CN111170340A - Method for recovering salt and nitrate from salt and nitrate waste brine - Google Patents
Method for recovering salt and nitrate from salt and nitrate waste brine Download PDFInfo
- Publication number
- CN111170340A CN111170340A CN202010036715.8A CN202010036715A CN111170340A CN 111170340 A CN111170340 A CN 111170340A CN 202010036715 A CN202010036715 A CN 202010036715A CN 111170340 A CN111170340 A CN 111170340A
- Authority
- CN
- China
- Prior art keywords
- salt
- ions
- brine
- waste brine
- membrane
- 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.)
- Pending
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
- C01D5/16—Purification
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D3/00—Halides of sodium, potassium or alkali metals in general
- C01D3/04—Chlorides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D3/00—Halides of sodium, potassium or alkali metals in general
- C01D3/14—Purification
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/02—Treatment of water, waste water, or sewage by heating
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
- C02F1/442—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by nanofiltration
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
- C02F1/444—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by ultrafiltration or microfiltration
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/54—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using organic material
- C02F1/56—Macromolecular compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F2001/007—Processes including a sedimentation step
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/06—Controlling or monitoring parameters in water treatment pH
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F5/00—Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents
- C02F5/02—Softening water by precipitation of the hardness
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention discloses a method for recovering salt and nitrate from salt and nitrate waste brine, which comprises the following steps: the chemical softening method is adopted to enable scaling ions in the waste brine to generate precipitate, solid-liquid separation is realized through flocculation precipitation, supernatant enters an ultrafiltration process to reduce suspended particles in the brine, the softened and ultrafiltered brine passes through a nanofiltration membrane system, divalent and above valence state ions are intercepted, and produced water contains monovalent ions. The water produced is subjected to crystallization and evaporation process to obtain a solid crystal salt product, or the solid crystal salt product is directly sold as a liquid salt product in chemical industry, chlor-alkali industry and other industries, divalent ions such as sulfate radical in concentrated water of a nanofiltration system are concentrated, and the concentrated ions are returned to the production process to recover sodium sulfate. The method can solve the problem of environmental protection treatment of high-concentration waste brine in salt manufacturing enterprises, and simultaneously can realize the purpose of resource recovery of valuable components in the waste brine, thereby achieving multiple economic and social benefits of enterprise benefit, environmental protection treatment, resource recovery and recycling economy.
Description
Technical Field
The invention relates to a method for recovering resources from tail water mother liquor in salt manufacturing industry, in particular to a method for recovering sodium chloride and sodium sulfate from waste brine with high salt and nitrate content.
Background
The salt-making industry produces food-grade or industrial-grade sodium chloride, the raw material brine generally contains impurity ions such as calcium, magnesium, sulfate radical and the like, the industry mainly adopts methods such as evaporation, crystallization, washing and the like to obtain high-purity sodium chloride, in the evaporation crystallization process, other impurity ions are also concentrated and crystallized, although a small amount of impurity ions can be dissolved and removed again in the washing process, impurity salt such as sodium sulfate with higher content is partially recycled to obtain industrial-grade miscellaneous nitre with low purity, the sodium chloride content in tail water mother liquor after salt nitre extraction reaches more than 290g/L, the sodium sulfate content reaches 40g/L, the salt is made by adopting the traditional evaporation crystallization and elution processes, the recovery rate of the sodium chloride is not high, the obtained miscellaneous nitre has unstable quality, and therefore, the miscellaneous nitre cannot be continuously utilized or has larger difficulty and low comprehensive benefit, and is mostly returned to a brine mining area by adopting a back, the accumulation of the impurity ions is long, the impurity content in the extracted brine is higher and higher, and the evaporation crystallization and recovery benefits are reduced continuously.
By material balance, 30m of a small and medium-sized salt manufacturing enterprise3The discharge amount per hr is taken as an example, the total amount of salt and nitrate discharged annually is about 8 ten thousand tons in the tail water mother liquor according to the dry-based solid content, and if the salt and nitrate can be purified and recovered by adopting a proper method, the market value is huge, and better economic benefit can be brought to enterprises.
With the national vigorous promotion of the concept of circular economy, the requirements of the environment-friendly and resource-saving society, the improvement of the environmental awareness and the environmental protection pressure, the environmental requirements on enterprises are higher and higher. The potential of self deep digging of enterprise is compelled, promotes technical index, realizes waste water reuse, consequently solves the discharge problem of the high saltpeter water of salt manufacturing enterprise's tail water well, is not only a serious environmental protection problem, more can promote enterprise's technical upgrade, improves production efficiency to through retrieving sodium chloride and sodium sulfate, produce extra economic benefits's the trend of making benefit to more.
