Wastewater treatment system
By using an integrated reactor combining reverse osmosis and pervaporation membranes, the problems of low separation efficiency and high energy consumption of alcohol and ether wastewater in existing technologies have been solved, achieving efficient and low-energy wastewater treatment with high water production rate and simplified equipment.
Patent Information
- Application Number
- CN202423147584.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-19
- Publication Date
- 2026-02-03
- Estimated Expiration
- 2034-12-19
AI Technical Summary
Existing technologies are difficult to efficiently and with low energy consumption separate alcohol and ether wastewater in the concentration range of 1-10wt%, and the combined reverse osmosis and pervaporation process has problems such as large equipment footprint, high investment, and high energy consumption.
An integrated reactor employing a combination of reverse osmosis and pervaporation membranes achieves a continuous separation process by combining a reverse osmosis liquid tank, a reverse osmosis unit, a buffer tank, a pervaporation unit, and a three-way valve, and using an alcohol content refractometer to control the flow direction, thus simplifying the equipment system.
It achieves efficient, continuous, and low-energy-consumption separation of alcohol and ether wastewater, with a water production rate of over 90%, and the pervaporation liquid concentration can reach 30wt% for reuse. The equipment configuration is simplified, and the treatment concentration range is greatly improved.
Smart Images
Figure CN223866412U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a wastewater treatment system. Background Technology
[0002] With the widespread use of water-soluble solvents in manufacturing processes such as parts cleaning and pipeline cleaning, a large amount of high-concentration organic wastewater, referred to as water-based waste solvent, is generated. Due to its high concentration, this type of wastewater is treated as hazardous waste and incinerated externally. In fact, this type of wastewater is more than 90 wt% water. After removing resin substances, the remaining organic matter mainly consists of alcohols and ethers, which have recycling value.
[0003] After pretreatment, the aqueous waste solvent contains 1-10 wt% alcohol and ether organic matter. Researchers have used ultrafiltration (UF) and reverse osmosis (RO) to separate and purify this waste solvent. However, since the pore size of ultrafiltration membrane materials is generally less than 0.1 μm, and the organic matter in the wastewater is soluble in water, the organic matter removal rate is less than 10%, which cannot effectively separate the solvent and water. Reverse osmosis membranes, with their excellent throttling performance, can achieve an organic matter retention rate of up to 90%, but the ratio of permeate to concentrate is 1:1, resulting in a concentrate concentration of less than 15 wt%, which cannot meet the requirements for secondary utilization.
[0004] For the aforementioned 1-10 wt% alcohol ether organic matter-water system, the concentration can be effectively reduced to 0.5 wt% by directly using pervaporation membranes (PV) made of materials such as polydimethylsiloxane (PDMS) and mixed matrix membranes. However, the investment cost is high, and the quality of the produced water cannot meet the environmental discharge standards, requiring the use of traditional wastewater treatment processes.
[0005] In the field of wastewater treatment, especially for alcohol and ether wastewater with a concentration range of 1-10 wt%, the following difficulties exist when using only pervaporation membrane technology or reverse osmosis membrane technology: 1) Completely separating organic matter from wastewater to meet discharge standards such as GB 8978 requires high separation factor of the membrane material if pervaporation membrane is used; 2) For alcohol and ether system wastewater with a concentration above 10 wt%, the flux of reverse osmosis membrane is low. Even under high pressure, the amount of concentrate produced is still higher than 40%, resulting in low emission reduction efficiency. Based on the above problems, a combined reverse osmosis and pervaporation process was developed to achieve high-purity separation of organic matter and water. That is, after separating a 10 wt% alcohol and ether system with water, a 50 wt% concentrate is obtained, and the organic content of the product water is less than 0.1 wt%.
