CN111392749A - Method for extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salinity wastewater in coal chemical industry in a quality-graded manner - Google Patents
Method for extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salinity wastewater in coal chemical industry in a quality-graded manner Download PDFInfo
- Publication number
- CN111392749A CN111392749A CN202010224100.8A CN202010224100A CN111392749A CN 111392749 A CN111392749 A CN 111392749A CN 202010224100 A CN202010224100 A CN 202010224100A CN 111392749 A CN111392749 A CN 111392749A
- Authority
- CN
- China
- Prior art keywords
- sodium chloride
- sodium sulfate
- nanofiltration
- purity
- wastewater
- 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
- C01D3/00—Halides of sodium, potassium or alkali metals in general
- C01D3/14—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
- C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
- C01D5/16—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
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
-
- 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
- C02F1/02—Treatment of water, waste water, or sewage by heating
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
- C02F1/041—Treatment of water, waste water, or sewage by heating by distillation or evaporation by means of vapour compression
-
- 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
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/283—Treatment of water, waste water, or sewage by sorption using coal, charred products, or inorganic mixtures containing them
-
- 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
- C02F1/441—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by reverse osmosis
-
- 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
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/725—Treatment of water, waste water, or sewage by oxidation by catalytic oxidation
-
- 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
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/78—Treatment of water, waste water, or sewage by oxidation with ozone
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A20/00—Water conservation; Efficient water supply; Efficient water use
- Y02A20/124—Water desalination
- Y02A20/131—Reverse-osmosis
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 relates to a method for separating and extracting salt from high-salt wastewater in coal chemical industry to obtain sodium sulfate and sodium chloride products, in particular to a method for separating and extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salt wastewater in coal chemical industry, which comprises the steps of sequentially carrying out decoloring, ultrafiltration membrane and wastewater concentration and separation on the high-salt wastewater generated in the coal chemical industry to obtain nanofiltration concentrated water which takes sodium sulfate as a main component and contains a small amount of sodium chloride and nanofiltration produced water which takes sodium chloride as a main component, concentrating the nanofiltration produced water by reverse osmosis, concentrating the nanofiltration produced water by a mechanical steam compression system to saturation, desalting and crystallizing to obtain sodium chloride products, and introducing desalting mother liquor into a nanofiltration device for separation; carrying out catalytic oxidation on nanofiltration concentrated water by ozone, and then introducing the nanofiltration concentrated water into a denitration thermal method crystallization device to obtain a sodium sulfate product; the method realizes the recycling of the high-salinity wastewater in the coal chemical industry and the separation of salt through the combination scheme of a membrane treatment technology, an ozone catalytic oxidation technology, a freezing crystallization and a thermal crystallization phase, and obtains industrial-grade sodium sulfate and sodium chloride products with the purity meeting the national standard.
Description
Technical Field
The invention relates to a method for separating and extracting salt from high-salt wastewater in coal chemical industry, which is generated in the coal-to-liquid process with complex components and high organic matter content, so as to obtain sodium sulfate and sodium chloride products, in particular to a method for separating and extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salt wastewater in coal chemical industry.
Background
The current energy structure of China is oil shortage and natural gas shortage, while the coal reserves are abundant and the coal price is low, and the energy structure enables the coal industry of China to be rapidly developed. The rapid development of the coal industry not only exerts the advantages of the coal resources in China, but also greatly supplements the petroleum and natural gas resources, thereby guaranteeing the energy safety problem in China and playing an important role in the field of sustainable development.
The opportunities arise with concomitant challenges. The rapid development of the coal industry is derived from two resource elements of coal and water, however, the development water consumption is huge, and the generation of high-salinity wastewater is a problem. Most of coal in China is mainly concentrated in northwest areas of Shanangan Ning and Xinjiang, but the coal is fragile in ecological environment and quite short in water resources, and only accounts for about 20% of the total reserves of water resources in China, so that the treatment of high-salinity wastewater in coal chemical industry and the recycling of water are very important.