The membrane denitration is an effective method in the chlor-alkali industry, for example, Chinese patent CN102417193A discloses a production method for improving the denitration capacity of the membrane method, and the method mainly focuses on light brine in an electrolytic dechlorination section in the chlor-alkali industry, wherein the content of impurities is low, and the separation difficulty is not large. US patent US005587083 discloses a method for removing multivalent ions in the chlor-alkali industry. However, no better treatment method exists at present for the salt separation treatment and resource utilization of the nearly saturated ultra-high concentration saltpeter waste brine.
Disclosure of Invention
Aiming at the technical problems in the related industrial production, the invention provides a method for recovering salt and nitrate from brine waste, which can overcome the defects in the prior art.
In order to achieve the technical purpose, the technical scheme of the invention is realized as follows:
a method for recovering salt and nitrate from brine waste comprises the following steps:
A) adding a softening agent into waste brine containing impurities, suspended matters, calcium, magnesium and other scaling ions by a chemical softening method, and adjusting the pH value to enable the scaling ions in the waste brine to generate precipitates;
B) adding a proper amount of flocculation aid into softened waste brine, aggregating suspended matters and generated precipitates in the waste brine into larger particles, settling the larger particles to form precipitates, performing solid-liquid separation by a solid-liquid separation unit, treating the solid precipitates as wastes, and returning the separated liquid to the front-end step A);
C) in order to ensure the use effect of the key step of the subsequent membrane separation, the supernatant fluid after the sedimentation step is subjected to an ultrafiltration process to further reduce small particles in water, and the backwashing concentrated solution after ultrafiltration is returned to the step B);
D) the softened and ultrafiltered waste brine enters a special selective nanofiltration membrane system, most of divalent and above valence ions are intercepted, and the produced water mainly contains monovalent ions;
E) monovalent ions in the produced water can be returned to the crystallization evaporation process to obtain a solid crystalline salt product or be sold as an industrial liquid salt product with a specific concentration content;
F) divalent and above valence state ions in the concentrated solution of the nanofiltration membrane system are concentrated and can be returned to the production process, and products such as mirabilite and the like are recovered by methods such as mother liquor recovery or low-temperature freezing and the like.
Further, the Total Dissolved Solids (TDS) of the waste brine in the step A) is 100-360g/L, wherein the TDS of monovalent salts is 100-300g/L, and the TDS of divalent and above salts is 10-60 g/L.
Further, monovalent salts include, but are not limited to: chlorides, bromides, iodides, nitrates, and the like of alkali metals such as lithium, sodium, and potassium.
Further, salts of divalent and above include, but are not limited to: sulfates, carbonates, phosphates of metals such as calcium, magnesium, iron, copper, zinc, chromium, manganese, cadmium, and the like.
Further, the content of sodium chloride and the content of sodium sulfate in the waste brine in the step A) are respectively 100-300g/L and 10-60 g/L.
Further, sources of the waste brine in step a) include, but are not limited to, the following fields: high-concentration tail water in the salt making industry, high-salinity wastewater in the nitrate making industry, mother liquor in salt making from seawater, mother liquor after salt extraction in salt lakes, near-saturated mother liquor after zero-discharge evaporation and crystallization of industrial wastewater and high-concentration salt water subjected to zero-discharge miscellaneous salt harmless treatment.
Further, the softening agent in step a) includes, but is not limited to, one or more of caustic soda, sodium carbonate, sodium bicarbonate, and calcium hydroxide.
Further, the flocculation aid in step B) includes, but is not limited to, one or more of polyaluminium chloride, polyferric chloride, and polyacrylamide.
Further, the ultrafiltration membrane of the ultrafiltration process in step C) includes, but is not limited to, external pressure type hollow fiber membrane, roll type membrane, tubular type membrane, ceramic membrane, etc.
Furthermore, the pore diameter of the ultrafiltration membrane is 1-0.01 μm.
Further, the nanofiltration membrane of the nanofiltration membrane system in the step D) is made of an interface polymerization material, the rejection rate of monovalent ions of the nanofiltration membrane is 10-50%, and the rejection rate of divalent and above valence ions of the nanofiltration membrane is 40-99%.