[0006] Combining reverse osmosis membranes and pervaporation-to-organic membranes presents the following technical challenges: 1) The pervaporation-to-organic membrane reaction typically requires temperatures between 50-70°C, while traditional reverse osmosis membrane materials can only withstand temperatures up to 45°C. Above this temperature, the mechanical properties and appearance of the membrane material will change, affecting performance. Therefore, combining the two requires a cooling and then heating process, resulting in high energy consumption; 2) The flux of reverse osmosis membranes is typically 5-10 L / m³. 2 The pervaporation membrane flux is only 1-2 L / m³, while the pervaporation membrane flux is over 1 h. 2 Different organic concentrations result in different fluxes, often requiring batch reactors, which leads to problems such as large equipment footprint and high investment. Utility Model Content
[0007] The technical problem this invention aims to solve is to overcome the shortcomings of existing technologies and provide a wastewater treatment system. For alcohol-ether-water systems with concentrations of 1-10 wt%, an integrated reactor combining reverse osmosis and pervaporation membranes is employed to achieve a highly efficient, continuous, and low-energy-consumption separation method, simplifying the equipment system composition.
[0008] The present invention solves the above-mentioned technical problems through the following technical solution:
[0009] This utility model provides a wastewater treatment system, which includes a reverse osmosis liquid tank, a reverse osmosis device, a buffer tank, a pervaporation device, and a three-way valve; the buffer tank is equipped with an alcohol content refractometer, and the alcohol content refractometer is signal-connected to the three-way valve;
[0010] The reverse osmosis liquid tank is equipped with a first wastewater inlet, a pervaporation product water inlet, and a reverse osmosis liquid outlet; the buffer tank is equipped with a second wastewater inlet, a reverse osmosis concentrate inlet, and a pervaporation liquid outlet; the three-way valve is equipped with a first outlet, a second outlet, and an inlet;
[0011] The reverse osmosis unit is provided with a reverse osmosis feed inlet, a reverse osmosis permeate outlet, and a reverse osmosis concentrate outlet; the pervaporation unit is provided with a pervaporation feed inlet, a pervaporation permeate outlet, and a pervaporation permeate outlet.
[0012] The first wastewater inlet and the first outlet are connected by a first wastewater pipeline; the pervaporation product water inlet and the pervaporation product water outlet are connected by a pervaporation product water pipeline; the reverse osmosis liquid outlet is connected to the reverse osmosis inlet.
[0013] The second wastewater inlet and the second outlet are connected by a second wastewater pipeline; the reverse osmosis concentrate inlet and the reverse osmosis concentrate outlet are connected by a reverse osmosis concentrate pipeline; and the pervaporated liquid outlet is connected to the pervaporation inlet.
[0014] In this invention, the reverse osmosis liquid tank can collect wastewater generated during pretreatment, such as thermal water produced by vacuum distillation, multi-effect evaporators, etc.
[0015] In this invention, instruments such as a level gauge, pH meter, conductivity meter, and thermometer can be added to the reverse osmosis liquid tank to monitor the current water quality.
[0016] In this invention, a reverse osmosis liquid booster pump is provided between the reverse osmosis liquid outlet and the reverse osmosis liquid inlet. The reverse osmosis liquid outlet and the inlet of the reverse osmosis liquid booster pump are connected through a first pipeline, and the outlet of the reverse osmosis liquid booster pump and the reverse osmosis liquid inlet are connected through a second pipeline.
[0017] The first pipeline is provided with node A, the reverse osmosis concentrate pipeline is provided with node B, and a reverse osmosis return pipeline is provided between node A and node B.
[0018] The reverse osmosis fluid booster pump can be a multi-stage high-pressure pump or a combination of high-pressure pumps.
[0019] In this invention, conventionally, the reverse osmosis device is equipped with a reverse osmosis membrane assembly. The membrane material of the reverse osmosis membrane assembly can be polyimide or cellulose acetate, used to intercept small molecule organic matter.
[0020] In this invention, conventionally, the reverse osmosis permeate outlet is connected to the reverse osmosis permeate tank via a reverse osmosis permeate pipeline.
[0021] In this invention, the buffer water tank may be equipped with a heating component, such as a heating coil.
[0022] In this invention, the buffer tank should not be too large in volume, and should be designed to meet the heating requirements of a single pervaporation device.
