System and method for treating and recycling leveling liquid-containing wastewater of cold rolling leveling unit

Abstract

The invention discloses a system for purifying, collecting and recycling temper lubricant-containing wastewater. The system comprises a wastewater collecting tank of a temper mill, the system is characterized by comprising a wastewater collection automatic valve, a transfer water tank, a feed pump, a circulating tank, a circulating pump, a silicon carbide ceramic membrane assembly, a backwashing storage tank, a backwashing tank, a chemical cleaning tank, a middle water tank, a reverse osmosis high-pressure pump, an RO (reverse osmosis) assembly, a desalted water production water tank, a water production pump and necessary instruments. The invention also discloses a method for recycling the leveling-containing waste liquid by using the system. According to the invention, the characteristics of high filtration precision and strong pollution resistance of the silicon carbide ceramic membrane are utilized to pretreat the wastewater and remove solid impurities, bacteria, microorganisms and grease in the wastewater, and the characteristic of high precision of the reverse osmosis membrane is utilized to further control ions in the wastewater and reduce the conductivity of the wastewater, so that the wastewater is finally turned into wealth to achieve the purpose of recycling. The method has the characteristics of good treatment effect, simple equipment process, less later maintenance, low treatment cost and the like.

Description

Technical Field

[0001] The present invention relates to the field of recycling and purification treatment of production wastewater in the cold rolling temper mill of the metallurgical industry, and specifically relates to a complete set of systems for collecting, purifying and recycling wastewater containing tempering liquid in a cold rolling temper mill, and also relates to a recycling method. Background Art

[0002] In the production process of the cold rolling process of metallurgical enterprises, temper mills are available in process sections such as continuous annealing and hot dip galvanizing. The current temper mills all adopt wet tempering, and use demineralized water (conductivity < 10 us / cm), demineralized water + tempering liquid as the tempering medium. The tempering medium is in a non-recycling mode, that is, the demineralized water and tempering liquid in the tempering section are not recycled after use, and are discharged to the wastewater treatment station for treatment after being used once. In this mode, the usage amounts of demineralized water and tempering liquid, as well as the wastewater treatment amount, are relatively large. It is one of the main water consumption points and wastewater points in the continuous annealing and hot dip galvanizing units. The conductivity of this part of the wastewater is not high, and there are still active ingredients in the tempering liquid. The wastewater and waste liquid still have utilizable value. Direct discharge not only causes waste of resources but also increases the wastewater treatment cost.

[0003] The main pollutants in the wastewater of the temper mill are a small amount of metal particles such as iron powder and zinc powder brought in from the steel plate surface, and they exist in solid form. The main pollutants in the wastewater are zinc powder microparticles, iron powder microparticles, and a small amount of oil components including lubricating grease and surfactants mechanically brought in. The particle sizes are all extremely small, belonging to micro- and nano-scale particles. Micro zinc powder has the property of self-aggregation and certain adhesiveness, and aggregates and pollutes the water quality in the water body mixed with micro iron powder, micro oil content, and micro dust. When the tempering liquid needs to be used in the unit production, a large amount of tempering liquid will also enter the wastewater, resulting in a large amount of zinc- and iron-containing oil sludge in this part of the wastewater, which cannot be directly recycled. Summary of the Invention

[0004] Therefore, in order to make up for the above deficiencies, the present invention provides a purification, collection and recycling system for wastewater containing tempering liquid. Another problem to be solved by the present invention is to provide a method for treating wastewater containing tempering liquid in a cold rolling temper mill by using the recycling system.