The invention has the beneficial effects that: the method for recovering salt and nitrate from the salt and nitrate waste brine reduces impurity ions such as calcium and magnesium in the waste brine by chemical softening on the basis of the composition of the waste brine in the salt manufacturing industry, removes particle impurities in the waste brine by a filtering mode, separates and purifies sodium chloride and sodium sulfate in the waste brine by membrane separation and purification, wherein the removal rate of the sodium sulfate on a water production side is more than 80%, and the concentrated brine on the water production side after the membrane separation can be sold as refined brine and can also be subjected to processes such as evaporation crystallization to recover industrial high-purity sodium chloride.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a process flow diagram of a method for recovering salt and saltpeter from saltpeter waste brine according to an embodiment of the invention;
in the figure: 1. the method comprises the following steps of feeding a barrel, 2, a softening unit, 3, a solid-liquid separation unit, 4, an ultrafiltration unit, 5, a nanofiltration separation unit, 6, light salt water, 7, a dosing unit, 8, solid precipitation, 9, ultrafiltration concentrated solution and 10, and nanofiltration concentrated solution.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the embodiments given herein are intended to be within the scope of the present invention.
Example 1
As shown in fig. 1, the method for recovering salt and nitrate from saltpeter waste brine according to the embodiment of the invention comprises the following steps:
A) the waste brine in the feed barrel 1 is tail water mother liquor in the salt making industry, the sodium chloride content of the waste brine is 278g/L, the sodium sulfate content is 60g/L, and Ca is added2+The content is 1.5mg/L,Mg2+feeding the waste brine into a softening unit 2, adding sodium bicarbonate with the addition of 20mg/L into the softening unit 2 (a reaction precipitation tank) filled with the waste brine through a dosing unit 7 under the stirring condition, adding sodium hydroxide to adjust the pH value to 9.5, and continuously stirring for 10 minutes to enable scaling ions in the waste brine to generate precipitates, wherein the content of the waste brine is 0.8mg/L and the SS (suspended substance) is 50 mg/L;
B) adding 5ppm polyacrylamide, stirring and settling for 20 minutes, aggregating suspended matters and generated precipitates in the waste brine into larger particles, settling to form precipitates, performing solid-liquid separation by a solid-liquid separation unit 3, treating solid precipitates 8 as wastes, and returning the separated liquid to the front-end step A);
C) in order to ensure the use effect of the key step of the subsequent membrane separation, the supernatant after the sedimentation step needs to be subjected to an ultrafiltration process, the supernatant enters an ultrafiltration unit 4 through a feed pump to further reduce small particles in water, an ultrafiltration concentrated solution 9 (an ultrafiltration backwashing concentrated solution) returns to the step B), the ultrafiltration unit 4 is a tubular ultrafiltration system, the aperture of a tubular membrane of the tubular ultrafiltration system is 1-0.01 μm, the operating pressure is 0.35MPa, and the NaCl content of the ultrafiltration product water: 278g/L, Na2SO4The content is as follows: 60g/L, Ca2+The content is as follows: 0.2Mg/L, Mg2+The content is as follows: 0.1mg/L, SS: 3 mg/L;
D) the softened and ultrafiltered waste brine is pressurized by a high-pressure pump and then is separated by a nanofiltration separation unit 5 (a special selective nanofiltration membrane), most of divalent and above valence ions are intercepted, the produced water mainly contains monovalent ions, the nanofiltration membrane of the nanofiltration membrane system is made of an interface polymeric material, the rejection rate of the monovalent ions of the nanofiltration membrane is 10-50%, the rejection rate of the divalent and above valence ions of the nanofiltration membrane is 40-99%, and NaCl in the produced water of the nanofiltration membrane (dilute brine 6): 292g/L, Na2SO4：5.8g/L；
E) Monovalent ions in the produced water can be returned to the crystallization evaporation process to obtain a solid crystalline salt product or be sold as a liquid salt product with a specific concentration content;
F) divalent and above valence state ions in nanofiltration concentrated solution 10 of the nanofiltration membrane system are concentrated and can be returned to the production process, and products such as mirabilite and the like are recovered by a mother liquor recovery method or a freezing recovery method.
