Organic membrane production wastewater treatment device

Abstract

The utility model relates to an organic membrane production wastewater treatment device which comprises a pretreatment unit, a front biochemical unit, a deep treatment unit and a rear biochemical unit, one end of the pretreatment unit is connected to membrane production wastewater, the other end of the pretreatment unit is connected with the front biochemical unit, and the deep treatment unit and the rear biochemical unit are sequentially connected behind the front biochemical unit. Heat exchangers are arranged between the pretreatment unit and the front biochemical unit and in the advanced treatment unit, the heat exchangers are one heat exchanger or two heat exchangers which are independently arranged and are used for cooling water, and the rear part of the rear biochemical unit is connected with an external water pipe for discharging. The device has the advantages of simple and reasonable structure, good treatment effect, high efficiency, stability, low cost and the like.

Description

Technical Field

[0001] This utility model belongs to the field of wastewater treatment technology, specifically relating to a wastewater treatment device for organic membrane production. Background Technology

[0002] With increasingly stringent wastewater discharge standards in my country, membrane separation technology is gradually replacing traditional water treatment technologies as the mainstay of wastewater treatment. However, the rapid development of the membrane industry also brings unique wastewater treatment challenges. A survey of a membrane manufacturing company revealed that its membrane production wastewater contains a large amount of non-degradable PVP (polyvinylpyrrolidone). PVP is a very common additive in the membrane manufacturing industry, possessing good hydrophilicity and widely used in PS / DMAC / DMF and PVDF / DMAC systems. PVP not only plays a crucial role in the pore formation of organic membranes but also significantly promotes slurry viscosity and post-membrane hydrophilicity. However, its poor degradation performance poses new challenges to wastewater treatment.

[0003] Currently, many manufacturers treat organic pollutants such as PVP by expanding wastewater treatment plant capacity or diluting their wastewater with tap water to meet discharge standards, which inadvertently increases their own costs and the burden on environmental treatment. Evaporation concentration is widely used due to its simplicity, but the process requires expensive specialized equipment, and its results are greatly affected by factors such as the type of solution, concentration factor, evaporation temperature, and actual operation, thus limiting its applicability. Chemical oxidation can reduce treatment costs and allows for adjustment of the oxidizing agent according to the solution properties; however, it requires the addition of large amounts of chemical reagents, causing severe pollution, which contradicts the concept of green production. Furthermore, this method relies on manual operation and is labor-intensive.

[0004] Therefore, an organic membrane production wastewater treatment device was designed to overcome the above problems. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide an organic membrane production wastewater treatment device with a simple and reasonable structure, good treatment effect, high efficiency and stability, and low cost.

[0006] This utility model is achieved through the following technical solution: an organic membrane production wastewater treatment device, comprising a pretreatment unit, a pre-biological treatment unit, a deep treatment unit, and a post-biological treatment unit. One end of the pretreatment unit is connected to the membrane production wastewater, and the other end is connected to the pre-biological treatment unit. The deep treatment unit and the post-biological treatment unit are sequentially connected after the pre-biological treatment unit. Heat exchangers are installed between the pretreatment unit and the pre-biological treatment unit, as well as within the deep treatment unit. The heat exchanger is either one heat exchanger or two independently installed heat exchangers, which cool the water. The post-biological treatment unit is connected to an external water pipe for discharge.

[0007] Preferably, the pretreatment unit is an equalization tank, which adjusts the pH value of the water. The tank is then connected to the first heat exchange pipe in the heat exchanger, and the first heat exchange pipe is connected to the pre-biochemical unit.

[0008] Preferably, the pre-biological unit consists of a first biological treatment tank, a second sedimentation tank, and an intermediate tank. The second sedimentation tank has two pipes at the bottom. One pipe is a return pipe that flows some sludge into the first biological treatment tank, and the other pipe is a sludge recovery pipe that is connected to the sludge return tank. The sludge is stored in the sludge return tank and then transported to the outside by a screw press. The intermediate tank is connected to the second heat exchange pipe of the heat exchanger at the rear. The second heat exchange pipe is connected to the deep treatment unit.

[0009] Preferably, the advanced treatment unit consists of a buffer tank, a reaction tank, a plate and frame structure, and a sedimentation tank, which are connected in sequence. The buffer tank is equipped with a dosing port, and the concentration of the reagent is added by detecting the water quality in the buffer tank. The bottom of the plate and frame structure and the sedimentation tank are provided with sludge pipes, which are connected to sludge recycling pipes to discharge sludge into a sludge tank for storage. The sedimentation tank is connected to the post-biological treatment tank at the rear.

[0010] Preferably, the post-biological treatment tank is a second biological treatment tank, which uses a three-stage A / O biological treatment device to further reduce the amount of COD, total nitrogen, and ammonia nitrogen to meet the emission standards.

[0011] Preferably, the agent is hydrogen peroxide, and the dosage of hydrogen peroxide is 10-20% of the COD value of the influent, with a reaction time of 15-30 minutes.

