CN113526767A - Color coating wastewater treatment system and treatment method - Google Patents

Abstract

The invention provides a color coating wastewater treatment system and a treatment method, wherein the treatment system comprises: the aeration device is used for carrying out micropore aeration on the color coating wastewater; the oil removing device is added with a first medicament for flocculation and precipitation, and grease is removed by an air floatation method; the sedimentation device is added with a second medicament for flocculation and sedimentation to form alum blossom; a filtering device for filtering to obtain clear liquid; the reverse osmosis water treatment device is used for sequentially carrying out reverse osmosis pretreatment, primary reverse osmosis water treatment, secondary reverse osmosis water treatment, tertiary reverse osmosis water treatment and disc tube type reverse osmosis water treatment on the clear liquid to obtain concentrated water; and the evaporative crystallization device is used for carrying out evaporative concentration on the concentrated water to obtain salt slag and pure water. Through carrying out micropore aeration, flocculation and precipitation and filtration on the color coating wastewater, grease, COD (chemical oxygen demand) and ammonia nitrogen in the color coating wastewater are effectively removed, and then salt slag and pure water are obtained through multi-stage reverse osmosis water treatment combined with evaporation and concentration, so that zero emission treatment of the color coating wastewater and recycling of resources are realized.

Description

Color coating wastewater treatment system and treatment method

Technical Field

The invention relates to the technical field of wastewater treatment, in particular to a color coating wastewater treatment system and a color coating wastewater treatment method.

Background

The color coating waste water comes from the working sections of pretreatment, cleaning, water quenching and the like in the production of color coating steel plates, and various water quality indexes of the color coating waste water have difference due to different technical processes, and the general water quality is characterized in that COD is more than 1000mg/L, oil content is about 100mg/L, and the water is slightly alkaline (pH value is more than 10).

Under the condition that water resource shortage and water pollution are serious in China and water environment faces an extremely severe situation, a series of policy measures are continuously taken in recent years by China, the fields of industrial pollution, urban pollution, agricultural and rural pollution, ship and port pollution and the like are aimed, especially, clear requirements are provided for industrial sewage treatment, emission standards are improved, and the trend of policy guidance and industrial development is common to encourage sewage treatment and recycling and zero emission. The existing industrial sewage farm mostly adopts the traditional biochemical treatment technology, the process is simple, the technical level is relatively laggard, and the treatment effect and the stability are difficult to reach the new discharge standard.

Disclosure of Invention

The invention aims to provide a color-coating wastewater treatment system and a color-coating wastewater treatment method, which have good treatment effect, do not cause secondary pollution, and realize zero-emission treatment of color-coating wastewater and recycling of resources.

In order to achieve the above object, according to a first aspect of the present invention, there is provided a color-coating wastewater treatment system comprising an aeration device, an oil removal device, a precipitation device, a filtration device, a reverse osmosis water treatment device, and an evaporative crystallization device, which are connected in series, wherein:

the aeration device is used for carrying out micropore aeration on the color coating wastewater;

the oil removing device is used for adding a first medicament into the color coating wastewater for flocculation and precipitation to generate oleophilic floccules, and removing grease by an air floatation method to obtain a first treatment liquid;

the precipitation device is used for adding a second medicament into the first treatment liquid for flocculation precipitation to form alum floc so as to obtain a second treatment liquid;

the filtering device is used for filtering the second treatment liquid to obtain clear liquid;

the reverse osmosis water treatment device is used for sequentially carrying out reverse osmosis pretreatment, primary reverse osmosis water treatment, secondary reverse osmosis water treatment, tertiary reverse osmosis water treatment and disc tube type reverse osmosis water treatment on the clear liquid to obtain concentrated water;

and the evaporative crystallization device is used for carrying out evaporative concentration on the concentrated water to obtain salt slag and pure water.

Optionally, the aeration device includes an aeration reaction tank and a first aerator arranged in the aeration reaction tank, the aeration reaction tank is used for receiving the color coating wastewater, and the first aerator is used for performing micro-pore aeration on the color coating wastewater so as to float grease in the color coating wastewater.

Optionally, the oil removing device includes an inclined tube oil separation tank and a first chemical feeding pump, the inclined tube oil separation tank is communicated with the aeration device, and the first chemical feeding pump is used for adding the first chemical into the inclined tube oil separation tank.

Optionally, the first agent is a degreasing flocculant.