[0005] The technical solution of the present invention is a purification, collection and recycling system for wastewater containing tempering liquid, including a wastewater collection tank of a temper mill. The system includes a wastewater collection automatic valve, a transfer storage tank, a feeding pump, a circulation tank, a circulation pump, a silicon carbide ceramic membrane module, a backwashing storage tank, a backwashing tank, a chemical cleaning tank, an intermediate water tank, a reverse osmosis high-pressure pump, an RO reverse osmosis module, a demineralized water production tank, a product water pump, and necessary instruments;

[0006] The automatic waste water collection valve is located below the waste water collection tank and is connected to the transfer water tank. A sludge discharge port is provided at the lower end of the transfer water tank. The inlet end of the feeding pump is communicated with the outlet of the transfer water tank, and the outlet end of the feeding pump is connected to the top of the circulation tank. The circulation tank is connected to a silicon carbide membrane module through a circulation pump. The silicon carbide membrane module is connected to a silicon carbide main machine, and the silicon carbide membrane module is connected to the circulation tank. The silicon carbide membrane module is connected to a chemical cleaning tank.

[0007] The chemical cleaning tank is connected to an intermediate water tank. On the connecting pipeline between the intermediate water tank and the chemical cleaning tank, it is connected to the silicon carbide membrane module. The intermediate water tank is connected to a reverse osmosis device through a reverse osmosis high-pressure pump, and the reverse osmosis device is connected to the demineralized water production tank. The outlet of the demineralized water production tank is connected to a demineralized water production water pump, which is connected to a planishing machine. The reverse osmosis device includes a reverse osmosis module and an RO reverse osmosis main machine. On the connecting pipeline between the chemical cleaning tank and the intermediate water tank, a backwashing tank is connected.

[0008] An automatic waste water collection valve is provided below the waste water collection tank; a sludge discharge valve is provided below the transfer water tank; a continuous overflow concentrated flowmeter and an overflow regulating valve are provided on the circulation tank.

[0009] One end of the circulation pump is connected to the silicon carbide ceramic membrane module, and the other end of the silicon carbide ceramic membrane module is connected to the top of the circulation tank. A water production outlet is communicated with the silicon carbide ceramic membrane module, and a sampling valve is provided at the lower part of the silicon carbide ceramic membrane module.

[0010] The inlet end of the high-pressure pump is communicated with the outlet of the intermediate water tank, the outlet end of the high-pressure pump is connected to the RO reverse osmosis membrane module, and a valve and an inlet pressure gauge are installed between the connecting pipeline of the high-pressure pump and the RO reverse osmosis membrane module.

[0011] For a purification, collection and reuse system of waste water containing leveling liquid according to the present invention, preferably, the silicon carbide ceramic membrane module includes a shell and a silicon carbide ceramic membrane inside; the RO reverse osmosis membrane module includes a shell and an RO reverse osmosis membrane inside. For the silicon carbide ceramic membrane module, the shell is made of stainless steel or fiberglass, and a silicon carbide ceramic membrane element is fixed inside. For the RO reverse osmosis membrane module, the shell is made of fiberglass, and an aromatic polyamide reverse osmosis membrane element is inside.

[0012] Further, multiple silicon carbide ceramic membranes can be installed in the silicon carbide ceramic membrane module according to requirements, and the silicon carbide ceramic membranes can be arranged in multiple groups in series and parallel. Further, multiple RO reverse osmosis membranes can be installed in the RO reverse osmosis membrane module according to requirements. The RO reverse osmosis membranes can be arranged in multiple groups in series and parallel.

[0013] A purification, collection and reuse system for leveling liquid-containing wastewater according to the present invention. Preferably, the bottom of the transfer water tank is of a conical structure; an overflow discharge port is provided at the top of the transfer water tank; the overflow discharge port is communicated with the pipeline at the outlet of the sludge discharge valve.

[0014] A purification, collection and reuse system for leveling liquid-containing wastewater according to the present invention. Preferably, an inlet regulating valve and an inlet flowmeter are installed between the connecting pipeline of the feeding pump and the circulation tank.

[0015] A purification, collection and reuse system for leveling liquid-containing wastewater according to the present invention. Preferably, a circulation pump inlet valve is installed on the connecting pipeline between the lower part of the circulation tank and the circulation pump; a circulation pump outlet valve and an inlet pressure gauge are installed between the connecting pipeline of the silicon carbide ceramic membrane module and the circulation pump; a water production outlet is communicated and arranged on the side wall of the silicon carbide ceramic membrane module, and a manual sampling valve is installed at the lower part of the silicon carbide ceramic membrane module; a water production manual valve, a water production pressure gauge, a backwashing storage tank, a water production regulating valve, a water production flowmeter and a water production automatic valve are successively installed between the connecting pipeline of the silicon carbide ceramic membrane module and the water production outlet, and a chemical cleaning automatic valve F1 is installed on the connecting pipeline between the water production outlet and the chemical cleaning tank.