Example 2
A) The waste brine in the feed barrel 1 is tail water mother liquor in the salt making industry, the sodium chloride content of the waste brine is 290g/L, the sodium sulfate content is 28g/L, and Ca is added2+The content is 5Mg/L, Mg2+The content is 3.2mg/L, SS is 106mg/L, the waste brine is sent into a softening unit 2, sodium bicarbonate with the addition of 35mg/L is added into the softening unit 2 (reaction precipitation tank) filled with the waste brine through a dosing unit 7 under the stirring condition, then sodium hydroxide is added to adjust the pH value to 8.9, the stirring is continued for 15 minutes, so that scaling ions in the waste brine generate precipitation;
B) adding 6ppm polyacrylamide, stirring and settling for 18 minutes, aggregating suspended matters and generated precipitates in the waste brine into larger particles, settling to form precipitates, performing solid-liquid separation by a solid-liquid separation unit 3, treating solid precipitates 8 as wastes, and returning the separated liquid to the front-end step A);
C) in order to ensure the use effect of the key step of the subsequent membrane separation, the supernatant after the sedimentation step needs to be subjected to an ultrafiltration process, the supernatant enters an ultrafiltration unit 4 through a feed pump to further reduce small particles in water, an ultrafiltration concentrated solution 9 (an ultrafiltration backwashing concentrated solution) returns to the step B), the ultrafiltration unit 4 is a tubular ultrafiltration system, the aperture of a tubular membrane of the tubular ultrafiltration system is 1-0.01 μm, the operating pressure is 0.35MPa, and the NaCl content of the ultrafiltration product water: 290g/L, Na2SO4The content is as follows: 28g/L, Ca2+The content is as follows: 0.5Mg/L, Mg2+The content is as follows: 0.3mg/L, SS: 8 mg/L;
D) the softened and ultrafiltered waste brine is pressurized by a high-pressure pump and then is separated by a nanofiltration separation unit 5 (a special selective nanofiltration membrane), most of divalent and above valence ions are intercepted, the produced water mainly contains monovalent ions, the nanofiltration membrane of the nanofiltration membrane system is made of an interface polymeric material, the rejection rate of the monovalent ions of the nanofiltration membrane is 10-50%, the rejection rate of the divalent and above valence ions of the nanofiltration membrane is 40-99%, and NaCl in the produced water of the nanofiltration membrane (dilute brine 6): 298g/L, Na2SO4：1.8g/L；
E) Monovalent ions in the produced water can be returned to the crystallization evaporation process to obtain a solid crystalline salt product or be sold as a liquid salt product with a specific concentration content;
F) divalent and above valence state ions in nanofiltration concentrated solution 10 of the nanofiltration membrane system are concentrated and can be returned to the production process, and products such as mirabilite and the like are recovered by a mother liquor recovery method or a freezing recovery method.
In the embodiment 1-2, the softening unit 2 can be a reinforced concrete cement pool, or a carbon steel or glass fiber reinforced plastic pool, and comprises a stirrer or a gas stirrer; the sedimentation tank 3 can also be replaced by a guide cylinder, a honeycomb inclined plate, a filter, centrifugal separation and the like; the ultrafiltration unit 4 can be column type or tubular organic membrane ultrafiltration or inorganic ceramic membrane ultrafiltration; the nanofiltration separation unit 5 is an integrated device of low-pressure high-flux high-selectivity organic nanofiltration membranes which are imported as the Dow, Su-Ishi and Heiden energy or produced in China as Changfeng and Proxi; the medicine adding unit 7 is provided with a medicine dissolving barrel, a stirrer, a medicine adding pump and a pipeline.
In conclusion, by means of the technical scheme, impurity ions such as calcium and magnesium in the waste brine are reduced through chemical softening, particle impurities in the waste brine are removed through a filtering mode, then salt (sodium chloride) and nitrate (sodium sulfate) in the waste brine are separated and purified through membrane separation, the removal rate of sodium sulfate on a water production side is over 80%, the strong brine on the water production side after membrane separation can be sold as refined brine, and industrial high-purity sodium chloride can be recovered through processes such as evaporation crystallization.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (10)
1. The method for recovering salt and nitrate from the brine waste is characterized by comprising the following steps:
A) adding a softening agent into the waste brine containing impurities, suspended matters and scaling ions by a chemical softening method, and adjusting the pH value to enable the scaling ions in the waste brine to generate precipitates;
B) adding a proper amount of flocculation aid into softened waste brine, aggregating suspended matters and generated precipitates in the waste brine into particles, settling the particles to form precipitates, performing solid-liquid separation by a solid-liquid separation unit, treating the solid precipitates as wastes, and returning the separated liquid to the front-end step A);
C) the supernatant fluid after the sedimentation step is subjected to an ultrafiltration process to further reduce particles in the water, and the backwashing concentrated solution after the ultrafiltration is returned to the step B);
D) the softened and ultrafiltered waste brine enters a nanofiltration membrane system, divalent and above valence ions are intercepted, and the produced water contains monovalent ions;
E) monovalent ions in the produced water are returned to the crystallization evaporation process to obtain a solid crystalline salt product or sold as an industrial liquid salt product;
F) and (3) concentrating divalent and above valence ions in the concentrated solution of the nanofiltration membrane system, returning the concentrated solution to the production process, and recovering mirabilite by adopting a mother solution recovery or low-temperature freezing method.