Optionally, the oil removing device further comprises a regulating reservoir and a second aerator arranged in the regulating reservoir, the regulating reservoir is communicated with the inclined tube oil separation tank, and the second aerator is used for performing micro-pore aeration on the color coating wastewater to remove part of COD and ammonia nitrogen.

Optionally, the precipitation device includes that pump, second grade are thrown to the pump and the one-level vortex flow reactor, second grade vortex flow reactor and the pipe chute settler that communicate in order, the one-level vortex flow reactor with deoiling device intercommunication, the one-level is thrown the pump be used for to throw in the one-level vortex flow reactor and remove oil agent and stabilizer, the second grade throw the pump be used for to throw in the second grade vortex flow reactor and throw polyacrylamide and form alum blossom, the pipe chute settler be used for with alum blossom deposits, obtains the second treatment fluid.

Optionally, filter equipment is including the one-level filtering ponds, middle pond, elevator pump, second grade filtering ponds and the circulating pump that communicate in order, the one-level filtering ponds play water and flow extremely middle pond, solution in the middle pond passes through the elevator pump is carried to the second grade filtering ponds, clear liquid in the second grade filtering ponds passes through the circulating pump flow direction reverse osmosis water treatment facilities.

Optionally, reverse osmosis water treatment facilities is including ultrafiltration equipment, one-level RO equipment, second grade RO equipment, tertiary RO equipment and the DTRO equipment that communicates in order, the clear liquid warp the ultrafiltration equipment filters the back and gets into one-level RO equipment, the dense water after the one-level RO equipment is handled gets into second grade RO equipment, the dense water after the second grade RO equipment is handled gets into tertiary RO equipment, the dense water after the tertiary RO equipment is handled gets into the DTRO equipment, the dense water after the DTRO equipment is handled gets into evaporation crystallization device.

Optionally, the reverse osmosis water treatment device further comprises a pure water tank, and the clean water treated by the primary RO device, the secondary RO device, the tertiary RO device and the DTRO device enters the pure water tank.

In order to achieve the above object, according to a second aspect of the present invention, there is also provided a color coating wastewater treatment method, comprising the steps of:

carrying out micropore aeration on the color coating wastewater;

adding a first medicament into the color coating wastewater for flocculation and precipitation to generate oleophilic floccules, and removing oil by an air floatation method to obtain a first treatment liquid;

adding a second medicament into the first treatment liquid for flocculation and precipitation to form alum floc to obtain a second treatment liquid;

filtering the second treatment solution to obtain clear solution;

carrying out reverse osmosis pretreatment, primary reverse osmosis water treatment, secondary reverse osmosis water treatment, tertiary reverse osmosis water treatment and disc tube type reverse osmosis water treatment on the clear liquid in sequence to obtain concentrated water;

and evaporating and concentrating the concentrated water to obtain salt residue and pure water.

The invention provides a color-coated wastewater treatment system and a treatment method, which are characterized in that through carrying out micro-porous aeration, flocculation precipitation and filtration on color-coated wastewater, grease, COD (chemical oxygen demand) and ammonia nitrogen in the color-coated wastewater are effectively removed, and then salt residue and pure water are obtained through multi-stage reverse osmosis water treatment combined with evaporation concentration, so that zero discharge treatment of the color-coated wastewater and recycling of resources are realized.

Drawings

It will be appreciated by those skilled in the art that the drawings are provided for a better understanding of the invention and do not constitute any limitation to the scope of the invention. Wherein:

FIG. 1 is a schematic view of a color-coating wastewater treatment system according to an embodiment of the present invention;

FIG. 2 is a step diagram of a method for treating wastewater from color painting according to an embodiment of the present invention;

in the drawings:

10-an aeration device; 11-an aeration reaction tank; 12-a first aerator; 20-an oil removal device; 21-inclined tube oil separation tank; 22-a first dosing pump; 23-an oil collecting tank; 24-a regulating reservoir; 25-a second aerator; 30-a precipitation device; 31-first-stage feeding pump; 32-second-stage feeding pump; 33-a first vortex flow reactor; 34-a two-stage vortex flow reactor; 35-inclined tube precipitator; 40-a filtration device; 41-first-stage filtering tank; 42-an intermediate tank; 43-a secondary filtering tank; 50-reverse osmosis water treatment device; 51-ultrafiltration equipment; 52-primary RO device; 53-secondary RO devices; 54-a tertiary RO plant; a 55-DTRO device; 60-evaporative crystallization device.

