperature.
Embodiment 3
A kind of viscose fiber sodium sulfate waste liquid adopts the bipolar membrane electrodialysis method to reclaim the method for soda acid, may further comprise the steps successively: crystallization, regulate pH, prefiltration, O
3Oxidation-reduction quality material, secondary prefiltration, gac are removed that organism, ion exchange resin are removed zine ion, the smart filter of pp millipore filtration, soda acid is produced and are concentrated;
Described crystallization by with in the viscose fiber strand moulding process the generation sodium sulphate content be that the waste liquid of 300g/L generates sodium sulfate crystal by high temperature crystallization;
Described adjusting pH is for dissolving sodium sulfate crystal with de-mineralized water earlier, obtain concentration and be 12% metabisulfite solution, in metabisulfite solution, add yellow soda ash again, with pH value of solution value modulation 9, adding yellow soda ash can be easy to the maximized precipitation of the zine ion in the metabisulfite solution to separate, and allows the metabisulfite solution of the few zine ion of content enter in the bipolar membrane electrodialysis film group device, prolong the work-ing life of equipment, improved yield and the quality of product;
Described through adding the metabisulfite solution of yellow soda ash depositing zinc ion, through a prefiltration, i.e. plate filter, remove the zine ion throw out, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, prolonged the work-ing life of equipment, improved the quality of product;
Described through the metabisulfite solution behind prefiltration, adopt O
3Oxidation style is removed the reducing substances of metabisulfite solution, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, avoided bipolar membrane electrodialysis equipment under the situation of electrolysis, make the material redox of being reduced property of film and damage, prolong the work-ing life of equipment, improved the quality of product;
Described through O
3Metabisulfite solution behind the oxidation removal reducing substances filters through the secondary flame filter press, can go out large granular impurity in the metabisulfite solution effectively, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, prolong the work-ing life of equipment, improved the quality of product;
Metabisulfite solution behind the described process secondary prefiltration passes through the gac device again, can effectively remove organic substance and some fine particles, avoid organic substance enrichment and influence the performance of film in the Bipolar Membrane equipment, prolonged the work-ing life of equipment, improved yield and the quality of product;
Described through the process of the metabisulfite solution after activated carbon treatment ion exchange resin system, the remaining zine ion in the removal solution makes divalent-metal ion drop to minimum to the influence of bipolar membrane electrodialysis;
Described metabisulfite solution through the ion exchange resin system is filtered through the pp millipore filter is smart again, can obtain meeting the treatment solution that enters bipolar membrane electrodialysis film group device index;
Described simmer down to adopts method of evaporation to concentrate the sulphuric acid soln that concentration is controlled to be 15g/l; After concentrating, the sulphuric acid soln that concentration is controlled to be 150g/l is transported to and carries out sulfuric acid in the acid bath operation of viscose fiber production and add, and forms online sulfuric acid circulation recycling system; The sodium hydroxide solution that concentration is controlled to be 15g/l adopts method of evaporation to concentrate, concentrate through method of evaporation that back concentration is controlled to be sheet steeping operation that 70% sodium hydroxide solution is transported to viscose fiber production, soda cellulose sulphonate dissolution process, waste gas absorption operation, concise compressing and washing carried out sodium hydroxide in operation and the sour water neutralizing treatment operation and added, form online alkali circulation recycling system.Reduce the input amount of sulfuric acid and sodium hydroxide, thereby reduced the viscose fiber production cost.
Ss concentration is less than 5mg/l in the described treatment solution, and COD is less than 60mg/l, and zinc ion concentration is less than 5mg/l, and the temperature for the treatment of solution is 20 ° of C.
In the described crystallisation step, Tc is 60 ℃, and crystallization time is 15min, obtains 92% sodium sulfate crystal.
Described gac is removed in the organism step, adopts corpuscular active carbon adsorption column.
In the smart filter of the described pp millipore filtration step, the aperture of micropore filtering film is 0.22 micron in the PP strainer.
Flame filter press and PP strainer are physical filtering, and flame filter press filters out a certain size large granular impurity and the suspended substance in the metabisulfite solution, and the PP strainer filters out the material of the small radii in the metabisulfite solution.
A kind of bipolar membrane electrodialysis method that the present invention adopts the applicant to apply for simultaneously when using is handled the method for viscose fiber sodium sulfate waste liquid, is 15% viscose fiber sodium sulfate waste liquid with sodium sulfate concentration through crystallization, regulates pH, prefiltration, O
3Oxidation-reduction quality material, secondary prefiltration, gac are removed organism, ion exchange resin is removed zine ion and the smart filter of pp millipore filtration, enter then in the sodium sulfate runner of bipolar membrane electrodialysis film group device; De-mineralized water as absorption liquid enters respectively in the sour runner and alkali runner of bipolar membrane electrodialysis film group device, makes sulphuric acid soln and sodium hydroxide solution; The work gauge pressure of described bipolar membrane electrodialysis film group device is 0.04MPa.