With the enhancement of environmental protection and the deepening of sustainable development concept, the requirement of zero discharge of wastewater is higher and higher, however, at present, no method capable of solving the problems of low purity, low recovery rate, large proportion of miscellaneous salts and the like of sodium sulfate and sodium chloride crystal salts in a salt separation process provides a method for separating and extracting high purity and large particle sodium sulfate and sodium chloride from high-salt wastewater in coal chemical industry, realizing zero discharge of wastewater, separating and recovering salts, and improving economic, environmental and social benefits.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a method for extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salt wastewater in coal chemical industry by separating industrial-grade sodium sulfate and sodium chloride products with purity meeting national standards through a combined scheme of a membrane treatment technology, an ozone catalytic oxidation technology, a freezing crystallization and a thermal crystallization phase.
The invention is realized by the following modes:
a method for extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salinity wastewater in coal chemical industry by using a two-step method is characterized by comprising the following steps of: the method comprises the steps of sequentially passing high-salinity wastewater generated in the coal chemical industry process through a decolorization membrane, an ultrafiltration membrane and a wastewater concentration, then separating the concentrated high-salinity wastewater by using a nanofiltration membrane to obtain nanofiltration concentrated water which takes sodium sulfate as a main component and contains a small amount of sodium chloride and nanofiltration produced water which takes sodium chloride as a main component, concentrating the nanofiltration produced water which takes sodium chloride as a main component by reverse osmosis, concentrating the nanofiltration produced water to saturation by a mechanical steam compression system, desalting and crystallizing to obtain a sodium chloride product, and introducing a desalting mother liquor into a nanofiltration device again for separation; carrying out catalytic oxidation on nanofiltration concentrated water which takes sodium sulfate as a main component and contains a small amount of sodium chloride by ozone, and then introducing the nanofiltration concentrated water into a denitration thermal method crystallization device to obtain a sodium sulfate product;
separating the high-salinity wastewater subjected to reverse osmosis concentration by using a nanofiltration membrane under the conditions that the pressure is 1.5-1.7 MPa and the water inlet flow is 550-600L/h to obtain nanofiltration concentrated water which takes sodium sulfate as a main component and contains a small amount of sodium chloride and nanofiltration water production which takes sodium chloride as a main component, wherein the average rejection rate of the sodium sulfate in the nanofiltration process is 98-99%, and the average rejection rate of the sodium chloride is-4.2% -3.5%;
the obtained nanofiltration water product with sodium chloride as a main component is subjected to reverse osmosis concentration until TDS reaches 38-41 g/L, and then is concentrated to saturation by a mechanical vapor compression system, the saturated solution is directly desalted and crystallized, the stirring speed is controlled to be 180-220 r/min, the crystal growing time is controlled to be 50-70 min, a sodium chloride product with the purity of 98.5-99.5% and the particle size of 50-60 mu m is obtained, and the desalted mother liquor is reintroduced into the nanofiltration device for separation;
the obtained nanofiltration concentrated water mainly containing sodium sulfate and a small amount of sodium chloride has TDS of 58-64 g/L, COD is reduced to 100-150 mg/L through ozone catalytic oxidation, the water is introduced into a denitration thermal crystallization device, the corresponding evaporation temperature of 80-100 ℃, stirring rate of 180-220 r/min and crystal growth time of 80-100 min are controlled, a sodium sulfate product with purity of 98.0-99.5% and particle size of 200-250 mu m is obtained, the crystallization mother liquor is sent into a freezing device with temperature of-5-0 ℃, mirabilite crystals are obtained by reducing the temperature of the solution, the crystals are introduced into the previous procedure for dehydration to obtain an anhydrous sodium sulfate product, the denitration freezing mother liquor mainly contains sodium chloride and is sent into a subsequent desalting thermal crystallization device for crystallization to obtain a sodium chloride product, and the desalting mother liquor is transferred into a drying procedure for treatment, and finally the separation and recovery of sodium sulfate and sodium chloride salt in the high-salinity wastewater are realized;
the decoloring treatment adopts activated carbon decoloring treatment, and the wastewater concentration adopts a reverse osmosis membrane.
