CN114315039A

CN114315039A - High salt effluent disposal system

Info

Publication number: CN114315039A
Application number: CN202111667866.4A
Authority: CN
Inventors: 曹镇海; 朱雄军; 杨宝军; 祝贵威; 张廷德
Original assignee: Ordos Haohua Guotai Chemical Co Ltd
Current assignee: Ordos Haohua Guotai Chemical Co Ltd
Priority date: 2021-12-31
Filing date: 2021-12-31
Publication date: 2022-04-12
Anticipated expiration: 2041-12-31
Also published as: CN114315039B

Abstract

The invention discloses a high-salinity wastewater treatment system which comprises a gasified ash water source, a domestic sewage source, a desalted water and sewage source, a circulating water and sewage source, other sewage sources, a gasification high-density unit, a biochemical treatment unit, a softened water treatment unit, a deep treatment unit, a concentration crystallization unit and a reuse water tank. Has the advantages that: according to the difference of the treated water quality, the gasified grey water and the domestic sewage are treated, and then the desalted water sewage, the circulating water sewage and other sewage are introduced, so that the treatment capacity of the previous equipment and the volume of the equipment can be reduced, and the investment and the occupied area of the equipment are further reduced; by back flushing the equipment, the running period of the equipment can be prolonged, and the long-time stable running of the system is ensured; the water resource and the industrial salt are effectively recycled, and the resource recycling is realized.

Description

High salt effluent disposal system

The technical field is as follows:

the invention relates to the field of water treatment, in particular to a high-salinity wastewater treatment system.

Background art:

during the production of methanol from coal, a large amount of biochemical grey water (about 90 m) is produced³H) and simultaneously, a large amount of domestic sewage (about 10 m) is generated in the normal operation process of the chemical plant³H) and desalted water sewage (about 140 m)³Perh) and sewage discharged from circulating water station (about 20 m)³H) and other effluents (about 30 m)³H); because the pollutants in the sewage are of various types, such as total salt, COD, sulfide, ammonia nitrogen, suspended matters and the like, the biodegradability is poor, and the treatment is difficult. At present, most enterprises have low wastewater treatment technical level and worse clean production level, and a series of stricter wastewater discharge standards recently issued by the national environmental protection ministry make the enterprises more difficult to ensure that the discharged wastewater reaches the standard. Therefore, for the enterprises to survive and develop, clean production and transformation are required to be implemented and new efficient, practical and low-cost sewage treatment technology is adopted.

Wastewater treatment methods can be divided into four major categories according to their effects, namely: physical treatment, chemical treatment, physicochemical and biological treatment. Biological treatment and physical and chemical methods are currently used. The biological treatment technology commonly adopts methods such as an anaerobic biological treatment method, an activated sludge method, a biofilm method and an oxidation pond method. The physical chemical treatment method is a method for purifying waste water by using a combination of physical and chemical actions. The method is a wastewater treatment system consisting of a physical method and a chemical method, or a single treatment method comprising a physical process and a chemical process. However, for the coal-to-methanol wastewater with complex components, the following problems often exist by using the conventional water treatment technology: 1. the water resource can not realize higher recovery rate, thus causing the waste of the water resource; 2. the equipment has short operation period and cannot stably operate for a long time; 3. the effective resources can not be recycled; 4. the equipment has large volume, large occupied area and high investment cost.

The invention content is as follows:

the invention aims to provide a high-salinity wastewater treatment system.

The invention is implemented by the following technical scheme:

a high-salinity wastewater treatment system comprises a gasified grey water source, a domestic sewage source, a desalted water and sewage source, a circulating water and sewage source, other sewage sources, a gasification high-density unit, a biochemical treatment unit, a softened water treatment unit, a deep treatment unit, a concentration crystallization unit and a reuse water tank;

the water outlet of the gasified grey water source and the water outlet of the domestic sewage source are communicated with the water inlet of the first regulating tank of the gasification high-density unit through pipelines, the supernatant outlet of the first sedimentation tank of the gasification high-density unit is communicated with the water inlet of the second regulating tank of the biochemical treatment unit through pipelines, the water outlet of the biological aerated filter of the biochemical treatment unit is communicated with the water inlet of the third regulating tank of the sewage softening unit of the softened water treatment unit through pipelines, the water outlet of the third sedimentation tank of the second-stage softening unit of the sewage softening unit, the water outlet of the third sedimentation tank of the second-stage softening unit of the nanofiltration concentrated water softening unit of the softened water treatment unit, the water outlet of the desalted water sewage source, the water outlet of the circulating water sewage source and the water outlets of other sewage sources are communicated with the water inlet of the fourth regulating tank of the advanced treatment unit through pipelines, the delivery port of advanced treatment unit's high salt water pond pass through the pipeline with softened water treatment unit's the water inlet intercommunication of the third equalizing basin of receiving thick water softening unit of straining, the product water export of advanced treatment unit's RO device and the product water export of thick water RO device all through the pipeline with the water inlet intercommunication of reuse water pond, the delivery port in advanced treatment unit's high concentration pond pass through the pipeline with the water inlet intercommunication of the fifth equalizing basin of concentrated treatment unit, the thick water export of concentrated treatment unit's thick water reverse osmosis unit pass through the pipeline with the water inlet intercommunication of the sixth equalizing basin of concentrated crystallization unit, the delivery port of concentrated crystallization unit's deaminizing resin bed with the water inlet intercommunication of reuse water pond.

Further, the gasification high-density unit comprises a first regulating tank, a first reaction tank, a first coagulation tank, a first flocculation tank, a first sedimentation tank, a first sludge concentration tank and a first filter press;

the water outlet of the first regulating tank is communicated with the water inlet of the first reaction tank through a pipeline, the water outlet of the first reaction tank is communicated with the inlet of the first coagulation tank through a pipeline, the outlet of the first coagulation tank is communicated with the water inlet of the first flocculation tank through a pipeline, the water outlet of the first flocculation tank is communicated with the water inlet of the first sedimentation tank through a pipeline, the sludge outlet of the first sedimentation tank is divided into two paths, one path is communicated with the inlet of the first coagulation tank through a pipeline, the other path is communicated with the inlet of the first sludge concentration tank through a pipeline, the sludge outlet of the first sludge concentration tank is communicated with the inlet of the first filter press through a pipeline, and the supernatant outlet of the first sludge concentration tank and the supernatant outlet of the first filter press are communicated with the water inlet of the first regulating tank through pipelines.

Further, the biochemical treatment unit comprises a second adjusting tank, an air floatation tank, a biochemical tank, a biological aeration filter tank, a second sludge concentration tank and a second filter press;

the water outlet of the second adjusting tank is communicated with the water inlet of the air floatation tank through a pipeline, the water outlet of the air floatation tank is communicated with the water inlet of the biochemical tank through a pipeline, the water outlet of the biochemical tank is communicated with the water inlet of the biological aerated filter tank through a pipeline, the sludge outlet of the biochemical tank is communicated with the inlet of the second sludge concentration tank through a pipeline, the sludge outlet of the second sludge concentration tank is communicated with the inlet of the second filter press through a pipeline, and the supernatant outlets of the second sludge concentration tank and the second filter press are communicated with the inlet of the second adjusting tank through pipelines.