[0023] In this invention, the alcohol content refractometer can detect the alcohol content in the buffer tank using the principle of refractive index. If the alcohol content is ≥5%, the three-way valve switches to allow wastewater to enter the buffer tank first; if the alcohol content is <5%, the three-way valve switches to allow wastewater to enter the reverse osmosis solution tank first. Alcohol content refers to the equivalent mass concentration of ethanol in a liquid, expressed in % (w / w).
[0024] In this invention, a pervaporation liquid booster pump is provided between the pervaporation liquid outlet and the pervaporation liquid inlet. The pervaporation liquid outlet and the inlet of the pervaporation liquid booster pump are connected through a third pipeline, and the outlet of the pervaporation liquid booster pump and the pervaporation liquid inlet are connected through a fourth pipeline.
[0025] The third pipeline is provided with node C, the pervaporation product water pipeline is provided with node D, and a pervaporation product water return pipeline is provided between node C and node D.
[0026] The pervaporation liquid booster pump can be a multi-stage high-pressure pump or a combination of high-pressure pumps.
[0027] In this invention, conventionally, the pervaporation device is provided with a pervaporation membrane assembly, which can be a non-open vacuum flat sheet membrane assembly, a tubular membrane assembly, or a spiral wound membrane assembly.
[0028] In this invention, conventionally, the pervaporation permeate outlet is connected to the pervaporation concentrate tank via a pervaporation permeate pipeline.
[0029] The pervaporation permeate pipeline and the reverse osmosis concentrate pipeline can exchange heat in a heat exchanger.
[0030] The positive and progressive effects of this utility model are as follows:
[0031] (1) In this utility model, by using a combination of reverse osmosis membrane and pervaporation membrane, the high concentration alcohol ether wastewater can be effectively separated with a water production rate of over 90%, and the water quality can meet the Class III discharge standard. The pervaporation liquid concentration is over 30wt% and can be reused.
[0032] (2) This utility model is a continuous reaction process, which greatly simplifies the system equipment configuration and energy consumption;
[0033] (3) In this utility model, organic matter and water can be separated for 1-10wt% aqueous solvents. When the alcohol content in the buffer tank is ≥5%, pervaporation membrane separation can be performed first, and the pervaporation membrane product water can be separated by reverse osmosis membrane separation. When the alcohol content in the buffer tank is <5%, reverse osmosis membrane separation can be performed first, and the reverse osmosis membrane concentrate water can be separated by pervaporation membrane separation. Compared with the single membrane method, the treatment concentration range is greatly improved. Attached Figure Description
[0034] Figure 1 This is a schematic diagram of the wastewater treatment system in Example 1;
[0035] The following are the labels in the diagram: First wastewater pipeline 001, Second wastewater pipeline 01, Reverse osmosis return pipeline 02, Reverse osmosis concentrate pipeline 03, Reverse osmosis permeate pipeline 04, Pervaporation permeate pipeline 05, Pervaporation permeate return pipeline 06, Pervaporation permeate pipeline 07, Reverse osmosis liquid tank 11, Buffer tank 12, Reverse osmosis permeate tank 13, Pervaporation concentrate tank 14, Reverse osmosis liquid booster pump 21, Pervaporation liquid booster pump 22, Reverse osmosis unit 31, Pervaporation unit 41, Three-way valve 101, Alcohol content refractometer 103. Detailed Implementation
[0036] The present invention will be described more clearly and completely below with reference to the accompanying drawings, using a preferred embodiment.
[0037] Example 1
[0038] A wastewater treatment system, such as Figure 1 It includes a reverse osmosis liquid tank 11, a reverse osmosis unit 31, a buffer tank 12, a pervaporation unit 41, and a three-way valve 101; the buffer tank 12 is equipped with an alcohol content refractometer 103, which is connected to the three-way valve 101.
[0039] The reverse osmosis liquid tank 11 is equipped with a first wastewater inlet, a pervaporation product water inlet, and a reverse osmosis liquid outlet; the buffer tank 12 is equipped with a second wastewater inlet, a reverse osmosis concentrate inlet, and a pervaporation liquid outlet; the three-way valve 101 is equipped with a first outlet, a second outlet, and an inlet; the reverse osmosis unit 31 is equipped with a reverse osmosis inlet, a reverse osmosis product water outlet, and a reverse osmosis concentrate outlet; the pervaporation unit 41 is equipped with a pervaporation inlet, a pervaporation product water outlet, and a pervaporation permeate outlet.