[0016] A purification, collection and reuse system for leveling liquid-containing wastewater according to the present invention. Preferably, a return water pressure gauge, a return flow regulating valve and a return flowmeter are successively installed between the connecting pipeline of the silicon carbide ceramic membrane module and the circulation tank; a backwashing automatic valve F5 is installed at the top of the backwashing tank.

[0017] Furthermore, the backwashing automatic valve F5 is communicated with a compressed air pipeline.

[0018] A purification, collection and reuse system for leveling liquid-containing wastewater according to the present invention. Preferably, the transfer water tank, the circulation tank, the demineralized water production tank, the chemical cleaning tank, the silicon carbide membrane module, the intermediate water tank and the reverse osmosis device are all connected with a wastewater pit.

[0019] The present invention also provides a method for treating leveling liquid-containing wastewater by the above purification, collection and reuse system for leveling liquid-containing wastewater. Using the above reuse system, the method includes the following steps:

[0020] (1) Start the feeding pump. The wastewater from the leveling machine to be treated enters the feeding pump through the transfer water tank and is pressurized and then enters the circulation tank. After the wastewater from the leveling machine reaches a certain liquid level in the circulation tank, open the corresponding valve. The wastewater from the leveling machine to be treated enters the circulation pump from the circulation tank, is pressurized and then enters the silicon carbide ceramic membrane module, and returns to the circulation tank from the other end of the silicon carbide ceramic membrane module;

[0021] (2) After the circulating pump runs stably, open the corresponding valve. Under the action of pressure, the purified wastewater from the temper mill flows out from the water outlet of the silicon carbide ceramic membrane module to the intermediate water tank and the chemical cleaning tank. When the pollutants accumulate to a certain amount on the filtration surface of the silicon carbide ceramic membrane, at this time, turn off the circulating pump, close the automatic water production valve, open the automatic backwashing valve, and the gas source enters and squeezes the backwashing water in the backwashing tank, and injects it into the silicon carbide ceramic membrane module to backwash the membrane surface;

[0022] (3) When the membrane flux of the silicon carbide ceramic membrane module decreases and cannot be restored after backwashing, the system stops running. Manually prepare the liquid and add chemical cleaning agents into the chemical cleaning tank. The chemical cleaning agent solution is pressurized by the chemical cleaning pump and sent to the silicon carbide ceramic membrane module, and returns to the chemical cleaning tank through the automatic valve to circulate and clean the silicon carbide ceramic membrane module;

[0023] (4) The wastewater from the temper mill enters the intermediate water tank after removing impurities through the silicon carbide ceramic membrane system, and then enters the reverse osmosis device. The water produced by the RO reverse osmosis membrane system enters the demineralized water production tank through the water production regulating valve. The production tank is equipped with on-line conductivity monitoring; when the conductivity of the demineralized water production is qualified, the demineralized water production is sent to the tempering water tank for use through the demineralized water production pump and the automatic valve.

[0024] The gas source is the compressed air provided on-site. When the backwashing tank does not backwash, it stores part of the produced water in the tank body. When backwashing is required, the instant release of compressed air will form a steam-water mixture with a certain pressure and reverse-press it into the silicon carbide ceramic membrane to achieve the purpose of cleaning the pollutants in the membrane channel and disturbing the accumulation of pollutants.

[0025] In the treatment method of the present invention, preferably, the operating temperature of the reverse osmosis membrane device is 5 - 40 °C; preferably, in step (4), when the conductivity exceeds the preset value, the system prompts an alarm, and the original demineralized water make-up water system is retained. When the reuse system equipment is abnormal, it does not affect the main line production.