Detailed Description

To further clarify the objects, advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is to be noted that the drawings are in greatly simplified form and are not to scale, but are merely intended to facilitate and clarify the explanation of the embodiments of the present invention. Further, the structures illustrated in the drawings are often part of actual structures. In particular, the drawings may have different emphasis points and may sometimes be scaled differently.

As used in this application, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this disclosure, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise. As used in this disclosure, the term "plurality" is generally employed in its sense including "at least one" unless the content clearly dictates otherwise. As used in this disclosure, the term "at least two" is generally employed in a sense including "two or more" unless the content clearly dictates otherwise. Furthermore, the terms "first", "second", "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", "third" may explicitly or implicitly include one or at least two of the features.

As shown in fig. 1, fig. 1 is a schematic view of a color-coating wastewater treatment system according to an embodiment of the present invention. The embodiment provides a waste water treatment system is scribbled to coloured silk, including aeration equipment 10, deoiling device 20, sediment device 30, filter equipment 40, reverse osmosis water treatment facilities 50 and the evaporation crystallization device 60 that communicate in order, wherein:

the aeration device 10 is used for carrying out micropore aeration on the color coating wastewater;

the oil removing device 20 is used for adding a first medicament into the color coating wastewater for flocculation and precipitation to generate oleophilic floccules, and removing grease by an air floatation method to obtain a first treatment liquid;

the precipitation device 30 is configured to add a second reagent to the first treatment solution to perform flocculation precipitation and form alum flocs, so as to obtain a second treatment solution;

the filtering device 40 is configured to filter the second treatment liquid to obtain a clear liquid;

the reverse osmosis water treatment device 50 is used for sequentially carrying out reverse osmosis pretreatment, primary reverse osmosis water treatment, secondary reverse osmosis water treatment, tertiary reverse osmosis water treatment and disc tube type reverse osmosis water treatment on the clear liquid to obtain concentrated water;

and the evaporative crystallization device 60 is used for carrying out evaporative concentration on the concentrated water to obtain salt slag and pure water.

Specifically, the color-coating wastewater treatment system provided by this embodiment is mainly used for treating color-coating wastewater, the color-coating wastewater is from pretreatment, cleaning, water quenching and other working sections in the production of color-coated steel plates, the color-coating wastewater is alkaline oil-containing and high-COD wastewater, and in order to realize the comprehensive utilization of wastewater and achieve the emission reduction zero-emission target, grease, COD and salt in the color-coating wastewater need to be removed. The waste water treatment system is scribbled to coloured silk that this embodiment provided can reform transform on original waste water treatment equipment, also can build at new factory, and this application does not do any restriction to this.

With reference to fig. 1, the aeration device 10 includes an aeration reaction tank 11 and a first aerator 12 disposed in the aeration reaction tank 11, wherein the aeration reaction tank 11 is configured to receive the color coating wastewater, and the first aerator 12 is configured to perform micro-pore aeration on the color coating wastewater to float grease in the color coating wastewater. In this embodiment, the aeration reaction tank 11 is, for example, a rotary diaphragm reaction tank, and the first aerator 12 is, for example, a tubular aerator or a microporous aeration disk, which is not limited in any way by the present application.

Referring to fig. 1, the oil removing device 20 includes an inclined tube oil separation tank 21 and a first chemical feeding pump 22, the inclined tube oil separation tank 21 is communicated with the aeration device 10, and the first chemical feeding pump 22 is configured to feed the first chemical into the inclined tube oil separation tank 21. In this embodiment, the inclined tube oil separation tank 21 is communicated with the aeration reaction tank 11, the color coating wastewater in the aeration reaction tank 11 flows to the inclined tube oil separation tank 21 through siphon, the first dosing pump 22 doses the chemicals to make the color coating wastewater flocculate and precipitate preliminarily, the grease floats to the water surface to form floating oil, the floating oil is blocked on the surface of the inclined tube oil separation tank 21, and the floating oil can be discharged to the oil collecting tank 23 through a pipeline and transported outside. In this embodiment, the first agent is a degreasing flocculant. The oil-removing flocculant is a novel high-molecular compound, has strong coagulation, adsorption and sedimentation properties, can treat wastewater with high oil content, has good removal rate to SS, COD, BOD, chroma and microorganisms in water, is a quick, high-efficiency and multifunctional special flocculant, and has strong adaptability to pH, temperature, turbidity, organic matters and the like of raw water. In the embodiment, the sludge generated by the inclined tube oil separation tank 21 can be treated in a harmless way by external transportation after being subjected to filter pressing by sludge filter pressing equipment. And (4) the sludge filtrate enters a regulating tank and is purified by a subsequent treatment unit.