2. The process of claim 1, wherein the TDS of the waste brine of step a) is 100-360g/L, wherein the TDS of monovalent salts is 100-300g/L and the TDS of divalent and higher salts is 10-60 g/L.
3. The method of claim 1, wherein the monovalent salt comprises: chlorides, bromides, iodides and nitrates of lithium, sodium and potassium.
4. The method of claim 1, wherein the divalent and higher salts comprise: sulfates, carbonates, phosphates of calcium, magnesium, iron, copper, zinc, chromium, manganese, cadmium.
5. The process of claim 1, wherein the spent brine in step a) has a sodium chloride content of 100 to 300g/L and a sodium sulfate content of 10 to 60 g/L.
6. The method of claim 1, wherein the source of the waste brine in step a) comprises: high-concentration tail water in the salt making industry, high-salinity wastewater in the nitrate making industry, mother liquor in salt making from seawater, mother liquor after salt extraction in salt lakes, near-saturated mother liquor after zero-discharge evaporation and crystallization of industrial wastewater and high-concentration salt water subjected to zero-discharge miscellaneous salt harmless treatment.
7. The method of claim 1, wherein the softening agent in step a) comprises one or more of caustic soda, sodium carbonate, sodium bicarbonate, and calcium hydroxide.
8. The method of claim 1, wherein the ultrafiltration membrane of the ultrafiltration process of step C) comprises an external pressure type hollow fiber membrane, a roll membrane, a tubular membrane, a ceramic membrane.
9. The method of claim 8, wherein the ultrafiltration membrane has a pore size of 1 to 0.01 μm.
10. The method as claimed in claim 1, wherein the nanofiltration membrane of the nanofiltration membrane system in step D) is an interfacial polymer material, the rejection rate of monovalent ions of the nanofiltration membrane is 10-50%, and the rejection rate of divalent and higher valence ions of the nanofiltration membrane is 40-99%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010036715.8A CN111170340A (en) | 2020-01-14 | 2020-01-14 | Method for recovering salt and nitrate from salt and nitrate waste brine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010036715.8A CN111170340A (en) | 2020-01-14 | 2020-01-14 | Method for recovering salt and nitrate from salt and nitrate waste brine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111170340A true CN111170340A (en) | 2020-05-19 |
Family
ID=70649420
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010036715.8A Pending CN111170340A (en) | 2020-01-14 | 2020-01-14 | Method for recovering salt and nitrate from salt and nitrate waste brine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111170340A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111960591A (en) * | 2020-07-17 | 2020-11-20 | 大连凯信石化科技有限公司 | Method for recycling PTA (purified terephthalic acid) oxidized tail gas washing wastewater |
| CN112456517A (en) * | 2020-12-08 | 2021-03-09 | 天津渤化永利化工股份有限公司 | Method for treating sulfate radical in salt washing brine of combined-alkali system by using nanofiltration membrane technology |
| CN113697987A (en) * | 2020-05-22 | 2021-11-26 | P2W有限公司 | Method and system for industrial wastewater treatment |
| CN115072753B (en) * | 2022-07-02 | 2023-05-19 | 山东海化集团有限公司 | Method for preparing magnesium sulfate heptahydrate and sodium chloride |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB0228351D0 (en) * | 2002-12-05 | 2003-01-08 | Altmann Thomas | Method for the production of sodium chloride from seawater |
| CN102627300A (en) * | 2012-04-20 | 2012-08-08 | 江苏凯米膜科技股份有限公司 | Double-membrane-method technology for refining brine and equipment for the same |
| CN105502782A (en) * | 2015-12-07 | 2016-04-20 | 湖南湘牛环保实业有限公司 | Technology for recovering water resources and salt from coking wastewater in coal chemical industry |
| CN107915360A (en) * | 2016-10-10 | 2018-04-17 | 北京朗新明环保科技有限公司 | Zero-emission crystallization divides salt device and technique |
| CN108773964A (en) * | 2018-06-15 | 2018-11-09 | 烟台金正环保科技有限公司 | A kind of zero-emission of high calcium waste water and method of resource |
-
2020
- 2020-01-14 CN CN202010036715.8A patent/CN111170340A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB0228351D0 (en) * | 2002-12-05 | 2003-01-08 | Altmann Thomas | Method for the production of sodium chloride from seawater |