The basement membrane of described Bipolar Membrane is that alloy firm with polyethylene and ethene and octene copolymer elastomerics and polyisobutylene rubber tertiary blending is as basilar membrane, immersion contains in the solution of vinylbenzene, divinylbenzene and benzoyl peroxide, the film that soaked liquid pressurizes again, and polymerization obtains under heating.
The thickness of described basement membrane is 0.05mm.
When concrete the use, select BPM2-2500-3 type bipolar membrane electrodialysis film group device for use, comprising: 120V*150A D.C. regulated power supply, 400*800 bipolar membrane electrodialysis film group device (comprising resistance sorrel, resistance alkali film and Bipolar Membrane), evaporation concentration equipment and heat pump; Adopt heat pump to the processing of lowering the temperature of bipolar membrane electrodialysis film group device, heat pump can carry out recycling to evaporation concentration equipment with heat recuperation.
The cleaning step of bipolar membrane electrodialysis film group device comprises: 1, the sodium sulfate loop exit place feeding de-mineralized water toward the bipolar membrane electrodialysis film group device carries out back flushing to remove equipment runner and the less particulate matter of Bipolar Membrane adhering on surface to the bipolar membrane electrodialysis film group device, till back flushing is normal to working pressure; 2, be that 30 degree, compound concentration are till 3% sodium hydroxide solution recovers to electric current Bipolar Membrane surface wash cycles with temperature.
Embodiment 4
A kind of viscose fiber sodium sulfate waste liquid adopts the bipolar membrane electrodialysis method to reclaim the method for soda acid, may further comprise the steps successively: crystallization, regulate pH, prefiltration, O
3Oxidation-reduction quality material, secondary prefiltration, gac are removed that organism, ion exchange resin are removed zine ion, the smart filter of pp millipore filtration, soda acid is produced and are concentrated;
Described crystallization by with in the viscose fiber strand moulding process the generation sodium sulphate content be that the waste liquid of 400g/L generates sodium sulfate crystal by high temperature crystallization;
Described adjusting pH is for dissolving sodium sulfate crystal with de-mineralized water earlier, obtain concentration and be 15% metabisulfite solution, in metabisulfite solution, add yellow soda ash again, with pH value of solution value modulation 10, adding yellow soda ash can be easy to the maximized precipitation of the zine ion in the metabisulfite solution to separate, and allows the metabisulfite solution of the few zine ion of content enter in the bipolar membrane electrodialysis film group device, prolong the work-ing life of equipment, improved yield and the quality of product;
Described through adding the metabisulfite solution of yellow soda ash depositing zinc ion, through a prefiltration, i.e. plate filter, remove the zine ion throw out, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, prolonged the work-ing life of equipment, improved the quality of product;
Described through the metabisulfite solution behind prefiltration, adopt O
3Oxidation style is removed the reducing substances of metabisulfite solution, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, avoided bipolar membrane electrodialysis equipment under the situation of electrolysis, make the material redox of being reduced property of film and damage, prolong the work-ing life of equipment, improved the quality of product;
Described through O
3Metabisulfite solution behind the oxidation removal reducing substances filters through the secondary flame filter press, can go out large granular impurity in the metabisulfite solution effectively, allow comparatively pure metabisulfite solution enter in the bipolar membrane electrodialysis film group device, prolong the work-ing life of equipment, improved the quality of product;
Metabisulfite solution behind the described process secondary prefiltration passes through the gac device again, can effectively remove organic substance and some fine particles, avoid organic substance enrichment and influence the performance of film in the Bipolar Membrane equipment, prolonged the work-ing life of equipment, improved yield and the quality of product;
Described through the process of the metabisulfite solution after activated carbon treatment ion exchange resin system, the remaining zine ion in the removal solution makes divalent-metal ion drop to minimum to the influence of bipolar membrane electrodialysis;
Described metabisulfite solution through the ion exchange resin system is filtered through the pp millipore filter is smart again, can obtain meeting the treatment solution that enters bipolar membrane electrodialysis film group device index;
Described simmer down to adopts method of evaporation to concentrate the sulphuric acid soln that concentration is controlled to be 30g/l; After concentrating, the sulphuric acid soln that concentration is controlled to be 320g/l is transported to and carries out sulfuric acid in the acid bath operation of viscose fiber production and add, and forms online sulfuric acid circulation recycling system; The sodium hydroxide solution that concentration is controlled to be 80g/l adopts method of evaporation to concentrate, concentrate through method of evaporation that back concentration is controlled to be sheet steeping operation that 95% sodium hydroxide solution is transported to viscose fiber production, soda cellulose sulphonate dissolution process, waste gas absorption operation, concise compressing and washing carried out sodium hydroxide in operation and the sour water neutralizing treatment operation and added, form online alkali circulation recycling system.Reduce the input amount of sulfuric acid and sodium hydroxide, thereby reduced the viscose fiber production cost.