With reference to fig. 1, the oil removing apparatus 20 further includes an adjusting tank 24 and a second aerator 25 disposed in the adjusting tank 24, the adjusting tank 24 is communicated with the inclined tube oil separation tank 21, and the second aerator 25 is configured to perform micro-porous aeration on the color coating wastewater to remove a portion of COD and ammonia nitrogen. In this embodiment, the adjusting tank 24 is communicated with the inclined tube oil separation tank 21, the effluent of the inclined tube oil separation tank 21 is collected by the effluent tank and flows to the adjusting tank 24, and the adjusting tank 24 is aerated by the micro-pores again to remove part of COD and ammonia nitrogen. Similarly, the second aerator 25 is, for example, a pipe aerator or a microporous aeration disk, which is not limited in any way by the present application.

With reference to fig. 1, the precipitation device 30 includes a first-stage feeding pump 31, a second-stage feeding pump 32, and a first-stage vortex flow reactor 33, a second-stage vortex flow reactor 34, and an inclined tube precipitator 35 that are sequentially communicated, the first-stage vortex flow reactor 33 is communicated with the oil removal device 20, the first-stage feeding pump 31 is configured to feed an oil removal agent and a stabilizer into the first-stage vortex flow reactor 33, the second-stage feeding pump 32 is configured to feed polyacrylamide into the second-stage vortex flow reactor 34 to form alum flocs, and the inclined tube precipitator 35 is configured to precipitate the alum flocs to obtain the second treatment solution.

In this embodiment, the primary vortex flow reactor 33 is communicated with the regulating reservoir 24, the first treatment liquid in the regulating reservoir 24 is lifted to the primary vortex flow reactor 33 by a lift pump, and the first treatment liquid automatically flows into the secondary vortex flow reactor 34 after the degreasing agent and the stabilizing agent are added to the primary vortex flow reactor 33; and adding polyacrylamide into the secondary vortex flow reactor 34 to further form large and compact alum flocs, wherein the effluent of the secondary vortex flow reactor 34 automatically flows into the inclined tube precipitator 35, and the inclined tube precipitator 35 is used for precipitating alum floc particles into the bottom of the tank to clarify water and obtain a second treatment solution. The oil removing agent is, for example, an inorganic polymer flocculant, and the stabilizer is, for example, attapulgite clay powder, which is not limited in any way by the present application. By arranging the two-stage vortex flow reactor, the oil removing and precipitating effects are better.

Referring to fig. 1, the filtering device 40 includes a first filtering tank 41, an intermediate tank 42, a lift pump, a second filtering tank 43 and a circulating pump, which are sequentially connected, wherein the effluent of the first filtering tank 41 automatically flows to the intermediate tank 42, the solution in the intermediate tank 42 is delivered to the second filtering tank 43 through the lift pump, and the clear liquid in the second filtering tank 43 flows to the reverse osmosis water treatment device 50 through the circulating pump. The primary filtering tank 41 is communicated with the inclined tube precipitator 35, and the second treatment liquid is conveyed to the reverse osmosis water treatment device 50 through a circulating pump after sequentially passing through the primary filtering tank 41, the intermediate tank 42 and the secondary filtering tank 43.

Referring to fig. 1, the reverse osmosis water treatment apparatus 50 includes an ultrafiltration apparatus 51, a first RO (reverse osmosis water treatment) apparatus 52, a second RO apparatus 53, a third RO apparatus 54, and a DTRO (disc tube reverse osmosis water treatment) apparatus 55, which are connected in sequence, wherein the clear liquid is filtered by the ultrafiltration apparatus 51 and then enters the first RO apparatus 52, the concentrated water treated by the first RO apparatus 52 enters the second RO apparatus 53, the concentrated water treated by the second RO apparatus 53 enters the third RO apparatus 54, the concentrated water treated by the third RO apparatus 54 enters the DTRO apparatus 55, and the concentrated water treated by the DTRO apparatus 55 enters the evaporative crystallization apparatus 60.

The clear solution is treated by the ultrafiltration device 51, the effluent enters the primary RO device 52, the clear water treated by the primary RO device 52 is used by a workshop or enters a pure water tank, the treated concentrated water enters the secondary RO device 53, the clear water treated by the secondary RO device 53 enters the pure water tank, the treated concentrated water enters the tertiary RO device 54, the clear water treated by the tertiary RO device 54 enters the pure water tank, and the treated concentrated water enters the DTRO device 55 for further treatment to obtain the concentrated water.