[0012] The beneficial effects of this utility model are as follows:

[0013] The organic membrane production wastewater treatment device designed in this utility model adopts a combined treatment process of "pre-biological treatment-deep treatment-post-biological treatment", which can achieve near-complete removal of recalcitrant organic matter PVP and reduce the chemical oxygen demand of membrane production wastewater by more than 95%. The membrane production wastewater treated by this process can meet the discharge requirements. The deep treatment unit only needs to add a small amount of chemical agent for the flocculation and precipitation of polyvinylpyrrolidone, and the agent consumption is low. The process uses online instruments to detect and adjust the process conditions in real time, and can be automated. Attached Figure Description

[0014] Figure 1 This is the overall process flow diagram of this utility model.

[0015] Figure 2 This is a schematic diagram of the process flow structure of this utility model.

[0016] Figure 3 The COD of the influent and effluent of each unit in Example 1 is given.

[0017] Figure 4 This is a sample image of the flocculent material filtered out from the catalytic polymerization unit in Example 1. Detailed Implementation

[0018] To enable those skilled in the art to more clearly understand the purpose, technical solution and advantages of this utility model, the present utility model will be further described below in conjunction with the accompanying drawings and embodiments.

[0019] In the description of this utility model, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", "horizontal", and "vertical" are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0020] The present invention will now be described in detail with reference to the accompanying drawings: Figure 1-2 As shown, an organic membrane production wastewater treatment device includes a pretreatment unit 1, a pre-biological treatment unit 2, a deep treatment unit 3, and a post-biological treatment unit 4. One end of the pretreatment unit 1 is connected to the membrane production wastewater 5, and the other end is connected to the pre-biological treatment unit 2. The deep treatment unit 3 and the post-biological treatment unit 4 are connected sequentially after the pre-biological treatment unit 2. Figure 2 As shown, heat exchangers 6 are installed between the pretreatment unit 1 and the pre-biochemical unit 2, as well as in the deep treatment unit 3. The heat exchanger 6 can be one or two independently installed heat exchangers to cool the water. The rear of the post-biochemical unit 4 is connected to an external water pipe for discharge.

[0021] The organic membrane production wastewater treatment device designed in this invention can effectively overcome the problems of high treatment cost, large reagent consumption, and poor treatment effect stability of existing technologies. It adopts a combined treatment process of "pre-biological treatment - deep treatment - post-biological treatment," which can achieve near-complete removal of recalcitrant organic pollutant PVP. The membrane wastewater treated by this process meets discharge requirements. The deep treatment unit only requires the addition of a small amount of chemical reagent for the flocculation and precipitation of polyvinylpyrrolidone, resulting in low reagent consumption. The pretreatment unit 1 is an equalization tank, which adjusts the pH value of the water. It is then connected to the first heat exchange pipe 7 in the heat exchanger 6, and the first heat exchange pipe 7 is connected to the pre-biological treatment unit 2.

[0022] The pre-biological unit 2 consists of a first biological treatment tank 8, a secondary sedimentation tank 9, and an intermediate tank 10. The secondary sedimentation tank 9 has two pipes at the bottom. One pipe is a return pipe 11, which flows some sludge into the first biological treatment tank 8. The other pipe is a sludge recovery pipe 12, which is connected to a sludge return tank 13 to store the sludge. The sludge is then transported to the outside by a screw press 14. The intermediate tank 10 is connected to the second heat exchange pipe 15 of the heat exchanger 6 at the rear. The second heat exchange pipe 15 is connected to the deep treatment unit.

[0023] The advanced treatment unit 3 consists of a buffer tank 16, a reaction tank 17, a plate and frame structure 18, and a sedimentation tank 19, which are connected sequentially. The buffer tank 16 is equipped with a dosing port 20, and the concentration of chemicals is adjusted by monitoring the water quality in the buffer tank. Both the plate and frame structure 18 and the sedimentation tank 19 have sludge pipes 21 at their bottoms, which connect to a sludge recovery pipe 12 to discharge sludge into a sludge tank 23 for storage. The sedimentation tank 19 is connected to a post-biological treatment tank 22. The post-biological treatment tank 22 is a second biological treatment tank, employing a three-stage A / O biological treatment system to further reduce COD, total nitrogen, and ammonia nitrogen levels to meet emission standards.

[0024] The organic membrane production wastewater treatment device designed in this utility model adopts a combined treatment process of "pre-biological treatment-deep treatment-post-biological treatment", which can achieve near-complete removal of recalcitrant organic matter PVP and reduce the chemical oxygen demand of membrane production wastewater by more than 95%. The membrane production wastewater treated by this process can meet the discharge requirements. The deep treatment unit only needs to add a small amount of chemical agent for the flocculation and precipitation of polyvinylpyrrolidone, and the agent consumption is low. The process uses online instruments to detect and adjust the process conditions in real time, and can be automated.

[0025] Example 1: This utility model uses membrane manufacturing wastewater from a domestic membrane manufacturing company for pilot-scale testing. The water quality indicators are as follows: water temperature 60~80℃, pH=4~7; COD 9000~21000 mg / L; conductivity <100μS / cm; suspended solids <20 mg / L; total nitrogen <1000 mg / L; ammonia nitrogen <10 mg / L.