[0040] The first wastewater inlet and the first outlet are connected by the first wastewater pipeline 001; the pervaporation product water inlet and the pervaporation product water outlet are connected by the pervaporation product water pipeline 07; the reverse osmosis liquid outlet is connected to the reverse osmosis inlet; the second wastewater inlet and the second outlet are connected by the second wastewater pipeline 01; the reverse osmosis concentrate inlet and the reverse osmosis concentrate outlet are connected by the reverse osmosis concentrate pipeline 03; and the pervaporation liquid outlet is connected to the pervaporation inlet.
[0041] In this embodiment, a reverse osmosis liquid booster pump 21 is installed between the reverse osmosis liquid outlet and the reverse osmosis liquid inlet. The reverse osmosis liquid outlet and the inlet of the reverse osmosis liquid booster pump 21 are connected through a first pipeline, and the outlet of the reverse osmosis liquid booster pump 21 is connected to the reverse osmosis liquid inlet through a second pipeline. A node A is provided on the first pipeline, a node B is provided on the reverse osmosis concentrate pipeline 03, and a reverse osmosis return pipeline 02 is provided between node A and node B. The reverse osmosis liquid booster pump 21 is a combined high-pressure pump, which brings the reverse osmosis liquid pressure to any value between 20-50 bar, allowing it to enter from the reverse osmosis liquid inlet.
[0042] In this embodiment, the reverse osmosis unit 31 is equipped with a reverse osmosis membrane module, and the membrane material of the reverse osmosis membrane module is polyimide. In other embodiments, the membrane material may be cellulose acetate. The reverse osmosis permeate outlet is connected to the reverse osmosis permeate tank 13 through the reverse osmosis permeate pipeline 04. In this embodiment, the operating temperature of the reverse osmosis unit 31 is any value between 50-70℃, and the flux of the reverse osmosis membrane module is generally 3-10 L / m³. 2In this embodiment, the organic matter removal rate of reverse osmosis can reach 95%. In other embodiments, a two-stage reverse osmosis unit 31 can be set to achieve a COD emission standard of less than 500 mg / L for the produced water.
[0043] In this embodiment, a heating coil is installed inside the buffer tank 12 to control the water temperature inside the buffer tank 12 to any value between 60-70℃. The alcohol content refractometer 103 can detect the alcohol content inside the buffer tank 12. If the alcohol content is high, the three-way valve 101 switches to allow wastewater to enter the buffer tank 12 first. If the alcohol content is low, the three-way valve 101 switches to allow wastewater to enter the reverse osmosis liquid tank 11 first.
[0044] In this embodiment, a pervaporation liquid booster pump 22 is provided between the pervaporation liquid outlet and the pervaporation liquid inlet. The pervaporation liquid outlet and the inlet of the pervaporation liquid booster pump 22 are connected through a third pipeline, and the outlet of the pervaporation liquid booster pump 22 and the pervaporation liquid inlet are connected through a fourth pipeline. A node C is provided on the third pipeline, a node D is provided on the pervaporation product water pipeline 07, and a pervaporation product water return pipeline 06 is provided between node C and node D.
[0045] In this embodiment, the pervaporation device 41 is equipped with a pervaporation membrane module, which is a non-open vacuum flat sheet membrane module. In other embodiments, the pervaporation membrane module is a tubular membrane module or a spiral wound membrane module. In this embodiment, the flow velocity entering the pervaporation membrane module is any value not less than 2 m / min, and the absolute pressure on the vacuum side is any value not more than 2 kPa.