The strong brine treated by the DTRO equipment 55 enters the evaporation crystallization device 60, the effluent of the evaporation crystallization device 60 enters the pure water tank, the salt slag is transported outside for disposal, and the desalted mother liquor flows back to the water inlet end of the evaporation crystallization device 60. Therefore, the desalting treatment of the color coating wastewater is completed, and the zero discharge target is realized. In this embodiment, the evaporative crystallization device 60 is a triple-effect multi-stage evaporator.

This embodiment is through being used for circulating water system's side with reverse osmosis water treatment facilities 50 and straining, and the desalinized water after the side is strained partly is used for production, and partly return circulating water system (pure water case), and the water after the waste water treatment is scribbled in production is directly used for the make-up water of circulating water to realize system water balance, reduced investment cost.

Based on this, this embodiment further provides a color coating wastewater treatment method, and fig. 2 is a step diagram of the color coating wastewater treatment method provided in the embodiment of the present invention, where the color coating wastewater treatment method includes the following steps:

s1, carrying out micropore aeration on the color coating wastewater;

s2, adding a first medicament into the color coating wastewater to perform flocculation and precipitation to generate oleophilic floccules, and removing oil by an air floatation method to obtain a first treatment liquid;

s3, adding a second medicament into the first treatment liquid for flocculation and precipitation to form alum floc to obtain a second treatment liquid;

s4, filtering the second treatment solution to obtain clear liquid;

s5, sequentially carrying out reverse osmosis pretreatment, primary reverse osmosis water treatment, secondary reverse osmosis water treatment, tertiary reverse osmosis water treatment and disc tube type reverse osmosis water treatment on the clear liquid to obtain concentrated water;

and S6, evaporating and concentrating the concentrated water to obtain salt residue and pure water.

Through carrying out micropore aeration, flocculation and precipitation and filtration on the color coating wastewater, grease, COD (chemical oxygen demand) and ammonia nitrogen in the color coating wastewater are effectively removed, and then salt slag and pure water are obtained through multi-stage reverse osmosis water treatment combined with evaporation and concentration, so that zero emission treatment of the color coating wastewater and recycling of resources are realized.

To sum up, the embodiment of the invention provides a color coating wastewater treatment system and a treatment method, wherein the treatment system comprises an aeration device, an oil removal device, a precipitation device, a filtering device, a reverse osmosis water treatment device and an evaporation crystallization device which are sequentially communicated, wherein: the aeration device is used for carrying out micropore aeration on the color coating wastewater; the oil removing device is used for adding a first medicament into the color coating wastewater for flocculation and precipitation to generate oleophilic floccules, and removing grease by an air floatation method to obtain a first treatment liquid; the precipitation device is used for adding a second medicament into the first treatment liquid for flocculation precipitation to form alum floc so as to obtain a second treatment liquid; the filtering device is used for filtering the second treatment liquid to obtain clear liquid; the reverse osmosis water treatment device is used for sequentially carrying out reverse osmosis pretreatment, primary reverse osmosis water treatment, secondary reverse osmosis water treatment, tertiary reverse osmosis water treatment and disc tube type reverse osmosis water treatment on the clear liquid to obtain concentrated water; and the evaporative crystallization device is used for carrying out evaporative concentration on the concentrated water to obtain salt slag and pure water. Through carrying out micropore aeration, flocculation and precipitation and filtration on the color coating wastewater, grease, COD (chemical oxygen demand) and ammonia nitrogen in the color coating wastewater are effectively removed, and then salt slag and pure water are obtained through multi-stage reverse osmosis water treatment combined with evaporation and concentration, so that zero emission treatment of the color coating wastewater and recycling of resources are realized.

It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. It will be apparent to those skilled in the art from this disclosure that many changes and modifications can be made, or equivalents modified, in the embodiments of the invention without departing from the scope of the invention. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the protection scope of the technical solution of the present invention, unless the content of the technical solution of the present invention is departed from.