The invention has the following effects:
1) the method comprises the steps of firstly carrying out activated carbon decoloration treatment on high-salinity wastewater in the coal chemical industry, then removing suspended matters and macromolecular substances in the water through an ultrafiltration membrane, concentrating the high-salinity wastewater through reverse osmosis until the total soluble solids are 38-41 g/L, separating the wastewater through a nanofiltration membrane to obtain nanofiltration concentrated water mainly containing sodium sulfate and nanofiltration product water mainly containing sodium chloride, removing organic matters from the nanofiltration concentrated water through ozone catalytic oxidation, then carrying out cold and hot crystallization to obtain a sodium sulfate product with the purity of 98.0-99.5% and a small amount of sodium chloride product with the purity of 98.5-99.5%, concentrating the nanofiltration product water through reverse osmosis until the total soluble solids are 38-41 g/L, and then delivering the nanofiltration product water to a mechanical steam compression system for concentration, and obtaining a sodium chloride product with the purity of 98.5-99.5% after crystallization.
2) The operation is stable for a long time: the pretreatment technology in the method provided by the invention adopts an ultrafiltration technology, so that the long-term stable operation of a nanofiltration process is ensured, and a good salt separation effect is achieved.
3) The cost is low: the nanofiltration water production in the method provided by the invention adopts a reverse osmosis technology, the water production side is concentrated, the scale of the subsequent desalting thermal method crystallization is reduced, the cost is saved, and the operating cost of the whole device is also reduced.
4) The separation and recovery efficiency is high: the mother liquor obtained after the nanofiltration water production concentration and desalination is introduced into the nanofiltration salt separation system again, so that the yield of sodium sulfate and sodium chloride is improved, and the separation and recovery of salt in high-salinity wastewater to a greater extent are ensured; and moreover, the cold-hot combination method is adopted to treat the nanofiltration concentrated water, so that the influence of COD content on crystallization operation is reduced, the yield of sodium sulfate is improved, and the final discharge amount of mother liquor is reduced.
5) Improves the economic and social benefits and protects the environment: the sodium sulfate product with the purity meeting the first-class standard of GB/T6009-2014 II and the sodium chloride product with the purity meeting the first-class standard of GB/T5462-2016 refined industrial salt are obtained by the method provided by the invention, and the salt is separated and recovered on the basis of realizing zero discharge of wastewater, so that the economic and social benefits are improved, and the environment is protected.
Description of the drawings:
FIG. 1 is a process flow diagram of the process route operation of the present invention;
FIG. 2 is a diagram of the anhydrous sodium sulfate product obtained by the method of the present invention;
Detailed Description
Example 1 a method for mass extraction of high-purity and large-particle sodium sulfate and sodium chloride from high-salt wastewater of coal chemical industry, as shown in fig. 1, the high-salt wastewater generated in a coal oil production process is decolored by using activated carbon, suspended substances and macromolecular substances in the wastewater are removed by using an ultrafiltration membrane, the wastewater is concentrated to a TDS of 38.5 g/L by using a reverse osmosis membrane, nanofiltration membrane is used for the concentrated high-salt wastewater, the high-salt wastewater is separated under the conditions of a pressure of 1.58MPa and a water inlet flow of 570L/h to obtain nanofiltration concentrated water which takes sodium sulfate as a main component and contains a small amount of sodium chloride, nanofiltration product water which takes sodium chloride as a main component is produced by nanofiltration, the nanofiltration membrane is used for nanofiltration under a pressure of 1.58MPa, the sodium sulfate has an average rejection rate of 98.32% in the nanofiltration process, the sodium chloride has an average rejection rate of-3.75%, the nanofiltration product water which takes sodium chloride as a main component is concentrated by reverse osmosis to a TDS of 39.3 g/L, the TDS, the nanofiltration water is concentrated to a TDS, the sodium sulfate by a mechanical steam compression system, the desalination is directly desalted, the saturated solution is controlled by stirring speed of 190r/min, the ozone is controlled, the denitrification process, the nanofiltration process is carried out, the nanofiltration process is carried out on the nanofiltration membrane, the nanofiltration membrane is carried out on the nanofiltration membrane, the sodium sulfate concentrated product obtained, the sodium sulfate is carried out on the sodium sulfate concentrated water, the sodium sulfate concentrated water obtained, the sodium sulfate is carried out on the sodium sulfate concentrated water, the sodium sulfate concentrated water obtained, the sodium.