Ss concentration is less than 5mg/l in the described treatment solution, and COD is less than 60mg/l, and zinc ion concentration is less than 5mg/l, and the temperature for the treatment of solution is 35 ° of C.
In the described crystallisation step, Tc is 80 ℃, and crystallization time is 5min, obtains 92% sodium sulfate crystal.
Described gac is removed in the organism step, adopts corpuscular active carbon adsorption column.
In the smart filter of the described pp millipore filtration step, the aperture of micropore filtering film is 0.22 micron in the PP strainer.
Flame filter press and PP strainer are physical filtering, and flame filter press filters out a certain size large granular impurity and the suspended substance in the metabisulfite solution, and the PP strainer filters out the material of the small radii in the metabisulfite solution.
A kind of bipolar membrane electrodialysis method that the present invention adopts the applicant to apply for simultaneously when using is handled the method for viscose fiber sodium sulfate waste liquid, is 20% viscose fiber sodium sulfate waste liquid with sodium sulfate concentration through crystallization, regulates pH, prefiltration, O
3Oxidation-reduction quality material, secondary prefiltration, gac are removed organism, ion exchange resin is removed zine ion and the smart filter of pp millipore filtration, enter then in the sodium sulfate runner of bipolar membrane electrodialysis film group device; De-mineralized water as absorption liquid enters respectively in the sour runner and alkali runner of bipolar membrane electrodialysis film group device, makes sulphuric acid soln and sodium hydroxide solution; The work gauge pressure of described bipolar membrane electrodialysis film group device is 0.04MPa.
The basement membrane of described Bipolar Membrane is that alloy firm with polyethylene and ethene and octene copolymer elastomerics and polyisobutylene rubber tertiary blending is as basilar membrane, immersion contains in the solution of vinylbenzene, divinylbenzene and benzoyl peroxide, the film that soaked liquid pressurizes again, and polymerization obtains under heating.
The thickness of described basement membrane is 0.05mm.
When concrete the use, select BPM2-2500-3 type bipolar membrane electrodialysis film group device for use, comprising: 120V*150A D.C. regulated power supply, 400*800 bipolar membrane electrodialysis film group device (comprising resistance sorrel, resistance alkali film and Bipolar Membrane), evaporation concentration equipment and heat pump; Adopt heat pump to the processing of lowering the temperature of bipolar membrane electrodialysis film group device, heat pump can carry out recycling to evaporation concentration equipment with heat recuperation.
The cleaning step of bipolar membrane electrodialysis film group device comprises: 1, the sodium sulfate loop exit place feeding de-mineralized water toward the bipolar membrane electrodialysis film group device carries out back flushing to remove equipment runner and the less particulate matter of Bipolar Membrane adhering on surface to the bipolar membrane electrodialysis film group device, till back flushing is normal to working pressure; 2, be that 35 degree, compound concentration are till 5% sodium hydroxide solution recovers to electric current Bipolar Membrane surface wash cycles with temperature.
Embodiment 5
The present invention concentrates in method of evaporation and can obtain between the alkali lye or crystal that alkali concn is controlled to be 50%-100%, can carry out the concentration that reverse osmosis method concentrates, electroosmose process concentrates, the low-temperature multi-effect method concentrates and the multiple-effect evaporation method concentrates alkali lye successively is concentrated in the scope of 30%-50% gradually, concentrate through method of evaporation again and can obtain alkali lye or the crystal that alkali concn is controlled to be 50%-100%, further improve the concentration that reclaims alkali; Be recovered to viscose glue production with carrying out adding of alkali in the alkali operation, reduce production costs, but particularly alkali concn is controlled to be 96%, 98% and 99% sodium hydroxide crystal direct marketing, brings benefits.