[0026] Beneficial effects:

[0027] The present invention provides a purification, collection and reuse system for wastewater containing tempering liquid. This system uses membrane separation technology to remove solid impurities, bacteria, microorganisms, oils and fats in the wastewater and control the conductivity, and meets the reuse standard. The present invention uses the characteristics of high filtration accuracy and strong anti-fouling ability of the silicon carbide ceramic membrane to pre-treat the wastewater, remove solid impurities, bacteria, microorganisms, oils and fats in the wastewater, and then uses the characteristics of high precision of the reverse osmosis membrane to further control the ions in the wastewater, reduce the conductivity of the wastewater, and finally the wastewater "turns waste into treasure" to achieve the purpose of recycling. The present invention has the characteristics of good treatment effect, simple equipment process, less later maintenance and low treatment cost.

[0028] The present invention enhances the characteristics of the silicon carbide membrane itself through a special operation mode in the application of treating wastewater containing leveling liquid. The invention mainly uses a water pump with a large flow rate and high pressure to circulate the wastewater containing leveling liquid at a high speed in the silicon carbide membrane module, so that the wastewater quickly passes through the membrane channel during the circulation process, forming a special in-membrane circulation mode, and at the same time controlling the outlet pressure to be maintained in a relatively high environment. In this way, the wastewater containing pollutants such as leveling liquid, solid impurities, microorganisms, bacteria and grease quickly passes through the membrane channel, making full use of the mechanical strength of the silicon carbide ceramic membrane itself to support the channel, and using its excellent hydrophilic property to "absorb" the water in the circulating wastewater and permeate through the membrane. In this way, even when the filtration accuracy of the membrane itself is not high, a very high filtration effect can still be achieved, and the accumulation of pollutants on the membrane filtration layer is greatly slowed down, and the requirement for the quality of the incoming water is also greatly reduced, and the final water production effect remains unchanged. In the application of wastewater containing leveling liquid, the present invention further reduces the wastewater treatment process. Finally, when the conductivity of the incoming water exceeds the preset value, it enters the RO reverse osmosis equipment for filtration, and the redundant ions in the wastewater are further removed by using the working principle of the RO reverse osmosis equipment, and the finally qualified produced water is applied to the leveling water or other pure water consumption process sections. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic process flow diagram of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] As Figure 1 , a collection, purification and reuse system for wastewater containing leveling liquid, the system includes a wastewater collection automatic valve, a transfer storage tank, a feeding pump, a circulation tank, a circulation pump, a silicon carbide ceramic membrane module, a backwashing storage tank, a backwashing tank, a chemical cleaning tank, an intermediate water tank, a high-pressure pump, an RO reverse osmosis module, a demineralized water production tank and a demineralized water production water pump. The wastewater collection automatic valve is interlocked with the reuse system and the collection automatic valve is closed when the system is started, and the wastewater enters the transfer storage tank. When the reuse system is shut down or under maintenance, the collection automatic valve is opened and the wastewater is discharged back to the wastewater pit along the original path. The bottom of the transfer storage tank is of a conical structure, there is a sludge discharge valve at the bottom, and an online conductivity meter is installed in the transfer storage tank. The inlet end of the feeding pump is connected to the outlet of the transfer storage tank, the outlet end of the feeding pump is connected to the top of the circulation tank, and an inlet regulating valve and an inlet flow meter are installed between the connecting pipeline of the feeding pump and the circulation tank.

[0031] A continuous overflow thickening flowmeter and an overflow regulating valve are provided on the circulation tank. A circulation pump inlet valve is installed on the pipeline connecting the lower part of the circulation tank and the circulation pump. One end of the circulation pump is connected to the silicon carbide ceramic membrane module. A circulation pump outlet valve and an inlet pressure gauge are installed on the pipeline connecting the silicon carbide ceramic membrane module and the circulation pump. A water production outlet is communicated and arranged on the side wall of the module. A manual sampling valve is installed at the lower part of the membrane module. A water production manual valve, a water production pressure gauge, a backwashing storage tank, a water production regulating valve, a water production flowmeter and a water production automatic valve are successively installed on the pipeline connecting the silicon carbide ceramic membrane module and the water production outlet. A chemical cleaning automatic valve F1 is installed on the pipeline connecting the water production outlet and the chemical cleaning tank. The other end of the silicon carbide ceramic membrane module is connected to the top of the circulation tank. A return water pressure gauge, a return flow regulating valve and a return flowmeter are successively installed on the pipeline connecting the silicon carbide ceramic membrane module and the circulation tank. An anti-washing automatic valve F5 is installed on the top of the anti-washing tank. The automatic valve F5 is communicated with the compressed air pipeline.