Further, the softened water treatment unit comprises a sewage softening unit and a nanofiltration concentrated water softening unit;

the sewage softening unit and the nanofiltration concentrated water softening unit have the same structure and respectively comprise a third regulating tank, a primary softening unit, a secondary softening unit, a third sludge concentration tank and a third filter press;

the primary softening unit and the secondary softening unit respectively comprise a coagulation tank A, a coagulation tank B, a third flocculation tank and a third sedimentation tank which are sequentially connected in series;

a water outlet of the third regulating tank is communicated with a water inlet of the coagulation tank A of the primary softening unit through a pipeline, and a supernatant outlet of a third sedimentation tank of the primary softening unit is communicated with a water inlet of the coagulation tank A of the secondary softening unit through a pipeline; the sludge outlet of the third sedimentation tank of the primary softening unit is divided into three paths, wherein the two paths are respectively communicated with the coagulation tank A and the coagulation tank B of the primary softening unit through pipelines, and the third path is communicated with the inlet of the third sludge concentration tank through a pipeline; a sludge outlet of a third sedimentation tank of the second-stage softening unit is divided into three paths, wherein the two paths are respectively communicated with a coagulation tank A and a coagulation tank B of the second-stage softening unit through pipelines, and the third path is communicated with an inlet of a third sludge concentration tank through a pipeline;

and a sludge outlet of the third sludge concentration tank is communicated with an inlet of the third filter press through a pipeline, and a supernatant outlet of the third sludge concentration tank and a supernatant outlet of the third filter press are communicated with a water inlet of the third regulating tank through pipelines.

Further, the advanced treatment unit comprises a fourth regulating tank, a mechanical clarification tank, a fourth sludge concentration tank, a fourth filter press, an intermediate water tank, a multi-media filter, a self-cleaning filter, an ultrafiltration device, an ultrafiltration water tank, a nanofiltration cartridge filter, a nanofiltration device, a nanofiltration water tank, a high-salinity water tank, an RO cartridge filter, an RO device, an RO concentrate tank, a RO cartridge filter, a concentrate RO device and a high-concentration water tank;

the water outlet of the fourth regulating reservoir is communicated with the water inlet of the mechanical clarification tank through a pipeline, the sludge outlet of the mechanical clarification tank is communicated with the inlet of the fourth sludge concentration tank through a pipeline, the sludge outlet of the sludge concentration tank is communicated with the inlet of the fourth filter press through a pipeline, and the supernatant outlets of the fourth sludge concentration tank and the fourth filter press are communicated with the water inlet of the fourth regulating reservoir through pipelines; the supernatant outlet of the mechanical clarification tank is communicated with the water inlet of the middle water tank through a pipeline, the water outlet of the middle water tank is communicated with the water inlet of the multi-medium filter through a pipeline, the water outlet of the multi-medium filter is communicated with the water inlet of the self-cleaning filter through a pipeline, the water outlet of the self-cleaning filter is communicated with the water inlet of the ultrafiltration device through a pipeline, the water outlet of the ultrafiltration device is communicated with the water inlet of the ultrafiltration water tank through a pipeline, the water outlet of the ultrafiltration water tank is communicated with the water inlet of the nanofiltration safety filter through a pipeline, the water outlet of the nanofiltration safety filter is communicated with the water inlet of the nanofiltration device through a pipeline, the concentrated water outlet of the nanofiltration device is communicated with the water inlet of the high-salt water tank through a pipeline, and the water outlet of the nanofiltration device is communicated with the water inlet of the nanofiltration water tank through a pipeline, the water outlet of the nanofiltration water tank is communicated with the water inlet of the RO security filter through a pipeline, the water outlet of the RO security filter is communicated with the water inlet of the RO device through a pipeline, the concentrated water outlet of the RO device is communicated with the water inlet of the RO concentrated water tank through a pipeline, the water outlet of the RO concentrated water tank is communicated with the water inlet of the concentrated water RO security filter through a pipeline, the water outlet of the concentrated water RO security filter is communicated with the water inlet of the concentrated water RO device through a pipeline, and the concentrated water outlet of the concentrated water RO device is communicated with the water inlet of the concentrated water tank through a pipeline.

Furthermore, the concentration treatment unit comprises a fifth regulating tank, a multi-medium filtering device, a filtering water producing tank, a first-stage ion exchange device, a decarbonizer, a first intermediate water tank, a first-stage reverse osmosis device, a reverse osmosis water producing tank, a second intermediate water tank, a concentrated water ion exchange device, a third intermediate water tank and a concentrated water reverse osmosis device;

the water outlet of the fifth regulating tank is communicated with the water inlet of the multi-medium filtering device through a pipeline, the water outlet of the multi-medium filtering device is communicated with the water inlet of the filtering water producing tank through a pipeline, the water outlet of the filtering water producing tank is communicated with the water inlet of the first-stage ion exchange device through a pipeline, the water outlet of the first-stage ion exchange device is communicated with the water inlet of the decarbonizer through a pipeline, the water outlet of the decarbonizer is communicated with the water inlet of the first intermediate water tank through a pipeline, the water outlet of the first intermediate water tank is communicated with the water inlet of the first-stage reverse osmosis device through a pipeline, the water producing outlet of the first-stage reverse osmosis device is communicated with the water inlet of the reverse osmosis water producing tank through a pipeline, and the concentrated water outlet of the first-stage reverse osmosis device is communicated with the water inlet of the second intermediate water tank through a pipeline, the water outlet of the second middle water tank is communicated with the water inlet of the concentrated water ion exchange device through a pipeline, the water outlet of the concentrated water ion exchange device is communicated with the water inlet of the third middle water tank through a pipeline, and the water outlet of the third middle water tank is communicated with the water inlet of the concentrated water reverse osmosis device through a pipeline.

Further, the concentration and crystallization unit comprises a sixth regulating reservoir, a primary precipitation device, an ammonia stripping device, a secondary precipitation device, a precipitation product water tank, a first sand filtration device, an ultrafilter, an ultrafiltration product water tank, a chelate resin bed, a resin product water tank, an organic concentration device, a nanofilter, a sodium sulfate buffer tank, a sodium sulfate freezing and crystallization device, a sodium sulfate hot melting and evaporation device, a sodium sulfate centrifugal drying device, a nanofiltration product water tank, a primary RO device, an RO concentrated water tank, an ozone oxidation device, a sodium chloride evaporation water tank, a sodium chloride multiple-effect evaporation water tank, a sodium chloride centrifugal drying device, a mixed salt evaporation and crystallization device, a mixed salt device, a secondary RO water inlet regulating reservoir, a secondary RO device and a deamination resin bed;