[0046] In this embodiment, the pervaporation permeate outlet is connected to the pervaporation concentrate tank 14 via the pervaporation permeate pipeline 05. The pervaporation permeate pipeline 05 and the reverse osmosis concentrate pipeline 03 exchange heat in a heat exchanger. The pervaporation permeate in the pervaporation permeate pipeline 05 first exchanges heat with the reverse osmosis concentrate in the reverse osmosis concentrate pipeline 03 in the heat exchanger, and then passes through a low-temperature heat exchanger. The temperature of the low-temperature heat exchanger is set to any value between -5 and -10°C. The condensed pervaporation permeate enters the pervaporation concentrate tank 14. The pervaporation permeate in the pervaporation permeate pipeline 07 flows back to the reverse osmosis liquid tank 11. The temperature of the pervaporation permeate is any value between 50 and 60°C, which can exchange heat with the reverse osmosis concentrate in the reverse osmosis concentrate pipeline 03 to lower the temperature of the pervaporation permeate to room temperature.
[0047] In this embodiment, the inlet flow rate of either the first wastewater pipeline 001 or the second wastewater pipeline 01 should be the sum of the flow rates of the reverse osmosis permeate pipeline 04 and the pervaporation liquid pipeline 05. In a more preferred embodiment, the ratio of the flow rates of the reverse osmosis permeate pipeline 04 and the pervaporation liquid pipeline 05 is typically any value of (10-20):1, and the appropriate scale can be designed by calculation based on the actual required treatment volume. In this embodiment, the permeate production rate is generally 90%-95%, and the organic matter concentration of the pervaporation liquid is higher than 30wt%, so secondary cleaning of the reuse line can be considered.
[0048] Operating Condition 1: Low-Concentration Wastewater Treatment
[0049] A domestic automobile manufacturing plant's painting process line produces 660 m³ of water-based wastewater. 3 / a, a solution mainly composed of alcohol ethers (such as ethylene glycol butyl ether and diethylene glycol butyl ether), after pretreatment coagulation, pressure filtration and low-temperature evaporation, produces water with a CODcr of 45,000 mg / L, equivalent to 2wt% ethylene glycol butyl ether. This water cannot be recycled or directly discharged to the wastewater treatment plant and requires further treatment to minimize the environmental impact of industrial wastewater discharge.
[0050] Under this operating condition, the alcohol content of the liquid in buffer tank 12 is 3%, and the wastewater flows into reverse osmosis liquid tank 11 through the first wastewater pipeline 001 at a flow rate of 160 L / h. The specific parameters of the relevant equipment and processes are disclosed as follows:
[0051] The effective volume of the reverse osmosis solution tank 11 is 400 L. The reverse osmosis solution booster pump 21 consists of one 200 L / h high-pressure pump and one 2 m... 3 The system consists of a high-pressure pump connected in series, with a head of 20-30 bar. The reverse osmosis membrane module consists of two 8-inch membranes connected in series. The feed flow rate of the reverse osmosis unit 31 is 200 L / h via the reverse osmosis membrane + 2 m 3 / h through the outer casing, feed temperature 40℃, feed pressure 20 bar, reverse osmosis permeate pipeline 04 permeate flow rate 150 L / h, total reverse osmosis concentrate flow rate 50 L / h, 2 m 3 The material passing through the shell flows back to the reverse osmosis liquid booster pump 21 via the reverse osmosis return pipeline 02, while another part of the reverse osmosis concentrate flows into the buffer tank 12 via the reverse osmosis concentrate pipeline 03, with a flow rate of 50 L / h.
[0052] The effective volume of the buffer tank 12 is 100 L. The flow rate of the pervaporation liquid booster pump 22 is 300 L / h. Two 15 m³ pervaporation membrane modules are selected in series. 2The membrane module is a flat-sheet pervaporation membrane. The feed flow rate of the pervaporation unit 41 is 300 L / h, the feed temperature is 60℃, the feed pressure is 1 bar, the permeate flow rate of the pervaporation permeate line 05 is 10 L / h, and the total flow rate of the pervaporation permeate of the pervaporation unit 41 is 290 L / h. 250 L / h of the permeate is returned to the pervaporation liquid booster pump 22 via the pervaporation permeate return line 06, and the other part of the pervaporation permeate is returned to the reverse osmosis liquid tank 11 via the pervaporation permeate line 07. The flow rate of the pervaporation permeate line 07 is 40 L / h.