[0032] In the above implementation process, check that all valves of the system are in the closed state. Open the inlet regulating valve and start the feeding pump. The waste water of the to-be-treated planisher passes through the transfer water tank, enters the feeding pump, and after the pressure is increased, enters the circulation tank. After the waste water of the planisher reaches a certain liquid level in the circulation tank, open the circulation pump inlet valve, the circulation pump outlet valve, the reflux automatic valve F4, and the return flow regulating valve. The waste water of the to-be-treated planisher enters the silicon carbide ceramic membrane module after being pressurized by the circulation pump from the circulation tank, and returns to the circulation tank from the other end of the silicon carbide ceramic membrane module. After the circulation pump runs stably, open the water production manual valve, the water production regulating valve, and the water production automatic valves F1 / F2. Under the action of pressure, the purified waste water of the planisher is output from the water production outlet of the silicon carbide ceramic membrane module to the intermediate water tank and the chemical cleaning tank (the automatic valve F1 is closed after the high liquid level of the chemical cleaning tank). The system circulation volume can be adjusted by adjusting the circulation pump outlet valve. The system operating pressure can be adjusted by adjusting the return flow regulating valve. The water production flow can be controlled by adjusting the water production flow regulating valve. When the pollutants are enriched on the filtration surface of the silicon carbide ceramic membrane to a certain amount, at this time, close the circulation pump, close the water production automatic valve, open the anti-washing automatic valve, the air source enters and squeezes the backwashing water in the backwashing storage tank and injects it into the silicon carbide ceramic membrane module to perform backwashing on the membrane surface, so as to wash away the filter cake layer attached to the membrane surface, thereby effectively preventing membrane fouling and ensuring the long-term stable operation of the system. After the waste water of the planisher is treated, the concentrated waste water of the planisher is stored in the circulation tank. By controlling the continuous overflow thickening flow rate, the waste water concentration in the circulation tank is maintained, and the automatic valve F7 is regularly opened for discharge according to this concentration or discharged to the waste water pit through the circulation continuous thickening valve.

[0033] When the membrane flux of the silicon carbide ceramic membrane module cannot be restored after backwashing, the system shuts down. Chemical cleaning agents are added to the chemical cleaning tank by manual liquid preparation. The outlet of the chemical cleaning tank is connected to the inlet of the chemical cleaning pump. The outlet automatic valve F6 of the chemical cleaning pump is opened, and the chemical cleaning agent preparation liquid is pressurized by the chemical cleaning pump and sent to the silicon carbide ceramic membrane module, and then returns to the chemical cleaning tank through the automatic valve F3 to circulate and clean the silicon carbide ceramic membrane module. After the chemical cleaning, the waste liquid is discharged to the wastewater pit through the automatic valve F8.

[0034] The wastewater from the planishing machine enters the intermediate water tank after removing suspended solids, bacteria, microorganisms and grease through the silicon carbide ceramic membrane system. The inlet end of the high-pressure pump is connected to the outlet of the intermediate water tank, and the outlet end of the high-pressure pump is connected to the RO reverse osmosis membrane module. Valves and an inlet pressure gauge are installed between the connecting pipeline of the high-pressure pump and the RO reverse osmosis membrane module. The RO reverse osmosis membrane system continuously discharges concentrated water to the wastewater pit by monitoring pressure and flow. The water produced by the RO reverse osmosis membrane system enters the demineralized water production tank through the produced water regulating valve, and the conductivity of the production tank is monitored online. When the conductivity of the demineralized water production is less than 10 us / cm and qualified, the demineralized water production is sent to the planishing water tank for use through the production water pump and the automatic valve F9. When the conductivity exceeds the preset value, the system prompts an alarm. The original demineralized water makeup system is reserved, and when the reuse system equipment is abnormal, it does not affect the main line production.