the water outlet of the sixth regulating tank is communicated with the water inlet of the primary sedimentation device through a pipeline, the supernatant outlet of the primary sedimentation device is communicated with the water inlet of the ammonia stripping device through a pipeline, the water outlet of the ammonia stripping device is communicated with the water inlet of the secondary sedimentation device through a pipeline, the supernatant outlet of the secondary sedimentation device is communicated with the water inlet of the sedimentation product water tank through a pipeline, the water outlet of the sedimentation product water tank is communicated with the water inlet of the first sand filtration device through a pipeline, the water outlet of the first sand filtration device is communicated with the water inlet of the ultrafilter through a pipeline, the water outlet of the ultrafilter is communicated with the water inlet of the ultrafiltration product water tank through a pipeline, the water outlet of the ultrafiltration product water tank is communicated with the water inlet of the chelate resin bed through a pipeline, and the water outlet of the chelate resin bed is communicated with the water inlet of the resin product water tank through a pipeline, the water outlet of the resin water producing tank is communicated with the water inlet of the organic concentration device through a pipeline, the water producing outlet of the organic concentration device is communicated with the water inlet of the sodium filter through a pipeline, the concentrated water outlet of the sodium filter is communicated with the water inlet of the sodium sulfate buffer tank through a pipeline, the water outlet of the sodium sulfate buffer tank is communicated with the water inlet of the sodium sulfate freezing and crystallizing device through a pipeline, the crystal slurry outlet of the sodium sulfate freezing and crystallizing device is communicated with the inlet of the sodium sulfate hot melting and evaporating device through a pipeline, and the outlet of the sodium sulfate hot melting and evaporating device is communicated with the inlet of the sodium sulfate centrifugal drying device through a pipeline;

the water outlet of the nano filter is communicated with the water inlet of the nano filtration water production tank through a pipeline, the water outlet of the nano filtration water production tank is communicated with the water inlet of the primary RO device through a pipeline, the water outlet of the primary RO device is communicated with the water inlet of the secondary RO water inlet regulating tank through a pipeline, the water outlet of the secondary RO water inlet regulating tank is communicated with the water inlet of the secondary RO device through a pipeline, and the water outlet of the secondary RO device is communicated with the water inlet of the deamination resin bed through a pipeline; the concentrated water outlet of the first-stage RO device is communicated with the water inlet of the RO concentrated water tank through a pipeline, the water outlet of the RO concentrated water tank is communicated with the water inlet of the ozone oxidation device through a pipeline, the water outlet of the ozone oxidation device is communicated with the water inlet of the sodium chloride evaporation water tank through a pipeline, the water outlet of the sodium chloride evaporation water tank is communicated with the water inlet of the sodium chloride multi-effect evaporation crystallizer through a pipeline, the crystal slurry outlet of the sodium chloride multi-effect evaporation crystallizer is communicated with the inlet of the sodium chloride centrifugal drying device through a pipeline, the mother liquor outlet of the sodium chloride multi-effect evaporation crystallizer and the concentrated water outlet of the organic concentration device are communicated with the inlet of the mixed salt evaporation crystallization device through pipelines, the outlet of the mixed salt evaporation crystallization device and the mother liquor outlet of the sodium sulfate freezing crystallization device are communicated with the inlet of the mixed salt drying device through pipelines.

Furthermore, the water outlet of the filtering water generating tank is divided into two paths, one path is communicated with a flushing water inlet of the multi-medium filtering device through a pipeline, and the other path is communicated with a flushing water inlet of the primary ion exchange device through a pipeline; the water outlet of the reverse osmosis water production tank is communicated with the flushing water inlet of the first-stage reverse osmosis device through a pipeline; the water outlet of the second intermediate water tank is also communicated with a flushing water inlet of the concentrated water ion exchange device through a pipeline;

the outlet of the flushing water of the multi-medium filtering device, the outlet of the flushing water of the primary ion exchange device, the outlet of the flushing water of the primary reverse osmosis device and the outlet of the flushing water of the concentrated water ion exchange device are communicated with the water inlet of the wastewater collecting tank through pipelines, and the water outlet of the wastewater collecting tank is communicated with the water inlet of the fifth regulating tank through a pipeline.

The invention has the advantages that:

according to the difference of the treated water quality, the gasified grey water and the domestic sewage are treated, and then the desalted water sewage, the circulating water sewage and other sewage are introduced, so that the treatment capacity of the previous equipment and the volume of the equipment can be reduced, and the investment and the occupied area of the equipment are further reduced; by back flushing the equipment, the running period of the equipment can be prolonged, and the long-time stable running of the system is ensured; the water resource and the industrial salt are effectively recycled, and the resource recycling is realized.

The device is reasonable in configuration, can effectively reduce the discharge of sewage, and improves the utilization rate of resources. The method conforms to the national 'clean production promotion law', energy conservation, consumption reduction, environmental protection and other industrial policies and basic national policy. The production technology reaches the domestic and advanced level. Can more effectively utilize sewage cycle utilization rate, effectively promote the discarded object utilization efficiency of enterprise, reduce the environmental protection risk, promote the guarantee of company's profit.

Description of the drawings:

in order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of the system connection of a gasification high-density unit according to the present invention;

FIG. 2 is a schematic view of the system connection of the biochemical processing unit according to the present invention;

FIG. 3 is a schematic diagram of the system connections of the demineralized water treatment unit of the present invention;

FIG. 4 is a schematic diagram of the system connection of the deep processing unit of the present invention;

FIG. 5 is a schematic diagram of the system connection of the concentration unit according to the present invention;

FIG. 6 is a schematic diagram of the system connection of the concentration and crystallization unit according to the present invention.

In the figure: a gasification high-density unit 1, a first adjusting tank 101, a first reaction tank 102, a first coagulation tank 103, a first flocculation tank 104, a first sedimentation tank 105, a first sludge concentration tank 106, a first filter press 107, a biochemical treatment unit 2, a second adjusting tank 201, an air flotation tank 202, a biochemical tank 203, a biological aerated filter 204, a second sludge concentration tank 205, a second filter press 206, a softened water treatment unit 3, a sewage softening unit 31, a nanofiltration concentrated water softening unit 32, a third adjusting tank 301, a primary softening unit 302, a secondary softening unit 303, a third sludge concentration tank 304, a third filter press 305, a coagulation tank A3011, a coagulation tank B3012, a third flocculation tank 3013, a third sedimentation tank 3014, a depth treatment unit 4, a fourth adjusting tank 41, a mechanical clarification tank 42, a fourth sludge concentration tank 43, a fourth filter press 44, an intermediate 45, a multi-medium filter 46, a self-cleaning filter 47, a, An ultrafiltration device 48, an ultrafiltration water tank 49, a nanofiltration cartridge filter 410, a nanofiltration device 411, a nanofiltration water tank 412, a high-salt water tank 413, an RO cartridge filter 414, an RO device 415, an RO concentrate water tank 416, a concentrate RO cartridge filter 417, a concentrate RO device 418, a high-concentration water tank 419, a concentration treatment unit 5, a fifth adjusting tank 51, a multi-media filtration device 52, a filtration water producing tank 53, a primary ion exchange device 54, a decarbonizer 55, a first intermediate water tank 56, a primary reverse osmosis device 57, a reverse osmosis water producing tank 58, a second intermediate water tank 59, a concentrate ion exchange device 510, a third intermediate water tank 511, a concentrate reverse osmosis device 512, a wastewater collecting tank 513, a concentration crystallization unit 6, a sixth adjusting tank 61, a primary precipitation device 62, an ammonia stripping device 63, a secondary precipitation device 64, a precipitation water producing tank 65, a first sand filtration device 66, an ultrafiltration water producing tank 68, a ultrafiltration water tank 68, a second intermediate water tank 61, a third adjusting tank 61, a second adjusting tank 60, a third adjusting tank 6, a third adjusting tank, a fourth adjusting tank 6, a fourth adjusting tank 6, a fourth adjusting tank 6, a fourth adjusting tank 6, a fourth adjusting tank, a fourth adjusting, A chelating resin bed 69, a resin water producing tank 610, an organic concentration device 611, a nanofiltration device 612, a sodium sulfate buffer tank 613, a sodium sulfate freezing and crystallizing device 614, a sodium sulfate hot melting and evaporating device 615, a sodium sulfate centrifugal drying device 616, a nanofiltration water producing tank 617, a primary RO device 618, an RO concentrated water tank 619, an ozone oxidation device 620, a sodium chloride evaporating tank 621, a sodium chloride multi-effect evaporation crystallizer 622, a sodium chloride centrifugal drying device 623, a mixed salt evaporation and crystallization device 624, a miscellaneous salt drying device 625, a secondary RO water inlet adjusting tank 626, a secondary RO device 627, a deamination resin bed 628, a gasified grey water source 7, a domestic sewage source 8, a desalted water and waste water source 9, a circulating waste water and waste water source 10, other waste water sources 11 and a reuse water tank 12.