Example 2 a method for mass extraction of high-purity and large-particle sodium sulfate and sodium chloride from high-salt wastewater of coal chemical industry, as shown in fig. 1, the high-salt wastewater generated in the coal oil production process is decolored by using activated carbon, suspended substances and macromolecular substances in the wastewater are removed by using an ultrafiltration membrane, the wastewater is concentrated to have a TDS of 39.8 g/L by using a reverse osmosis membrane, nanofiltration concentrated water mainly containing sodium sulfate and a small amount of sodium chloride and nanofiltration product water mainly containing sodium chloride are obtained by separating the high-salt wastewater under the conditions of a pressure of 1.65MPa and a water inlet flow rate of 560L/h, sodium sulfate is concentrated to have a mean retention rate of 39.8 g/L% in the nanofiltration process, sodium sulfate is concentrated to have a mean retention rate of 39.8 g/L in the nanofiltration process, sodium sulfate is concentrated to have a mean retention rate of 98.48% in the nanofiltration process, sodium chloride is concentrated to have a TDS of 39.8 g/L in the nanofiltration process, sodium sulfate is concentrated to be subjected to a TDS concentration by using a mechanical steam compression system, the sodium sulfate is directly desalted, the saturated solution, the ozone-maintaining rate of 200r/min, the denitrification process is carried out ozone-crystallization process, the denitrification, the nanofiltration process is carried out the nanofiltration process, the nanofiltration process is carried out the nanofiltration process, the process is carried out the process, the process is carried out the process, the process is carried out the process, the process is carried out the.
Embodiment 3. a method for mass extraction of high-purity and large-particle sodium sulfate and sodium chloride from high-salt wastewater of coal chemical industry, as shown in fig. 1, the method comprises the steps of decolorizing high-salt wastewater generated in a coal oil production process by using activated carbon, removing suspended substances and macromolecular substances in the wastewater by using an ultrafiltration membrane, concentrating the wastewater by using a reverse osmosis membrane until the TDS is 40.53 g/L. nanofiltration wastewater for concentrated high-salt wastewater is separated under the conditions of 1.70MPa pressure and 580L/h water inflow, to obtain nanofiltration concentrated water which takes sodium sulfate as a main component and contains a small amount of sodium chloride, and nanofiltration product water which takes sodium chloride as a main component, concentrating the nanofiltration product water which takes sodium sulfate as a main component by using a reverse osmosis system until the TDS reaches 40.26 g/L. the nanofiltration product water which takes sodium chloride as a main component, concentrating the nanofiltration product water which takes sodium chloride as a main component by using a mechanical steam compression system until the TDS is saturated and crystallized, controlling the average retention rate of sodium sulfate/crystal growth, the ozone crystallization time r/min, the ozone crystallization time r/crystallization time r is 210 min, the ozone concentration time r, the nanofiltration product is 65min, introducing the nanofiltration concentrate liquid into a nanofiltration concentrate liquid which takes sodium chloride as a sodium sulfate concentrate, introducing the sodium chloride concentrate into a sodium chloride concentrate, introducing the sodium sulfate concentrate into a sodium sulfate concentrate, and sodium chloride concentrate into a sodium sulfate concentrate, introducing the sodium sulfate concentrate, and a sodium chloride concentrate, and a sodium sulfate concentrate, introducing the sodium sulfate concentrate, and a sodium chloride concentrate, introducing the sodium chloride concentrate, and a sodium sulfate concentrate into a sodium sulfate concentrate, wherein the sodium sulfate concentrate, and a sodium sulfate concentrate, wherein the sodium sulfate concentrate.