[0035] When the planishing unit uses the planishing liquid preparation for planishing, the central control signal of the planishing machine is transmitted to the reuse system. The reuse system controls the closing of the automatic valve F2 for the water produced by the silicon carbide membrane and the opening of the automatic valve F10 for the outlet of the planishing liquid preparation. The wastewater containing the planishing liquid is used as the planishing liquid preparation after removing suspended solids, bacteria, microorganisms and sludge through the silicon carbide ceramic membrane system, and is recycled to the planishing liquid preparation tank through the automatic valve F10 for the outlet of the planishing liquid preparation.

[0036] The planishing liquid reuse preparation is emptied as a whole through the reuse system after a planishing production cycle and is no longer recycled. The collection automatic valve opens to empty and flush the wastewater collection pipeline after receiving the system control signal. After completing the emptying and flushing work, it closes again to enter the next wastewater collection, purification and reuse cycle.

[0037] In a preferred embodiment, the silicon carbide ceramic membrane module includes a housing and a silicon carbide ceramic membrane inside. Multiple silicon carbide ceramic membranes can be installed in the silicon carbide ceramic membrane module according to requirements.

[0038] In a preferred embodiment, the silicon carbide ceramic membranes can be arranged in multiple series and parallel combinations.

[0039] In a preferred embodiment, the RO reverse osmosis membrane module includes a housing and an RO reverse osmosis membrane inside. Multiple RO reverse osmosis membranes can be installed in the RO reverse osmosis membrane module according to requirements.

[0040] In a preferred embodiment, the RO reverse osmosis membrane can be arranged in multiple groups in series and parallel.

[0041] Example 1

[0042] The silicon carbide ceramic membrane module is installed with 1 ceramic membrane. The system consists of 1 one-core membrane element. The inlet membrane pressure is 0.3 Mpa, the outlet membrane pressure is 0.03 Mpa, the pressure on the water production side is 0.1 Mpa, and the water production flow rate is 200 LMH.

[0043] The RO reverse osmosis membrane system is installed with 1 group of reverse osmosis membranes. The pressure on the concentrated water side is 1.1 Mpa, the water production flow rate is 80 L / h, and the concentrated water flow rate is 900 L / h.

[0044] Treatment effect:

[0045] Water quality analysis table

[0046] Analysis item Detection limit Inlet water Silicon carbide effluent Reverse osmosis effluent Turbidity (NTU) 0.001 40.2 0.209 - Conductivity (μS / cm) 0.01 22.4 23.1 2.77 Oil (mg / L) 0.06 24 21.7 (including leveling liquid) ＜0.06

[0047] Example 2

[0048] The silicon carbide ceramic membrane module is installed with 4 groups of 19-core ceramic membranes. The system consists of 1 one-core membrane element. The inlet membrane pressure is 0.3 Mpa, the outlet membrane pressure is 0.05 Mpa, the pressure on the water production side is 0.16 Mpa, and the water production flow rate is 5.6 m 3 / h.

[0049] The RO reverse osmosis membrane system is installed with 1 group of 3 six-core reverse osmosis membranes. The pressure on the concentrated water side is 1.3 Mpa, the water production flow rate is 4.8 m 3 / h, the concentrated water return flow rate is 4 m 3 / h, and the concentrated water discharge amount is 1 m 3 / h.

[0050] Treatment effect:

[0051] Water quality analysis table

[0052] Analysis item Detection limit Inlet water Silicon carbide effluent Reverse osmosis effluent Turbidity (NTU) 0.001 21 0.325 - Conductivity (μS / cm) 0.01 112 112 3.12 Oil (mg / L) 0.06 105 98 (including leveling liquid) ＜0.06

[0053] Example 3

[0054] The silicon carbide ceramic membrane module is installed with 6 groups of 19-core ceramic membranes. The system consists of 1 one-core membrane element. The inlet membrane pressure is 0.33 Mpa, the outlet membrane pressure is 0.04 Mpa, the pressure on the water production side is 0.17 Mpa, and the water production flow rate is 9.2 m 3 / h.