The specific implementation mode is as follows:

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, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1:

1-6, the high-salinity wastewater treatment system comprises a gasified grey water source 7, a domestic sewage source 8, a desalted water and sewage source 9, a circulating water and sewage source 10, other sewage sources 11, a gasification high-density unit 1, a biochemical treatment unit 2, a softened water treatment unit 3, a deep treatment unit 4, a concentration treatment unit 5, a concentration and crystallization unit 6 and a reuse water tank 12;

the water outlet of the gasified ash water source 7 and the water outlet of the domestic sewage source 8 are communicated with the water inlet of the first regulating tank 101 of the gasified high-density unit 1 through pipelines, the supernatant outlet of the first sedimentation tank 105 of the gasified high-density unit 1 is communicated with the water inlet of the second regulating tank 201 of the biochemical treatment unit 2 through pipelines, the water outlet of the biological aerated filter 204 of the biochemical treatment unit 2 is communicated with the water inlet of the third regulating tank 301 of the sewage softening unit 31 of the softened water treatment unit 3 through pipelines, the water outlet of the third sedimentation tank 3014 of the secondary softening unit 303 of the sewage softening unit 31, the water outlet of the third sedimentation tank 3014 of the secondary softening unit 303 of the nano-filtered concentrated water softening unit 32 of the softened water treatment unit 3, the water outlet of the desalted water sewage source 9, the water outlet of the circulating sewage source 10 and the water outlets of other sewage sources 11 are communicated with the water inlet of the fourth regulating tank 41 of the deep treatment unit 4 through pipelines, the water outlet of the high-salt water tank 413 of the advanced treatment unit 4 is communicated with the water inlet of the third regulating tank 301 of the nanofiltration concentrated water softening unit 32 of the softened water treatment unit 3 through a pipeline, the water outlet of the RO device 415 of the advanced treatment unit 4 and the water outlet of the concentrated water RO device 418 are both communicated with the water inlet of the reuse water tank 12 through pipelines, the water outlet of the high-concentration water tank 419 of the advanced treatment unit 4 is communicated with the water inlet of the fifth regulating tank 51 of the concentration treatment unit 5 through a pipeline, the concentrated water outlet of the concentrated water reverse osmosis device 512 of the concentration treatment unit 5 is communicated with the water inlet of the sixth regulating tank 61 of the concentration crystallization unit 6 through a pipeline, and the water outlet of the deamination resin bed 628 of the concentration crystallization unit 6 is communicated with the water inlet of the reuse water tank 12.

Further, the gasification high-density unit 1 comprises a first adjusting tank 101, a first reaction tank 102, a first coagulation tank 103, a first flocculation tank 104, a first sedimentation tank 105, a first sludge concentration tank 106 and a first filter press 107;

the water outlet of the first adjusting tank 101 is communicated with the water inlet of the first reaction tank 102 through a pipeline, the water outlet of the first reaction tank 102 is communicated with the inlet of the first coagulation tank 103 through a pipeline, the outlet of the first coagulation tank 103 is communicated with the water inlet of the first flocculation tank 104 through a pipeline, the water outlet of the first flocculation tank 104 is communicated with the water inlet of the first sedimentation tank 105 through a pipeline, the sludge outlet of the first sedimentation tank 105 is divided into two paths, one path is communicated with the inlet of the first coagulation tank 103 through a pipeline, the other path is communicated with the inlet of the first sludge concentration tank 106 through a pipeline, the sludge outlet of the first sludge concentration tank 106 is communicated with the inlet of the first filter press 107 through a pipeline, and the supernatant outlet of the first sludge concentration tank 106 and the supernatant outlet of the first filter press 107 are communicated with the water inlet of the first adjusting tank through pipelines.

Further, the biochemical treatment unit 2 comprises a second adjusting tank 201, an air flotation tank 202, a biochemical tank 203, a biological aerated filter 204, a second sludge concentration tank 205 and a second filter press 206;

the water outlet of the second adjusting tank 201 is communicated with the water inlet of the air flotation tank 202 through a pipeline, the water outlet of the air flotation tank 202 is communicated with the water inlet of the biochemical tank 203 through a pipeline, the water outlet of the biochemical tank 203 is communicated with the water inlet of the biological aerated filter 204 through a pipeline, the sludge outlet of the biochemical tank 203 is communicated with the inlet of the second sludge concentration tank 205 through a pipeline, the sludge outlet of the second sludge concentration tank 205 is communicated with the inlet of the second filter press 206 through a pipeline, and the supernatant outlets of the second sludge concentration tank 205 and the second filter press 206 are communicated with the inlet of the second adjusting tank 201 through pipelines.

Further, the softened water treatment unit 3 comprises a sewage softening unit 31 and a nanofiltration concentrated water softening unit 32;

the sewage softening unit 31 and the nanofiltration concentrated water softening unit 32 have the same structure and respectively comprise a third regulating tank 301, a primary softening unit 302, a secondary softening unit 303, a third sludge concentration tank 304 and a third filter press 305;

the primary softening unit 302 and the secondary softening unit 303 respectively comprise a coagulation tank A3011, a coagulation tank B3012, a third flocculation tank 3013 and a third sedimentation tank 3014 which are sequentially connected in series;

a water outlet of the third regulating tank 301 is communicated with a water inlet of the coagulation tank A3011 of the primary softening unit 302 through a pipeline, and a supernatant outlet of the third sedimentation tank 3014 of the primary softening unit 302 is communicated with a water inlet of the coagulation tank A3011 of the secondary softening unit 303 through a pipeline; the sludge outlet of the third sedimentation tank 3014 of the primary softening unit 302 is divided into three paths, wherein two paths are respectively communicated with the coagulation tank A3011 and the coagulation tank B3012 of the primary softening unit 302 through pipelines, and the third path is communicated with the inlet of the third sludge concentration tank 304 through a pipeline; the sludge outlet of the third sedimentation tank 3014 of the second-stage softening unit 303 is divided into three paths, wherein two paths are respectively communicated with the coagulation tank A3011 and the coagulation tank B3012 of the second-stage softening unit 303 through pipelines, and the third path is communicated with the inlet of the third sludge concentration tank 304 through a pipeline;

the sludge outlet of the third sludge concentration tank 304 is communicated with the inlet of the third filter press 305 through a pipeline, and the supernatant outlet of the third sludge concentration tank 304 and the supernatant outlet of the third filter press 305 are both communicated with the water inlet of the third regulating tank 301 through pipelines.