Embodiment 4A method for extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salt wastewater in coal chemical industry by mass spectrometry comprises the steps of as shown in FIG. 1, decolorizing the high-salt wastewater generated in the coal oil production process by using activated carbon, removing suspended matters and macromolecular substances in the wastewater by using an ultrafiltration membrane, concentrating the wastewater by using a reverse osmosis membrane until the TDS is 39.82 g/L, separating the high-salt wastewater by using a nanofiltration membrane under the conditions of a pressure of 1.65MPa and a water inlet flow rate of 590L/h to obtain nanofiltration concentrated water which takes sodium sulfate as a main component and contains a small amount of sodium chloride, and nanofiltration product water which takes sodium chloride as a main component, concentrating the nanofiltration product water which takes sodium chloride as a main component by using reverse osmosis until the TDS reaches 39.85 g/L, concentrating the nanofiltration product water which takes sodium sulfate as a main component by using a mechanical steam compression system until the sodium sulfate is saturated, directly desalinating the sodium sulfate, controlling the stirring speed of 200r/min, the crystal growth time of 60min, introducing the nanofiltration product water into a nanofiltration concentrated water which takes sodium chloride as a sodium chloride solution containing sodium chloride as a sodium sulfate, introducing the sodium chloride into a nanofiltration concentrate, introducing the nanofiltration concentrate liquid which takes sodium chloride as a sodium sulfate, and a sodium chloride crystal drying process to obtain a sodium sulfate crystallization mother liquor which takes sodium sulfate as a sodium sulfate crystallization mother liquor which takes sodium sulfate crystal with a sodium sulfate crystallization mother liquor which has an average desalination temperature of 75.90 min, introducing the sodium sulfate crystallization mother liquor which is 70.90 mg, introducing the sodium sulfate crystallization mother liquor which is reduced by using a denitrification process of a denitrification process, introducing a denitrification process of 80 mm, introducing a denitrification process of 80-90 min, introducing a denitrification process of a.
FIG. 2 is a diagram of the anhydrous sodium sulfate product obtained by the method of the present invention.
Claims (5)
1. A method for extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salinity wastewater in coal chemical industry by using a two-step method is characterized by comprising the following steps of: firstly, high-salinity wastewater is sequentially subjected to decolorization, ultrafiltration membrane and wastewater concentration, then a nanofiltration membrane is used for separation to obtain nanofiltration concentrated water which takes sodium sulfate as a main component and contains a small amount of sodium chloride and nanofiltration produced water which takes sodium chloride as a main component, then the nanofiltration produced water which takes sodium chloride as a main component is subjected to reverse osmosis concentration, then the nanofiltration produced water is concentrated to saturation through a mechanical steam compression system, and a sodium chloride product is obtained after desalination and crystallization, and a desalination mother liquor is introduced into the nanofiltration membrane again for separation; the nanofiltration concentrated water which takes sodium sulfate as a main component and contains a small amount of sodium chloride is subjected to catalytic oxidation by ozone and then is introduced into a denitration thermal crystallization device to obtain a sodium sulfate product.
2. The method for separating and extracting the high-purity and large-particle sodium sulfate and the sodium chloride from the high-salinity wastewater in the coal chemical industry according to claim 1, wherein the pressure for separating the sodium sulfate and the sodium chloride by the nanofiltration membrane is 1.5-1.7 MPa, the water inflow rate is 550-600L/h, the average retention rate of the sodium sulfate in the nanofiltration process is 98-99%, and the average retention rate of the sodium chloride is-4.2% -3.5%.