[0053] The effective volume of the reverse osmosis permeate tank 13 is 2 m³. 3 The CODcr of the permeate is 3500 mg / L. After reaching the high liquid level, it automatically flows to the factory's electrophoresis wastewater pipe. The effective volume of the pervaporation concentrate tank 14 is 200 L. After the collected liquid reaches the high liquid level, the machine is stopped and the vacuum is broken to discharge it to the collection point. The organic matter concentration of the collected pervaporation liquid is 31 wt%, which can be reused as a cleaning agent, thereby realizing the reduction and resource utilization of waste solvents and reducing pollution and carbon emissions for customers.
[0054] Operating Condition 2: High Alcohol Content Wastewater Treatment
[0055] A domestic automobile manufacturing plant's painting process line produces 1200 m³ of water-based wastewater. 3 / a, a solution mainly composed of alcohol ethers (such as ethylene glycol butyl ether and diethylene glycol butyl ether), after pretreatment coagulation, pressure filtration and low-temperature evaporation, produces a CODcr of 110,000 mg / L, equivalent to a 5wt% ethylene glycol butyl ether concentration. It cannot be recycled or directly discharged to the sewage treatment plant and requires further treatment to minimize the environmental impact of industrial wastewater discharge.
[0056] Under this operating condition, the alcohol content of the liquid in buffer tank 12 is 6%, and the wastewater flows into buffer tank 12 through the second wastewater pipeline 01 at a flow rate of 40 L / h. The specific parameters of the relevant equipment and processes are disclosed as follows:
[0057] The effective volume of the buffer tank 12 is 400 L. The flow rate of the pervaporation liquid booster pump 22 is 300 L / h. The pervaporation membrane module consists of six 15 m³ membranes connected in series. 2 The membrane module is a flat-plate pervaporation membrane. The feed flow rate of the pervaporation unit 41 is 10 L / h, the feed temperature is 60℃, the feed pressure is 1 bar, the permeate flow rate of the pervaporation permeate line 05 is 10 L / h, and the total flow rate of the pervaporation permeate of the pervaporation unit 41 is 290 L / h. 250 L / h of the permeate is returned to the pervaporation liquid booster pump 22 via the pervaporation permeate return line 06, and the other part of the pervaporation permeate is returned to the reverse osmosis liquid tank 11 via the pervaporation permeate line 07. The flow rate of the pervaporation permeate line 07 is 40 L / h.
[0058] The effective volume of the reverse osmosis solution tank 11 is 400 L. The reverse osmosis solution booster pump 21 consists of one 40 L / h high-pressure pump and one 2 m... 3 The system consists of a high-pressure pump connected in series, with a head of 20-30 bar. The reverse osmosis membrane module consists of two 8-inch membranes connected in series. The feed flow rate of the reverse osmosis unit 31 is 40 L / h via the reverse osmosis membrane + 2 m 3 / h through the outer casing, feed temperature 40℃, feed pressure 20 bar, reverse osmosis permeate flow rate 30 L / h, total reverse osmosis concentrate flow rate 10 L / h, 2 m 3 The material passing through the shell flows back to the reverse osmosis liquid booster pump 21 via the reverse osmosis return pipeline 02, while another part of the reverse osmosis concentrate flows into the buffer tank 12 via the reverse osmosis concentrate pipeline 03, with a flow rate of 10 L / h.
[0059] The effective volume of the reverse osmosis permeate tank 13 is 4 m³. 3 The CODcr of the produced water is 2600 mg / L. After reaching the high liquid level, it automatically flows to the factory's electrophoresis wastewater pipe. The effective volume of the pervaporation concentrate tank 14 is 1000 L. After the collected liquid reaches the high liquid level, the machine is stopped and the vacuum is broken to discharge it to the collection point. The organic matter concentration of the collected pervaporation liquid is 32wt%, which can be reused as a cleaning agent, thereby realizing the reduction and resource utilization of waste solvents and reducing pollution and carbon emissions for customers.