Further, the advanced treatment unit 4 includes a fourth regulation tank 41, a mechanical clarifier 42, a fourth sludge concentration tank 43, a fourth filter press 44, an intermediate water tank 45, a multimedia filter 46, a self-cleaning filter 47, an ultrafiltration device 48, an ultrafiltration water tank 49, a nanofiltration cartridge filter 410, a nanofiltration device 411, a nanofiltration water tank 412, a high-salt water tank 413, an RO cartridge filter 414, an RO device 415, an RO high-concentration water tank 416, a concentrated RO cartridge filter 417, a concentrated RO device 418, and a high-concentration water tank 419;

the water outlet of the fourth regulating reservoir 41 is communicated with the water inlet of the mechanical clarifier 42 through a pipeline, the sludge outlet of the mechanical clarifier 42 is communicated with the inlet of the fourth sludge concentration tank 43 through a pipeline, the sludge outlet of the sludge concentration tank is communicated with the inlet of the fourth filter press 44 through a pipeline, and the supernatant outlets of the fourth sludge concentration tank 43 and the fourth filter press 44 are communicated with the water inlet of the fourth regulating reservoir 41 through pipelines; the supernatant outlet of the mechanical clarification tank 42 is communicated with the water inlet of the intermediate water tank 45 through a pipeline, the water outlet of the intermediate water tank 45 is communicated with the water inlet of the multi-medium filter 46 through a pipeline, the water outlet of the multi-medium filter 46 is communicated with the water inlet of the self-cleaning filter 47 through a pipeline, the water outlet of the self-cleaning filter 47 is communicated with the water inlet of the ultrafiltration device 48 through a pipeline, the water outlet of the ultrafiltration device 48 is communicated with the water inlet of the ultrafiltration water tank 49 through a pipeline, the water outlet of the ultrafiltration water tank 49 is communicated with the water inlet of the nanofiltration cartridge filter 410 through a pipeline, the water outlet of the nanofiltration cartridge filter 410 is communicated with the water inlet of the nanofiltration device 411 through a pipeline, the concentrated water outlet of the nanofiltration device 411 is communicated with the water inlet of the high-salinity water 413 through a pipeline, the water outlet of the nanofiltration device 411 is communicated with the water inlet of the nanofiltration water tank 412 through a pipeline, and the water outlet of the RO water tank 412 is communicated with the water inlet of the cartridge filter 414 through a pipeline, the water outlet of the RO cartridge filter 414 is communicated with the water inlet of the RO device 415 through a pipeline, the concentrated water outlet of the RO device 415 is communicated with the water inlet of the RO concentrated water tank 416 through a pipeline, the water outlet of the RO concentrated water tank 416 is communicated with the water inlet of the concentrated water RO cartridge filter 417 through a pipeline, the water outlet of the concentrated water RO cartridge filter 417 is communicated with the water inlet of the concentrated water RO device 418 through a pipeline, and the concentrated water outlet of the concentrated water RO device 418 is communicated with the water inlet of the high-concentration water tank 419 through a pipeline.

Further, the concentration processing unit 5 includes a fifth adjusting tank 51, a multi-media filtering device 52, a filtering product water tank 53, a primary ion exchange device 54, a decarbonizer 55, a first intermediate water tank 56, a primary reverse osmosis device 57, a reverse osmosis product water tank 58, a second intermediate water tank 59, a concentrated water ion exchange device 510, a third intermediate water tank 511, and a concentrated water reverse osmosis device 512;

the water outlet of the fifth adjusting tank 51 is communicated with the water inlet of the multi-medium filtering device 52 through a pipeline, the water outlet of the multi-medium filtering device 52 is communicated with the water inlet of the filtering product water tank 53 through a pipeline, the water outlet of the filtering product water tank 53 is communicated with the water inlet of the first-stage ion exchange device 54 through a pipeline, the water outlet of the first-stage ion exchange device 54 is communicated with the water inlet of the decarbonizer 55 through a pipeline, the water outlet of the decarbonizer 55 is communicated with the water inlet of the first intermediate water tank 56 through a pipeline, the water outlet of the first intermediate water tank 56 is communicated with the water inlet of the first-stage reverse osmosis device 57 through a pipeline, the water outlet of the first-stage reverse osmosis device 57 is communicated with the water inlet of the reverse osmosis product water tank 58 through a pipeline, the concentrated water outlet of the first-stage reverse osmosis device 57 is communicated with the water inlet of the second intermediate water tank 59 through a pipeline, and the water outlet of the second intermediate water tank 59 is communicated with the water inlet of the concentrated water ion exchange device 510 through a pipeline, the water outlet of the concentrated water ion exchange device 510 is communicated with the water inlet of the third intermediate water tank 511 through a pipeline, and the water outlet of the third intermediate water tank 511 is communicated with the water inlet of the concentrated water reverse osmosis device 512 through a pipeline.

The water outlet of the filtering water generating tank 53 is divided into two paths, one path is communicated with a washing water inlet of the multi-medium filtering device 52 through a pipeline, and the other path is communicated with a washing water inlet of the primary ion exchange device 54 through a pipeline; the water outlet of the reverse osmosis water production tank 58 is communicated with the flushing water inlet of the first-stage reverse osmosis device 57 through a pipeline; the water outlet of the second intermediate water tank 59 is also communicated with the flushing water inlet of the concentrated water ion exchange device 510 through a pipeline;

the flushing water outlet of the multi-media filtering device 52, the flushing water outlet of the primary ion exchange device 54, the flushing water outlet of the primary reverse osmosis device 57 and the flushing water outlet of the concentrated water ion exchange device 510 are communicated with the water inlet of the wastewater collection tank 513 through pipelines, and the water outlet of the wastewater collection tank 513 is communicated with the water inlet of the fifth adjusting tank 51 through a pipeline.