3. The method for extracting the high-purity and large-particle sodium sulfate and sodium chloride from the high-salinity wastewater in the coal chemical industry according to the claim 1 or 2, which is characterized in that the obtained nanofiltration water product taking the sodium chloride as the main component is concentrated to TDS of 38-41 g/L through reverse osmosis, then concentrated to saturation through a mechanical vapor compression system, the saturated solution is directly desalted and crystallized, and the sodium chloride product with the purity of 98.5% -99.5% and the particle size of 50-60 μm can be obtained by controlling the stirring speed of 180-220 r/min and the crystal growing time of 50-70 min during desalting and crystallization.
4. The method for extracting the high-purity and large-particle sodium sulfate and sodium chloride from the high-salinity wastewater in the coal chemical industry according to the claim 1 or 2 is characterized in that the TDS of the obtained nanofiltration concentrated water mainly containing sodium sulfate and a small amount of sodium chloride is 58-64 g/L, COD is reduced to 100-150 mg/L through catalytic oxidation of ozone, the obtained water is introduced into a denitration thermal crystallization device, the evaporation temperature is controlled to be 80-100 ℃, the stirring speed is controlled to be 180-220 r/min, the crystal growing time is 80-100 min, a sodium sulfate product with the purity of 98.0-99.5% and the particle size of 200-250 μm is obtained, the crystallization mother liquor is sent into a freezing device with the temperature of-5-0 ℃, mirabilite crystals are obtained through reducing the temperature of the solution, the mirabilite crystals are introduced into the previous procedure for dehydration to obtain an anhydrous sodium sulfate product, the denitration frozen mother liquor mainly contains sodium chloride, the sodium chloride is sent into a subsequent desalting thermal crystallization device for crystallization to obtain a sodium chloride product, the desalting mother liquor is treated, and the dried sodium chloride wastewater with the high-purity and sodium chloride is finally recovered.
5. The method for extracting the high-purity and large-particle sodium sulfate and the sodium chloride from the high-salinity wastewater of the coal chemical industry according to claim 1, which comprises the following steps: the decoloring treatment adopts activated carbon decoloring treatment, and the wastewater concentration adopts a reverse osmosis membrane.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010224100.8A CN111392749A (en) | 2020-03-26 | 2020-03-26 | Method for extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salinity wastewater in coal chemical industry in a quality-graded manner |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010224100.8A CN111392749A (en) | 2020-03-26 | 2020-03-26 | Method for extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salinity wastewater in coal chemical industry in a quality-graded manner |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111392749A true CN111392749A (en) | 2020-07-10 |
Family
ID=71424930
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010224100.8A Pending CN111392749A (en) | 2020-03-26 | 2020-03-26 | Method for extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salinity wastewater in coal chemical industry in a quality-graded manner |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111392749A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113912231A (en) * | 2021-07-13 | 2022-01-11 | 北京航天环境工程有限公司 | System and method for recycling and co-processing wastewater |
| CN114426479A (en) * | 2020-10-10 | 2022-05-03 | 中国石油化工股份有限公司 | Method and device for refining long-chain dicarboxylic acid |
| CN114751573A (en) * | 2022-04-11 | 2022-07-15 | 宁夏大学 | Method for separating mass crystallization and salt extraction from high-salt wastewater in coal chemical industry |
| CN115259542A (en) * | 2022-06-11 | 2022-11-01 | 宁夏中科生物新材料有限公司 | Method for recycling long-chain dicarboxylic acid high-salinity wastewater |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106116002A (en) * | 2016-08-03 | 2016-11-16 | 东华工程科技股份有限公司 | A kind of extract sodium sulfate in high purity and the method for sodium chloride product in Coal Chemical Industry high slat-containing wastewater |