| CN102627300A (en) * | 2012-04-20 | 2012-08-08 | 江苏凯米膜科技股份有限公司 | Double-membrane-method technology for refining brine and equipment for the same |
| CN105502782A (en) * | 2015-12-07 | 2016-04-20 | 湖南湘牛环保实业有限公司 | Technology for recovering water resources and salt from coking wastewater in coal chemical industry |
| CN107915360A (en) * | 2016-10-10 | 2018-04-17 | 北京朗新明环保科技有限公司 | Zero-emission crystallization divides salt device and technique |
| CN108773964A (en) * | 2018-06-15 | 2018-11-09 | 烟台金正环保科技有限公司 | A kind of zero-emission of high calcium waste water and method of resource |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113697987A (en) * | 2020-05-22 | 2021-11-26 | P2W有限公司 | Method and system for industrial wastewater treatment |
| CN113697987B (en) * | 2020-05-22 | 2022-09-06 | P2W有限公司 | Method and system for industrial wastewater treatment |
| CN111960591A (en) * | 2020-07-17 | 2020-11-20 | 大连凯信石化科技有限公司 | Method for recycling PTA (purified terephthalic acid) oxidized tail gas washing wastewater |
| CN112456517A (en) * | 2020-12-08 | 2021-03-09 | 天津渤化永利化工股份有限公司 | Method for treating sulfate radical in salt washing brine of combined-alkali system by using nanofiltration membrane technology |
| CN115072753B (en) * | 2022-07-02 | 2023-05-19 | 山东海化集团有限公司 | Method for preparing magnesium sulfate heptahydrate and sodium chloride |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111170340A (en) | Method for recovering salt and nitrate from salt and nitrate waste brine | |
| CN106746113B (en) | Process and system for recycling and reusing fluorine-containing wastewater in photovoltaic industry | |
| CN105439341B (en) | A kind of brine waste processing system and processing method | |
| CN112479467A (en) | Graphite wastewater treatment device and use method thereof | |
| CN107720782A (en) | A kind of technique and system for use in carrying for dividing salt preparing potassium sulfate from high-salt wastewater | |
| CN112142249B (en) | SO (SO)4·HCO3Method and system for treating and recycling-Na-type high-salt mine water | |
| CN105906128A (en) | Method and system for recovering sodium chloride from high salinity wastewater | |
| CN112707563A (en) | Membrane method recycling treatment device and treatment method for copper smelting high-salinity wastewater | |
| CN112299634A (en) | Method and device for improving quality of PTA high-salt wastewater evaporative crystallization salt separation | |
| CN111170519A (en) | Treatment process and treatment system for desulfurization wastewater | |
| CN111170516A (en) | Treatment process and treatment system for desulfurization wastewater | |
| CN106495187A (en) | Zero-discharge production process for refining liquid salt by double-membrane method | |
| CN109437444B (en) | Recycling treatment device and method for vanadium precipitation mother liquor and washing water | |
| CN111675394A (en) | High-salt industrial wastewater resource recovery treatment system and method | |
| CN103341321A (en) | Viscose sodium sulfate waste liquor acid and alkali recycling technology by virtue of bipolar membrane electrodialysis method | |
| CN111362480A (en) | Method for treating reverse osmosis strong brine | |
| CN205442916U (en) | Contain salt effluent disposal system | |
| CN113087259B (en) | Process for non-softening concentration of high-salt wastewater based on nanofiltration of recycled salt | |
| CN113698002A (en) | Novel reverse osmosis strong brine recovery treatment process | |
| CN113582410A (en) | Method for treating coal chemical industry wastewater | |
| CN110436679B (en) | Device and method for recycling and comprehensively utilizing washing water of lithium carbonate | |
| CN110668626A (en) | Chemical industry caustic soda device wastewater treatment process | |
| CN214936736U (en) | Salt dissolving system for seawater desalination concentrated seawater for chlor-alkali industry | |
| CN211111482U (en) | Lithium carbonate washing water resource comprehensive utilization's device | |
| CN106673290A (en) | Zero-discharge treatment process for crushed coal pressurized gasification wastewater |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200519 |
|
| RJ01 | Rejection of invention patent application after publication |