The concentration and crystallization unit 6 comprises a sixth regulating tank 61, a primary precipitation device 62, an ammonia stripping device 63, a secondary precipitation device 64, a precipitation product water tank 65, a first sand filtration device 66, an ultrafilter 67, an ultrafiltration product water tank 68, a chelating resin bed 69, a resin product water tank 610, an organic concentration device 611, a nanofiltration device 612, a sodium sulfate buffer tank 613, a sodium sulfate freezing and crystallization device 614, a sodium sulfate hot melting and evaporation device 615, a sodium sulfate centrifugal drying device 616, a nanofiltration product water tank 617, a primary RO device 618, an RO concentrated water tank 619, an ozone oxidation device 620, a sodium chloride evaporation water tank 621, a sodium chloride multi-effect evaporation crystallizer 622, a sodium chloride centrifugal drying device 623, a mixed salt evaporation and crystallization device 624, a mixed salt drying device 625, a secondary RO water inlet regulating tank 626, a secondary RO device 627 and a deamination resin bed 628;

the water outlet of the sixth regulating tank 61 is communicated with the water inlet of the first-stage sedimentation device 62 through a pipeline, the supernatant outlet of the first-stage sedimentation device 62 is communicated with the water inlet of the ammonia stripping device 63 through a pipeline, the water outlet of the ammonia stripping device 63 is communicated with the water inlet of the second-stage sedimentation device 64 through a pipeline, the supernatant outlet of the second-stage sedimentation device 64 is communicated with the water inlet of the sedimentation product water tank 65 through a pipeline, the water outlet of the sedimentation product water tank 65 is communicated with the water inlet of the first sand filtration device 66 through a pipeline, the water outlet of the first sand filtration device 66 is communicated with the water inlet of the ultra-filtration device 67 through a pipeline, the water outlet of the ultra-filtration device 67 is communicated with the water inlet of the ultra-filtration product water tank 68 through a pipeline, the water outlet of the ultra-filtration product water tank 68 is communicated with the water inlet of the chelate resin bed 69 through a pipeline, and the water outlet of the chelate resin bed 69 is communicated with the water inlet of the resin product water tank 610 through a pipeline, the water outlet of the resin water producing tank 610 is communicated with the water inlet of the organic concentration device 611 through a pipeline, the water producing outlet of the organic concentration device 611 is communicated with the water inlet of the nanofiltration device 612 through a pipeline, the concentrated water outlet of the nanofiltration device 612 is communicated with the water inlet of the sodium sulfate buffer tank 613 through a pipeline, the water outlet of the sodium sulfate buffer tank 613 is communicated with the water inlet of the sodium sulfate freezing and crystallizing device 614 through a pipeline, the crystal slurry outlet of the sodium sulfate freezing and crystallizing device 614 is communicated with the inlet of the sodium sulfate hot melting and evaporating device 615 through a pipeline, and the outlet of the sodium sulfate hot melting and evaporating device 615 is communicated with the inlet of the sodium sulfate centrifugal drying device 616 through a pipeline;

the water outlet of the nano filter 612 is communicated with the water inlet of the nano-filtration water production tank 617 through a pipeline, the water outlet of the nano-filtration water production tank 617 is communicated with the water inlet of the primary RO device 618 through a pipeline, the water outlet of the primary RO device 618 is communicated with the water inlet of the secondary RO water inlet regulating reservoir 626 through a pipeline, the water outlet of the secondary RO water inlet regulating reservoir 626 is communicated with the water inlet of the secondary RO device 627 through a pipeline, and the water outlet of the secondary RO device 627 is communicated with the water inlet of the deamination resin bed 628 through a pipeline; the concentrated water outlet of the first-stage RO device 618 is communicated with the water inlet of an RO concentrated water tank 619 through a pipeline, the water outlet of the RO concentrated water tank 619 is communicated with the water inlet of an ozone oxidation device 620 through a pipeline, the water outlet of the ozone oxidation device 620 is communicated with the water inlet of a sodium chloride evaporation water tank 621 through a pipeline, the water outlet of the sodium chloride evaporation water tank 621 is communicated with the water inlet of a sodium chloride multiple-effect evaporation crystallizer 622 through a pipeline, the crystal slurry outlet of the sodium chloride multiple-effect evaporation crystallizer 622 is communicated with the inlet of a sodium chloride centrifugal drying device 623 through a pipeline, the mother liquor outlet of the sodium chloride multiple-effect evaporation crystallizer 622, the concentrated water outlet of the organic concentration device 611 is communicated with the inlet of the mixed salt evaporative crystallization device 624 through a pipeline, and the outlet of the mixed salt evaporative crystallization device 624 and the mother liquor outlet of the sodium sulfate freezing crystallization device 614 are communicated with the inlet of the mixed salt drying device 625 through pipelines.

The working principle is as follows:

the gasification grey water and domestic sewage generated by the coal-based methanol firstly enter a first regulating tank 101 of a gasification high-density unit 1, enter a first reaction tank 102 after homogenization and flow equalization, and are prepared into Mg (OH) by adding MgO₂Adding Ca (OH) into the solution₂And NaOH, Na₂CO₃Control of pH > 10.5 in water, silicate and Mg (OH)₂The reaction generates insoluble colloidal precipitate Mg (HSiO)₃)₂Precipitation, simultaneous production of CaCO in the pond₃Precipitating; then the mixture enters a first coagulation tank 103, and the sedimentation of insoluble substances can be accelerated by adding PFS; then the sludge enters a first flocculation tank 104, insoluble substances are polymerized and the volume is increased by adding PAM, and then the sludge enters a first sedimentation tank 105 for sedimentation, a part of the settled sludge flows back to a first coagulation tank 103 to continuously participate in coagulation sedimentation for reaction, a part of the settled sludge directly enters a sludge concentration tank, the water content in the sludge is reduced by filter pressing and then the sludge is transported outwards, and further the effects of removing silicon and hardness are achieved; the supernatant produced after precipitation then enters the subsequent biochemical treatment unit 2. The water inlet index of the gasification high-density unit 1 is shown in table 1.

TABLE 1 gasification high Density Unit 1 Water intake index

Analysis item	Unit of	Index (I)
			pH	—	8.1
TDS	mg/L	6505
			COD	mg/L (calculated as CaCO 3)	1018
Sodium salt	mg/L	0
			Potassium salt	mg/L	0
Calcium carbonate	mg/L	1357
			Magnesium alloy	mg/L	43
NH4-N	mg/L	372
			Chlorine	mg/L	336
Sulfate radical	mg/L	3155
			Bicarbonate radical	mg/L	1031
Nitrate radical	mg/L	0
			Fluorine	mg/L	0
Total silicon	mg/L	211

After the second adjusting tank 201 is homogenized and equalized, the obtained mixture enters an air floatation tank 202, flocs contained in the mixture are combined with micro bubbles, and the mixture floats upwards under the action of buoyancy, so that the purposes of removing part of CODcr, BOD5, SS (suspended solids in water) and the like are achieved. Then, the sewage enters a biochemical tank 203 for degrading organic matters and nutritional pollutants, and then passes through a biological aeration filter 204, so that not only can the COD content be reduced through biological oxidation, but also suspended matters can be intercepted. The water inlet indexes of the biochemical treatment unit 2 are shown in Table 2.