| CN107619144A (en) * | 2017-10-20 | 2018-01-23 | 侯新春 | A kind of high slat-containing wastewater divides salt process for reclaiming and system |
-
2020
- 2020-03-26 CN CN202010224100.8A patent/CN111392749A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106116002A (en) * | 2016-08-03 | 2016-11-16 | 东华工程科技股份有限公司 | A kind of extract sodium sulfate in high purity and the method for sodium chloride product in Coal Chemical Industry high slat-containing wastewater |
| CN107619144A (en) * | 2017-10-20 | 2018-01-23 | 侯新春 | A kind of high slat-containing wastewater divides salt process for reclaiming and system |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114426479A (en) * | 2020-10-10 | 2022-05-03 | 中国石油化工股份有限公司 | Method and device for refining long-chain dicarboxylic acid |
| CN113912231A (en) * | 2021-07-13 | 2022-01-11 | 北京航天环境工程有限公司 | System and method for recycling and co-processing wastewater |
| CN113912231B (en) * | 2021-07-13 | 2023-09-26 | 北京航天环境工程有限公司 | System and method for resource co-processing of wastewater |
| CN114751573A (en) * | 2022-04-11 | 2022-07-15 | 宁夏大学 | Method for separating mass crystallization and salt extraction from high-salt wastewater in coal chemical industry |
| CN115259542A (en) * | 2022-06-11 | 2022-11-01 | 宁夏中科生物新材料有限公司 | Method for recycling long-chain dicarboxylic acid high-salinity wastewater |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111392749A (en) | Method for extracting high-purity and large-particle sodium sulfate and sodium chloride from high-salinity wastewater in coal chemical industry in a quality-graded manner | |
| CN111484178B (en) | Comprehensive treatment method for seawater or strong brine | |
| US9133229B2 (en) | Economic process for producing xylose from hydrolysate using electrodialysis and direct recovery method | |
| CN103539281B (en) | White carbon black production wastewater treatment technology | |
| CN107265734B (en) | Reverse osmosis concentrated seawater treatment system and method | |
| CN108658345B (en) | Method and system for refining salt from high-salt wastewater | |
| US11219863B2 (en) | Method for separation and enrichment of lithium | |
| CN106830010B (en) | Methanol and ammonium chloride extraction equipment and extraction process in glycine production | |
| CN101812009A (en) | Novel technique for extracting L-tryptophan from fermentation broth | |
| CN106082516B (en) | Salt separation crystallization process and device | |
| CN111252975A (en) | High-salinity organic wastewater resourceful treatment process and system based on supercritical water oxidation | |
| CN111252974A (en) | Process and system for treating high-salinity organic wastewater based on supercritical water oxidation | |
| CN102977163A (en) | Industrialized preparation method of stevioside | |
| CN112299613A (en) | Zero-emission process system for sewage treatment | |
| CN101177741A (en) | Method for producing 4N metal gallium | |
| CN114031097B (en) | Separation and purification technology of potassium salt extracting solution obtained by extracting potassium from corn soaking solution | |
| CN102229521B (en) | Process for refining crude glycerin and recovering byproducts | |
| CN106588641B (en) | A kind of recovery method of 2-KLG primary crystallization mother liquor | |
| CN112047401B (en) | Method for thickening and refining seawater by using sodium sulfate | |
| CN104086409A (en) | Process for producing gluconic acid by bipolar membrane electrodialysis method | |
| CN108996521B (en) | Process for producing high-purity refined salt by using selective electrodialysis concentrated brine | |
| CN110527752B (en) | Electrodialysis separation process of hemicellulose hydrolysate | |
| CN113023990A (en) | Method for treating high-salinity water in steel plant | |
| JP6084198B2 (en) | Economic process for the production of xylose from saccharified liquid using electrodialysis and direct recovery methods | |
| CN215517040U (en) | High organic matter processing apparatus that contains salt |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200710 |