Claims (10)

1. The utility model provides a waste water treatment system is scribbled to coloured silk, its characterized in that, including aeration equipment, deoiling device, the sediment device, filter equipment, reverse osmosis water treatment facilities and the evaporation crystallization device that communicates in order, wherein:

the aeration device is used for carrying out micropore aeration on the color coating wastewater;

the oil removing device is used for adding a first medicament into the color coating wastewater for flocculation and precipitation to generate oleophilic floccules, and removing grease by an air floatation method to obtain a first treatment liquid;

the precipitation device is used for adding a second medicament into the first treatment liquid for flocculation precipitation to form alum floc so as to obtain a second treatment liquid;

the filtering device is used for filtering the second treatment liquid to obtain clear liquid;

the reverse osmosis water treatment device is used for sequentially carrying out reverse osmosis pretreatment, primary reverse osmosis water treatment, secondary reverse osmosis water treatment, tertiary reverse osmosis water treatment and disc tube type reverse osmosis water treatment on the clear liquid to obtain concentrated water;

and the evaporative crystallization device is used for carrying out evaporative concentration on the concentrated water to obtain salt slag and pure water.

2. The wastewater treatment system for color coating according to claim 1, wherein the aeration device comprises an aeration reaction tank and a first aerator arranged in the aeration reaction tank, the aeration reaction tank is used for receiving the wastewater for color coating, and the first aerator is used for carrying out micro-pore aeration on the wastewater for color coating so as to float the grease in the wastewater for color coating.

3. The wastewater treatment system for color coating according to claim 1, wherein the oil removal device comprises a chute oil trap and a first dosing pump, the chute oil trap is communicated with the aeration device, and the first dosing pump is used for adding the first chemical into the chute oil trap.

4. The color-coated wastewater treatment system according to claim 1 or 3, wherein the first agent is an oil-removing flocculant.

5. The color-coating wastewater treatment system according to claim 3, wherein the oil removal device further comprises a regulating reservoir and a second aerator arranged in the regulating reservoir, the regulating reservoir is communicated with the inclined-tube oil separation tank, and the second aerator is used for carrying out micro-pore aeration on the color-coating wastewater to remove part of COD and ammonia nitrogen.

6. The color-coated wastewater treatment system according to claim 1, wherein the precipitation device comprises a primary feeding pump, a secondary feeding pump, and a primary vortex flow reactor, a secondary vortex flow reactor and an inclined tube precipitator which are sequentially communicated, the primary vortex flow reactor is communicated with the oil removal device, the primary feeding pump is used for feeding an oil removal agent and a stabilizer into the primary vortex flow reactor, the secondary feeding pump is used for feeding polyacrylamide into the secondary vortex flow reactor and forming alum flocs, and the inclined tube precipitator is used for precipitating the alum flocs to obtain the second treatment solution.

7. The wastewater treatment system for color coating according to claim 1, wherein the filtration device comprises a primary filtration tank, an intermediate tank, a lift pump, a secondary filtration tank and a circulation pump, which are connected in sequence, wherein the effluent of the primary filtration tank flows to the intermediate tank, the solution in the intermediate tank is conveyed to the secondary filtration tank through the lift pump, and the clear solution in the secondary filtration tank flows to the reverse osmosis water treatment device through the circulation pump.

8. The wastewater treatment system for color coating according to claim 1, wherein the reverse osmosis water treatment device comprises an ultrafiltration device, a primary RO device, a secondary RO device, a tertiary RO device and a DTRO device which are sequentially communicated, the clear liquid is filtered by the ultrafiltration device and then enters the primary RO device, the concentrated water treated by the primary RO device enters the secondary RO device, the concentrated water treated by the secondary RO device enters the tertiary RO device, the concentrated water treated by the tertiary RO device enters the DTRO device, and the concentrated water treated by the DTRO device enters the evaporative crystallization device.

9. The wastewater treatment system for color painting according to claim 8, wherein the reverse osmosis water treatment apparatus further comprises a purified water tank, and the clean water treated by the primary RO device, the secondary RO device, the tertiary RO device and the DTRO device enters the purified water tank.

10. A color coating wastewater treatment method is characterized by comprising the following steps:

carrying out micropore aeration on the color coating wastewater;

adding a first medicament into the color coating wastewater for flocculation and precipitation to generate oleophilic floccules, and removing oil by an air floatation method to obtain a first treatment liquid;

adding a second medicament into the first treatment liquid for flocculation and precipitation to form alum floc to obtain a second treatment liquid;

filtering the second treatment solution to obtain clear solution;

carrying out reverse osmosis pretreatment, primary reverse osmosis water treatment, secondary reverse osmosis water treatment, tertiary reverse osmosis water treatment and disc tube type reverse osmosis water treatment on the clear liquid in sequence to obtain concentrated water;

and evaporating and concentrating the concentrated water to obtain salt residue and pure water.

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