TABLE 2 Biochemical treatment Unit 2 Water inflow index

Analysis item	Unit of	Index (I)
			pH	—	8.1
TDS	mg/L	4876
			COD	mg/L (calculated as CaCO 3)	916
Sodium salt	mg/L	230
			Potassium salt	mg/L	0
Calcium carbonate	mg/L	40
			Magnesium alloy	mg/L	1
NH4-N	mg/L	372
			Chlorine	mg/L	336
Sulfate radical	mg/L	3547
			Bicarbonate radical	mg/L	300
Nitrate radical	mg/L	0
			Fluorine	mg/L	0
Total silicon	mg/L	50

After biochemical treatment, the sewage enters a softened water treatment unit 3 to further solve the problems of high sewage hardness and high silicon content, so that the water recycling device in subsequent advanced treatment can stably operate; specifically, the sewage after biochemical treatment firstly enters a third regulating tank 301 of a sewage softening unit 31 and then enters a first-level softening unit 302, and MgO is added into a coagulation tank A3011 to prepare Mg (OH)₂Adding Ca (OH) into the solution in a coagulation tank B₂And NaOH, Na₂CO₃PFS, control of pH > 10.5 in water, silicate and Mg (OH)₂The reaction generates insoluble colloidal precipitate Mg (HSiO)₃)₂Precipitation, simultaneous production of CaCO in the pond₃And (3) precipitating, namely adding PAM into the third flocculation tank 3013 to polymerize and increase the volume of the PAM, so that the PAM enters the third sedimentation tank 3014 to precipitate, returning part of the precipitated sludge to the coagulation tank A3011 and the coagulation tank B3012 to continuously participate in coagulation and sedimentation for reaction, and directly discharging part of the precipitated sludge into the third sludge concentration tank 304 to achieve the effects of removing silicon and hardness.

Then the sewage enters a secondary softening unit 303, enters a coagulation tank A3011 of the secondary softening unit 303, and is added with MgO to prepare Mg (OH)₂Adding NaOH and PFS into the coagulation tank B3012, controlling the pH value in the water to be more than 10.5, and adding silicate and Mg (OH)₂The reaction generates insoluble colloidal precipitate Mg (HSiO)₃)₂Precipitation, simultaneous production of CaCO in the pond₃Precipitating by adding PAM into the third flocculation tank 3013 to polymerize and increase its volume, and allowing to enter the third sedimentation tank 3014And (3) performing sedimentation, wherein a part of the precipitated sludge flows back to the coagulation tank A3011 and the coagulation tank B3012 to continue to participate in coagulation sedimentation for reaction, and a part of the precipitated sludge is directly discharged into the third sludge concentration tank 304, so that the effects of removing silicon and hardness are achieved. The water inlet index of the sewage softening unit 31 is shown in table 3.

TABLE 3 Water inflow index of the Sewage softening Unit 31

Softened soft water, desalted water sewage, circulating water sewage and other sewage enter a fourth regulating tank 41 for homogenization and flow equalization, PAC or PAM reagent is added to perform mixing reaction in a pipeline, and then the mixture enters a mechanical clarification tank 42 for reaction, precipitation and purification treatment so as to remove calcium and magnesium ion crystallization precipitates and organic impurities precipitated by reaction coagulation, reduce turbidity, preliminarily clarify the water body, and enable the turbidity of the effluent to be less than about 10 mg/L. The sludge in the sedimentation tank is scraped by a mud scraper and then is sent into a fourth sludge concentration tank 43 by a sludge conveying pump, and then is pumped into a box-type fourth filter press 44 by a sludge concentration pump to be dewatered, and then the sludge is transported outside.

The effluent indexes of the mixed effluent of the sewage softening unit 31 and the nanofiltration concentrated water softening unit 32 are shown in a table 4, the incoming water index of the desalted water effluent is shown in a table 5, and the reuse water index of the advanced treatment unit 4 is shown in a table 6.

TABLE 4 softened water effluent index

Analysis item	Unit of	Index (I)
			pH	—	7～11
Total alkalinity	mg/L(CaCO₃Meter)	≤600
			Total hardness	mg/L(CaCO₃Meter)	≤200
Ca2+	mg/L(CaCO₃Meter)	≤200
			Soluble silicon	mg/L	<15
CODcr	mg/L	≤150
			Suspended Substance (SS)	mg/L	≤20

TABLE 5 incoming water index of desalted water and sewage

TABLE 6 index of reuse water for the advanced treatment unit 4

The mechanical clarification tank 42 is a precipitation device integrating coagulation reaction, precipitation, sludge scraping and sludge discharging, and is subjected to secondary coagulation reaction in a reaction zone of the separation device, so that PAC is in full contact reaction with raw water, and is subjected to solid-liquid separation in a primary precipitation zone to precipitate large suspended matters, and water subjected to the primary solid-liquid separation forms a uniform flow state and flows to the intermediate water tank 45 from a water distribution tank at the top of the filter tank. Water in the intermediate water tank 45 is pumped into the multi-media filter 46 through the filtering pressure pump for primary filtration and then enters the self-cleaning filter 47, and soft water meeting the ultrafiltration condition is obtained. The water enters an ultrafiltration device 48 for filtration, and the filtered water enters an ultrafiltration water pool 49.

After the scale inhibitor and the reducing agent are added into the produced water from ultrafiltration by the chemical adding device, the produced water is firstly pumped into a nanofiltration cartridge filter 410 by a nanofiltration booster pump for primary filtration to prevent a nanofiltration membrane from being blocked, and then enters a nanofiltration device 411 by a nanofiltration high-pressure pump, and the produced water from nanofiltration is pumped into a back-stage process by a reverse osmosis booster pump. And the strong brine generated by nanofiltration enters a nanofiltration concentrated water softening unit 32 of the softened water treatment unit 3 for softening treatment after being collected in a high-brine water tank 413. The water inlet index of the nanofiltration concentrated water softening unit 32 is shown in table 7.

TABLE 7 Water inflow index of nanofiltration concentrated water softening unit 32

Nanofiltration product water from a nanofiltration water tank 412 is pumped into an RO cartridge filter 414 through a reverse osmosis booster pump, and then is pumped into an RO device 415 through a primary high-pressure pump, so as to realize primary separation, the product water is sent to a reuse water tank 12 for water circulation in a plant area, concentrated water is sent to a concentrated water RO cartridge filter 417 through a reverse osmosis primary booster pump, a secondary booster pump and a concentrated water reverse osmosis booster pump, and then is sent to a concentrated water RO device 418 through a concentrated water reverse osmosis high-pressure pump for separation, the separated product water is sent to the reuse water tank 12 for recycling, the concentrated water is sent to a high-concentration water tank 419 for collection, and is sent to a concentration treatment unit 5 through a high-salt water discharge pump. The water inlet index of the concentration unit is shown in Table 8.