[0055] The RO reverse osmosis membrane system is installed with 1 group of 3 nine-core reverse osmosis membranes. The pressure on the concentrated water side is 1.3 Mpa, the water production flow rate is 7.9 m 3 / h, the concentrated water return flow rate is 8 m 3 / h, and the concentrated water discharge amount is 1.5 m3 / h.

[0056] Treatment effect:

[0057] Water quality analysis table

[0058] Analysis item Detection limit Inlet water Silicon carbide effluent Reverse osmosis effluent Turbidity (NTU) 0.001 17 0.187 - Conductivity (μS / cm) 0.01 86 87 2.07 Oil (mg / L) 0.06 76 64 (including leveling liquid) ＜0.06

Claims

1. A purification, collection and reuse system for leveling liquid-containing wastewater, including a wastewater collection tank of a leveling machine, characterized in that: The system includes an automatic wastewater collection valve, a transfer storage tank, a feeding pump, a circulation tank, a circulation pump, a silicon carbide ceramic membrane module, a backwashing storage tank, a backwashing tank, a chemical cleaning tank, an intermediate water tank, a reverse osmosis high-pressure pump, an RO reverse osmosis module, a demineralized water production tank, a product water pump, and necessary instruments; The automatic wastewater collection valve is located below the wastewater collection tank and is connected to the transfer storage tank. A sludge discharge port is provided at the lower end of the transfer storage tank. The inlet end of the feeding pump communicates with the outlet of the transfer storage tank, and the outlet end of the feeding pump is connected to the top of the circulation tank. The circulation tank is connected to the silicon carbide membrane module through a circulation pump. The silicon carbide membrane module is connected to a silicon carbide main unit, and the silicon carbide membrane module is connected to the circulation tank. The silicon carbide membrane module is connected to the chemical cleaning tank; The chemical cleaning tank is connected to the intermediate water tank. On the pipeline connecting the intermediate water tank and the chemical cleaning tank, it is connected to the silicon carbide membrane module. The intermediate water tank is connected to the reverse osmosis device through a reverse osmosis high-pressure pump, and the reverse osmosis device is connected to the demineralized water production tank. The outlet of the demineralized water production tank is connected to a demineralized water product water pump, which is connected to the planishing machine. The reverse osmosis device includes a reverse osmosis module and an RO reverse osmosis main unit. On the pipeline connecting the chemical cleaning tank and the intermediate water tank, a backwashing tank is connected; An automatic wastewater collection valve is provided below the wastewater collection tank; a sludge discharge valve is provided below the transfer storage tank; a continuous overflow concentrated flowmeter and an overflow regulating valve are provided on the circulation tank; One end of the circulation pump is connected to the silicon carbide ceramic membrane module, and the other end of the silicon carbide ceramic membrane module is connected to the top of the circulation tank. A product water outlet is communicated with the silicon carbide ceramic membrane module, and a sampling valve is provided at the lower part of the silicon carbide ceramic membrane module.

2. The purification, collection and reuse system for wastewater containing leveling liquid according to claim 1, wherein: The silicon carbide ceramic membrane module includes a housing and a silicon carbide ceramic membrane inside; the RO reverse osmosis membrane module includes a housing and an RO reverse osmosis membrane inside.

3. The purification, collection and reuse system for wastewater containing leveling liquid according to claim 1, characterized in that: The bottom of the transfer storage tank is of a conical structure; an overflow discharge port is provided at the top of the transfer storage tank; the overflow discharge port is communicated with the pipeline at the outlet of the sludge discharge valve.

4. A purification, collection and reuse system for wastewater containing leveling liquid according to claim 1, characterized in that: An inlet regulating valve and an inlet flowmeter are installed between the pipeline connecting the feeding pump and the circulation tank.