Claims (6)
1. a viscose fiber sodium sulfate waste liquid adopts the bipolar membrane electrodialysis method to reclaim the method for soda acid, it is characterized in that may further comprise the steps successively: crystallization, regulate pH, prefiltration, O
3Oxidation-reduction quality material, secondary prefiltration, gac are removed that organism, ion exchange resin are removed zine ion, the smart filter of pp millipore filtration, soda acid is produced and are concentrated;
Described crystallization by with in the viscose fiber strand moulding process the generation sodium sulphate content be that the waste liquid of 200-400g/L generates sodium sulfate crystal by high temperature crystallization;
Described adjusting pH obtains the metabisulfite solution that concentration is 3%-15% for dissolving sodium sulfate crystal with de-mineralized water earlier, adds yellow soda ash again in metabisulfite solution, with pH value of solution value modulation 8-10;
Described through adding the metabisulfite solution of yellow soda ash depositing zinc ion, through a prefiltration, namely a plate filter is removed the zine ion throw out;
Described through the metabisulfite solution behind prefiltration, adopt O
3Oxidation style is removed the reducing substances of metabisulfite solution;
Described through O
3Metabisulfite solution behind the oxidation removal reducing substances filters through the secondary flame filter press, removes the large granular impurity in the metabisulfite solution;
Metabisulfite solution behind the described process secondary prefiltration passes through the gac device again, removes organic substance and some fine particles;
Described through the process of the metabisulfite solution after activated carbon treatment ion exchange resin system, remove the remaining zine ion in the solution;
Described metabisulfite solution through the ion exchange resin system is filtered through the pp millipore filter is smart again, obtains meeting the treatment solution that enters bipolar membrane electrodialysis film group device index;
Described soda acid is produced to treatment solution gets concentration through the bipolar membrane electrodialysis legal system and is controlled to be the sulphuric acid soln of 1-30g/l and the sodium hydroxide solution that concentration is controlled to be 5-80g/l;
Described simmer down to adopts method of evaporation with the sulphuric acid soln that concentration is controlled to be 1-30g/l; After concentrating, obtain the sulphuric acid soln that concentration is controlled to be 80-320g/l; The sodium hydroxide solution that concentration is controlled to be 5-80g/l adopts method of evaporation to concentrate, and obtains the sodium hydroxide solution that concentration is controlled to be 50%-100% after method of evaporation concentrates.
2. adopt the bipolar membrane electrodialysis method to reclaim the method for soda acid according to the described a kind of viscose fiber sodium sulfate waste liquid of claim 1, it is characterized in that: ss concentration is less than 5mg/l in the described treatment solution, COD is less than 60mg/l, and zinc ion concentration is less than 5mg/l, and the temperature for the treatment of solution is 5-35 ° of C.
3. adopt the bipolar membrane electrodialysis method to reclaim the method for soda acid according to the described a kind of viscose fiber sodium sulfate waste liquid of claim 1, it is characterized in that: in the described crystallisation step, Tc is 40-80 ℃, and crystallization time is 5-30min, obtains 92% sodium sulfate crystal.
4. adopt the bipolar membrane electrodialysis method to reclaim the method for soda acid according to the described a kind of viscose fiber sodium sulfate waste liquid of claim 1, it is characterized in that: described gac is removed in the organism step, adopts corpuscular active carbon adsorption column.
5. adopt the bipolar membrane electrodialysis method to reclaim the method for soda acid according to the described a kind of viscose fiber sodium sulfate waste liquid of claim 1, it is characterized in that: in the smart filter of the described pp millipore filtration step, the aperture of micropore filtering film is the 0.22-1 micron in the PP strainer.
6. adopt the bipolar membrane electrodialysis method to reclaim the method for soda acid according to the described a kind of viscose fiber sodium sulfate waste liquid of claim 1, it is characterized in that: flame filter press and PP strainer are physical filtering, flame filter press filters out a certain size large granular impurity and the suspended substance in the metabisulfite solution, and the PP strainer filters out the material of the small radii in the metabisulfite solution.
Priority Applications (1)
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| CN112758957A (en) * | 2020-12-28 | 2021-05-07 | 宜宾丝丽雅股份有限公司 | Process for purifying sodium hydroxide concentration by electrodialysis |
| CN112853550A (en) * | 2020-12-28 | 2021-05-28 | 宜宾丝丽雅股份有限公司 | Treatment method for recycling alkali liquor |
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Denomination of invention: A method for recovering acid and alkali from sodium sulfate waste liquid of viscose fiber using bipolar membrane electrodialysis Granted publication date: 20140702 Pledgee: Yibin Development Holding Group Co.,Ltd. Pledgor: YIBIN GRACE GROUP Co.,Ltd.|YIBIN GRACE Co.,Ltd.|YIBIN HIEST FIBRE Ltd.,Corp.|YIBIN HAIXIANG CHEMICAL CO.,LTD. Registration number: Y2024980030863 |
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