Claims
1. A wastewater treatment system, characterized in that, It includes a reverse osmosis liquid tank (11), a reverse osmosis device (31), a buffer tank (12), a pervaporation device (41), and a three-way valve (101); the buffer tank (12) is equipped with an alcohol content refractometer (103), and the alcohol content refractometer (103) is connected to the three-way valve (101) by signal. The reverse osmosis liquid tank (11) is provided with a first wastewater inlet, a pervaporation product water inlet, and a reverse osmosis liquid outlet; the buffer tank (12) is provided with a second wastewater inlet, a reverse osmosis concentrate inlet, and a pervaporation liquid outlet; the three-way valve (101) is provided with a first outlet, a second outlet, and an inlet; The reverse osmosis device (31) is provided with a reverse osmosis feed inlet, a reverse osmosis permeate outlet and a reverse osmosis concentrate outlet; the pervaporation device (41) is provided with a pervaporation feed inlet, a pervaporation permeate outlet and a pervaporation permeate outlet; The first wastewater inlet and the first outlet are connected by a first wastewater pipeline (001); the pervaporation product water inlet and the pervaporation product water outlet are connected by a pervaporation product water pipeline (07); the reverse osmosis liquid outlet is connected to the reverse osmosis inlet; The second wastewater inlet and the second outlet are connected by a second wastewater pipeline (01); the reverse osmosis concentrate inlet and the reverse osmosis concentrate outlet are connected by a reverse osmosis concentrate pipeline (03); and the pervaporated liquid outlet is connected to the pervaporation inlet.
2. The wastewater treatment system as described in claim 1, characterized in that, A reverse osmosis liquid booster pump (21) is provided between the reverse osmosis liquid outlet and the reverse osmosis liquid inlet. The reverse osmosis liquid outlet and the inlet of the reverse osmosis liquid booster pump (21) are connected through a first pipeline, and the outlet of the reverse osmosis liquid booster pump (21) and the reverse osmosis liquid inlet are connected through a second pipeline.
3. The wastewater treatment system as described in claim 2, characterized in that, The first pipeline is provided with node A, the reverse osmosis concentrate pipeline (03) is provided with node B, and a reverse osmosis return pipeline (02) is provided between node A and node B. The reverse osmosis liquid booster pump (21) is a multi-stage high-pressure pump or a combination high-pressure pump.
4. The wastewater treatment system as described in claim 1, characterized in that, The reverse osmosis device (31) is equipped with a reverse osmosis membrane assembly, the membrane material of which is polyimide or cellulose acetate; The reverse osmosis permeate outlet is connected to the reverse osmosis permeate tank (13) via a reverse osmosis permeate pipeline (04).
5. The wastewater treatment system as described in claim 1, characterized in that, The buffer water tank (12) is equipped with a heating component.
6. The wastewater treatment system as described in claim 1, characterized in that, A pervaporation liquid booster pump (22) is provided between the pervaporation liquid outlet and the pervaporation liquid inlet. The pervaporation liquid outlet is connected to the inlet of the pervaporation liquid booster pump (22) through a third pipeline, and the outlet of the pervaporation liquid booster pump (22) is connected to the pervaporation liquid inlet through a fourth pipeline.
7. The wastewater treatment system as described in claim 6, characterized in that, The third pipeline is provided with node C, the pervaporation water production pipeline (07) is provided with node D, and a pervaporation water production return pipeline (06) is provided between node C and node D. The pervaporation liquid booster pump (22) is a multi-stage high-pressure pump or a combination high-pressure pump.
8. The wastewater treatment system as described in claim 1, characterized in that, The pervaporation device (41) is equipped with a pervaporation membrane assembly, which is a non-open vacuum flat sheet membrane assembly, a tubular membrane assembly, or a spiral wound membrane assembly.
9. The wastewater treatment system as described in claim 1, characterized in that, The pervaporation permeate outlet is connected to the pervaporation concentrate tank (14) via the pervaporation permeate pipeline (05).
10. The wastewater treatment system as described in claim 9, characterized in that, The pervaporation permeate line (05) and the reverse osmosis concentrate line (03) exchange heat in a heat exchanger.