TABLE 8 Water intake index of the concentration Unit

The strong brine in the high-concentration water tank 419 is conveyed to the fifth regulating tank 51 through a pipeline and then pumped into the multi-medium filtering device 52 through the lift pump, and the main purpose of the device is to further treat the turbidity in the water and meet the requirement of ion exchange water inlet. In this embodiment, the multi-media filter device 52 is a structure of a combination of anthracite filter material and quartz sand filter material. The filtered clear liquid is treated by a primary ion exchange device 54, then is conveyed to a decarbonizer 55 by a pump, and the pH of the clear liquid is reduced by adjusting the decarbonizer 55, so that the concentration of carbonate in water is reduced, and the generated precipitate is prevented from accumulating on the surface of a subsequent reverse osmosis membrane; increased removal of carbon dioxide by the packing in the air-blowing and decarbonizing 55, and CO formed₂The gas is discharged into the atmosphere through the top, the effluent flows into a first intermediate water tank 56, the pH is adjusted to be alkaline by adding NaOH, the effluent enters a first-stage reverse osmosis device 57, and the generated concentrated water is subjected to ion exchange and then to reverse osmosis againAnd (4) permeating to achieve the effect of concentration, and enabling the obtained concentrated water to enter a subsequent concentration and crystallization unit 6. The effluent index of the concentration unit is shown in Table 9.

TABLE 9 effluent index of concentration unit

Analysis item	Unit of	Index (I)
			pH	-	7.0-9.0
CD	ms/cm	80-100
			TDS	g/L	Not less than 50
Amount of discharged concentrated water	m³/h	Not higher than 10
			Ammonia nitrogen	mg/L	Not more than 15
CODcr	mg/L	Not more than 100

Concentrated incoming water firstly enters a sixth regulating tank 61 to be uniformly mixed and then enters a first-stage precipitation device 62 through a lift pump, the contents of calcium, magnesium and silicon in the wastewater are reduced by adding medicaments such as calcium hydroxide, sodium carbonate, magnesium oxide, PFS, PAM and the like, so that the wastewater is precipitated and separated, the supernatant generated after precipitation is subjected to air stripping treatment, strong ammonia contained in the supernatant is removed, then the supernatant enters a second-stage precipitation device 64, sludge is removed through precipitation again, and the supernatant enters a first sand filtration device 66 to remove the residual SS in the wastewater; the sand-filtered effluent enters an ultrafilter 67 to further remove residual SS and colloid in the wastewater, and the turbidity of the effluent of the ultrafiltration system is less than 3NTU, so that the long-term stable operation of a subsequent membrane system can be ensured. The ultrafiltration water product enters an ultrafiltration water production tank 68, is subjected to hardness removal again through chelating resin, enters an organic concentration device 611, is subjected to high-power concentration through aggregation of macromolecular organic matters in the brine into larger individuals through a physical and chemical method, is subjected to nanofiltration salt separation through the organic concentration device 611 to obtain nanofiltration concentrated water with the main component of sodium sulfate, and is crystallized, evaporated and dried to obtain sodium sulfate. And (4) performing reverse osmosis on the nanofiltration produced water, and performing reverse osmosis treatment and deamination treatment on the obtained produced water to obtain reuse water. And (3) carrying out oxidation treatment on concentrated water obtained by carrying out reverse osmosis on nanofiltration water to reduce COD (chemical oxygen demand), so as to obtain sodium chloride evaporated water with a main component of sodium chloride, and evaporating and drying the sodium chloride evaporated water to obtain sodium chloride. And mixing, evaporating, crystallizing and drying mother liquor generated in the processes of sodium chloride crystallization and sodium sulfate crystallization to obtain the mixed salt.

Through this project, can produce sodium chloride: 3032 ton/year, sodium sulfate: 224 tons/year, miscellaneous salts: 1040 ton/year.

The device is reasonable in configuration, can effectively reduce the discharge of sewage, and improves the utilization rate of resources. The method conforms to the national 'clean production promotion law', energy conservation, consumption reduction, environmental protection and other industrial policies and basic national policy. The production technology reaches the domestic advanced level. Can more effectively utilize sewage cycle utilization rate, effectively promote the discarded object utilization efficiency of enterprise, reduce the environmental protection risk, promote the guarantee of company's profit.

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

1. A high-salinity wastewater treatment system is characterized by comprising a gasified grey water source, a domestic sewage source, a desalted water and sewage source, a circulating water and sewage source, other sewage sources, a gasification high-density unit, a biochemical treatment unit, a softened water treatment unit, a deep treatment unit, a concentration crystallization unit and a reuse water tank;

2. The high-salinity wastewater treatment system according to claim 1, wherein the gasification high-density unit comprises a first regulating tank, a first reaction tank, a first coagulation tank, a first flocculation tank, a first sedimentation tank, a first sludge concentration tank and a first filter press;

3. The high-salinity wastewater treatment system according to claim 1, wherein the biochemical treatment unit comprises a second adjusting tank, an air flotation tank, a biochemical tank, a biological aerated filter, a second sludge concentration tank and a second filter press;

4. The high salinity wastewater treatment system according to claim 1, wherein the softened water treatment unit comprises a sewage softening unit and a nanofiltration concentrated water softening unit;

5. The high-salinity wastewater treatment system according to claim 1, wherein the advanced treatment unit comprises a fourth conditioning tank, a mechanical clarifier, a fourth sludge thickener, a fourth filter press, an intermediate water tank, a multi-media filter, a self-cleaning filter, an ultrafiltration device, an ultrafiltration water tank, a nanofiltration cartridge filter, a nanofiltration device, a nanofiltration water tank, a high-salinity water tank, an RO cartridge filter, an RO device, an RO concentrate tank, a concentrate RO cartridge filter, a concentrate RO device, and a high-concentration water tank;

6. The high-salinity wastewater treatment system according to claim 1, wherein the concentration treatment unit comprises a fifth regulating reservoir, a multi-media filtering device, a filtering water producing reservoir, a primary ion exchange device, a decarbonizer, a first intermediate water tank, a primary reverse osmosis device, a reverse osmosis water producing tank, a second intermediate water tank, a concentrated water ion exchange device, a third intermediate water tank and a concentrated water reverse osmosis device;

7. The high-salinity wastewater treatment system according to claim 1, wherein the concentration and crystallization unit comprises a sixth adjusting tank, a primary precipitation device, an ammonia stripping device, a secondary precipitation device, a precipitation water production tank, a first sand filtration device, an ultrafilter, an ultrafiltration water production tank, a chelating resin bed, a resin water production tank, an organic concentration device, a nanofilter, a sodium sulfate buffer tank, a sodium sulfate freezing and crystallizing device, a sodium sulfate hot-melting and evaporating device, a sodium sulfate centrifugal drying device, a nanofiltration water production tank, a primary RO device, an RO concentrated water tank, an ozone oxidation device, a sodium chloride evaporating tank, a sodium chloride multi-effect evaporation crystallizer, a sodium chloride centrifugal drying device, a mixed salt evaporation and crystallization device, a mixed salt drying device, a secondary RO water inlet adjusting tank, a secondary RO device and a deamination resin bed;

8. The high-salinity wastewater treatment system according to claim 6, wherein the water outlet of the filtration and water production tank is divided into two paths, one path is communicated with the flushing water inlet of the multi-media filtration device through a pipeline, and the other path is communicated with the flushing water inlet of the primary ion exchange device through a pipeline; the water outlet of the reverse osmosis water production tank is communicated with the flushing water inlet of the first-stage reverse osmosis device through a pipeline; the water outlet of the second intermediate water tank is also communicated with a flushing water inlet of the concentrated water ion exchange device through a pipeline;