5. A purification, collection and reuse system for waste water containing leveling liquid according to claim 1, characterized in that: A circulation pump inlet valve is installed on the pipeline connecting the lower part of the circulation tank and the circulation pump; a circulation pump outlet valve and an inlet pressure gauge are installed between the pipeline connecting the silicon carbide ceramic membrane module and the circulation pump. A product water outlet is communicated with the side wall of the silicon carbide ceramic membrane module, and a manual sampling valve is installed at the lower part of the silicon carbide ceramic membrane module. Between the pipeline connecting the silicon carbide ceramic membrane module and the product water outlet, a product water manual valve, a product water pressure gauge, a backwashing storage tank, a product water regulating valve, a product water flowmeter, and a product water automatic valve are installed in sequence. A chemical cleaning automatic valve F1 is installed on the pipeline connecting the product water outlet and the chemical cleaning tank.

6. The purification, collection and reuse system for wastewater containing leveling liquid according to claim 1, wherein: A return water pressure gauge, a return flow regulating valve, and a return flowmeter are installed in sequence between the pipeline connecting the silicon carbide ceramic membrane module and the circulation tank; a backwashing automatic valve F5 is installed on the top of the backwashing tank.

7. A purification, collection and reuse system for wastewater containing leveling liquid, according to claim 6, wherein: The backwashing automatic valve F5 is communicated with the compressed air pipeline.

8. A purification, collection and reuse system for wastewater containing leveling liquid according to claim 1, characterized in that: The transfer water tank, circulation tank, demineralized water production tank, chemical cleaning tank, silicon carbide membrane module, intermediate tank, and reverse osmosis device are all connected to a wastewater sump.

9. A method for treating leveling agent-containing wastewater using the purification, collection and reuse system for leveling agent-containing wastewater described in claim 1, characterized in that: It includes the following steps: (1) Start the feed pump. The wastewater from the leveling machine to be treated enters the feed pump through the transfer water tank, and after the pressure is increased, it enters the circulation tank. After the wastewater from the leveling machine reaches a certain liquid level in the circulation tank, open the corresponding valve. The wastewater from the leveling machine to be treated enters the circulation pump from the circulation tank, and after the pressure is increased, it enters the silicon carbide ceramic membrane module and returns to the circulation tank from the other end of the silicon carbide ceramic membrane module; (2) After the circulation pump runs stably, open the corresponding valve. Under the action of pressure, the purified wastewater from the leveling machine is output from the water production port of the silicon carbide ceramic membrane module to the intermediate tank and the chemical cleaning tank. When the pollutants accumulate to a certain amount on the filtration surface of the silicon carbide ceramic membrane, at this time, turn off the circulation pump, close the automatic water production valve, open the automatic backwashing valve, and the gas source enters and squeezes the backwashing water in the backwashing tank, and injects it into the silicon carbide ceramic membrane module to perform backwashing on the membrane surface; (3) When the membrane flux of the silicon carbide ceramic membrane module cannot be restored after backwashing, the system stops. Manually prepare the liquid and add chemical cleaning agents into the chemical cleaning tank. The chemical cleaning agent solution is pressurized by the chemical cleaning pump and sent to the silicon carbide ceramic membrane module, and returns to the chemical cleaning tank through the automatic valve to circulate and clean the silicon carbide ceramic membrane module; (4) The wastewater from the leveling machine enters the intermediate tank after removing impurities through the silicon carbide ceramic membrane system, and then enters the reverse osmosis device. The water produced by the RO reverse osmosis membrane system enters the demineralized water production tank through the water production regulating valve. The production tank is equipped with on-line conductivity monitoring; when the conductivity of the demineralized water produced is qualified, the demineralized water produced is sent to the leveling water tank for use through the demineralized water production pump and the automatic valve.

10. The processing method according to claim 9, characterized in that: The operating temperature of the reverse osmosis membrane equipment is 5 - 40 °C; in step (4), when the conductivity exceeds the preset value, the system prompts an alarm, and the original demineralized water make-up water system is retained.

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