[0026] Example 1

[0027] The membrane manufacturing wastewater is treated using a comprehensive deep treatment process comprising "pre-biological treatment - advanced treatment - post-biological treatment". The pre-biological treatment unit removes biodegradable organic matter from the wastewater using aerobic activated sludge, significantly reducing COD. The advanced treatment unit employs a specialized catalyst to catalyze the generation of free radicals from chemical agents, inducing intramolecular and intermolecular cross-linking reactions in PVP, resulting in flocculated flocs that can be separated from the aqueous phase through simple filtration. The post-biological treatment unit further reduces COD, total nitrogen, and ammonia nitrogen through a three-stage A / O biological treatment process to meet the company's emission standards.

[0028] The experimental setup is designed to process 1 m³ / h of water. The equalization tank serves to homogenize the water and adjust the pH of the incoming water. The heat exchanger uses the effluent from the pre-biological treatment unit to cool the high-temperature membrane-forming wastewater, meeting the influent requirements of the biological treatment tank. The buffer tank's main functions are water quality testing, process parameter control, and catalyst addition before the catalytic reaction. The plate and frame filter is used for the filtration and separation of PVP flocs. The pre-biological treatment unit is designed with a hydraulic retention time of 3-5 days, using activated sludge from the company's secondary sedimentation tank. The advanced treatment unit uses the company's self-developed homogeneous catalyst, with hydrogen peroxide added at a dosage of 10-20% of the influent COD value, and a reaction time of 15-30 minutes. The post-biological treatment unit uses the company's 3-stage A / O biological treatment experimental setup. After the experimental setup stabilized, it operated continuously for 7 days. The influent COD was 10000~12000 mg / L, and the effluent COD was <300 mg / L, ammonia nitrogen <30 mg / L, and total nitrogen <40 mg / L, meeting the company's discharge standards. The influent and effluent COD values ​​for each unit on day 7 are shown in the appendix. Figure 3 The deep processing unit filters out flocculent material (see attached image). Figure 4 .

[0029] The agent is hydrogen peroxide, and the dosage of hydrogen peroxide is 10-20% of the COD value of the influent, with a reaction time of 15-30 minutes.

[0030] The specific embodiments described herein are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. An organic film production wastewater treatment apparatus comprising a pretreatment unit, a pre-biochemical unit, a depth treatment unit, a post-biochemical unit, characterized in that: One end of the pretreatment unit is connected to membrane manufacturing wastewater, the other end is connected to the front biochemical unit, the front biochemical unit is connected to the deep treatment unit and the back biochemical unit in turn, heat exchangers are installed between the pretreatment unit and the front biochemical unit and in the deep treatment unit, the heat exchanger is one heat exchanger or two independent heat exchangers, the water temperature is cooled, and the back of the back biochemical unit is connected to the external water pipe for discharge.

2. The organic film production wastewater treatment device according to claim 1, characterized by: The pretreatment unit is a regulating tank, the PH value of the water is adjusted by the regulating tank, and the back is connected to the first heat exchange pipeline in the heat exchanger, and the first heat exchange pipeline is connected to the front biochemical unit.

3. The organic film production wastewater treatment device according to claim 2, characterized by: The front biochemical unit is composed of a first biochemical tank, a secondary sedimentation tank and an intermediate tank, two pipes are arranged in the bottom of the secondary sedimentation tank, one of the pipes is a reflux pipe, part of the sludge flows into the first biochemical tank, and the other pipe is a sludge recovery pipe, the sludge recovery pipe is connected to a sludge reflux tank, the sludge is stored in the sludge reflux tank, and is transported to the outside through a stacking screw machine, the back of the intermediate tank is connected to the second heat exchange pipeline of the heat exchanger, and the second heat exchange pipeline is connected to the deep treatment unit.

4. The organic film production wastewater treatment device according to claim 3, characterized by: The deep treatment unit is composed of a buffer tank, a reaction tank, a plate frame and a sedimentation tank, and is connected in turn, a dosing port is arranged in the buffer tank, the concentration of the medicament is added by detecting the water quality in the buffer tank, sludge pipes are arranged in the bottom of the plate frame and the sedimentation tank, the sludge pipes are connected to the sludge recovery pipe, and the sludge is discharged into the sludge tank for storage, and the back of the sedimentation tank is connected to the back biochemical tank.

5. The organic film production wastewater treatment device according to claim 4, characterized by: The back biochemical tank is a second biochemical tank, a three-stage A / O biochemical treatment equipment is used in the second biochemical tank, so that the amount of COD, total nitrogen and ammonia nitrogen is further reduced, and the discharge standard is reached.

6. The organic film production wastewater treatment device according to claim 5, characterized by: The medicament is hydrogen peroxide, the hydrogen peroxide dosage is 10-20% of the COD value of the inlet water, and the reaction time is 15-30 minutes.

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