Acid-resistant nanofiltration and reverse osmosis membrane filtering device

Abstract

The utility model discloses an acid-resistant nanofiltration and reverse osmosis membrane filtering device, and belongs to the technical field of wastewater treatment. The device comprises a stock solution tank, a first circulating pump, a filter, a second circulating pump, a filter membrane, a heat exchanger, a clear liquid recovery tank, a concentrated liquid recovery tank and a control cabinet, the stock solution tank is connected with the first circulating pump, the first circulating pump is connected with the filter, the filter is connected with the second circulating pump, and the second circulating pump is connected with the concentrated liquid recovery tank. The second circulating pump is connected with the filtering membrane; the lower part of the side surface of the filtering membrane is connected with the top end of the heat exchanger through a pipeline; a clear liquid recovery pipe and a concentrated liquid recovery pipe are respectively arranged at the bottoms of the filter membrane and the heat exchanger; the clear liquid recovery tank is positioned right below the clear liquid recovery pipe, and the concentrated liquid recovery tank is positioned right below the concentrated liquid recovery pipe; the filtering device provided by the utility model is stable in operation effect, small in occupied area and low in manufacturing cost.

Description

Technical Field

[0001] The utility model relates to the technical field of wastewater treatment, in particular to an acid-resistant nanofiltration and reverse osmosis membrane filtering device. Background Art

[0002] Nowadays, with the rapid development of the chemical industry, metal processing industry, electroplating industry and other industries, a large amount of acidic wastewater will be generated in the process of acid production and acid use. Common acidic wastewaters include hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, etc. Such acidic wastewater is highly corrosive and highly polluting to the environment. If not properly handled, once it enters the natural water body, it will cause great harm to the environment and human life. Therefore, such wastewater needs to be treated in time.

[0003] At present, the existing traditional treatment methods for this type of acidic wastewater include: chemical precipitation method, neutralization method, micro-electrolysis technology, oxidation-reduction method, etc. However, the traditional treatment methods have defects such as large footprint, high operating costs, and unstable treatment effects. Therefore, new treatment methods have also emerged. Among them, membrane treatment has a good market prospect and technical advantages in treating acidic wastewater. Membrane treatment technology includes nanofiltration, reverse osmosis and other methods. Among them, reverse osmosis is an ultra-high precision membrane separation technology that uses pressure difference. It can filter out most impurities in the water and only allow water molecules to pass through; the filtration accuracy of nanofiltration is between ultrafiltration and reverse osmosis, and the desalination rate is lower than that of reverse osmosis. It can pass water molecules and most inorganic acids. The membrane treatment device has the advantages of low cost, small footprint, and stable operation. At the same time, the membrane treatment device is easy to operate and has little occupational hazard to operators. It is a method for treating acidic wastewater that can be vigorously promoted. Summary of the invention

[0004] Therefore, it is necessary to provide a membrane treatment device which can effectively treat acidic wastewater and has a small footprint, stable operation and low cost.

[0005] To achieve the above-mentioned purpose, the inventor provides an acid-resistant nanofiltration and reverse osmosis membrane filtration device, including a raw liquid tank, a first circulation pump, a filter, a second circulation pump, a filter membrane, a heat exchanger, a clear liquid recovery tank, a concentrated liquid recovery tank and a control cabinet, wherein the raw liquid tank is connected to the first circulation pump through a liquid outlet pipe, a connecting pipe and a first liquid inlet pipe in sequence, the first circulation pump is connected to the filter through a second liquid inlet pipe, the filter is connected to the second circulation pump through a third liquid inlet pipe, and the second circulation pump is connected to the fourth liquid inlet pipe. The filter membrane is connected, and the lower side of the filter membrane is connected to the top of the heat exchanger through a pipeline; the filter membrane and the bottom of the heat exchanger are respectively provided with a clear liquid recovery pipe and a concentrated liquid recovery pipe, the clear liquid recovery pipe is provided with a clear liquid outlet pipe, and the concentrated liquid recovery pipe is provided with a concentrated liquid outlet pipe; the clear liquid recovery tank is located directly below the clear liquid recovery pipe, and the concentrated liquid recovery tank is located directly below the concentrated liquid recovery pipe; valves are provided on the liquid outlet pipe, the clear liquid recovery pipe, the concentrated liquid recovery pipe, the clear liquid outlet pipe, and the concentrated liquid outlet pipe.

[0006] Furthermore, the filtration membrane is an acid-resistant nanofiltration membrane or an acid-resistant reverse osmosis membrane.

[0007] Furthermore, energy accumulators are provided on both the second liquid inlet pipe and the fourth liquid inlet pipe.

[0008] Furthermore, a cleaning pipe whose circulation is controlled by a valve is provided at the connection between the connecting pipe and the first liquid inlet pipe.

[0009] Furthermore, a protective cover is provided above the filter membrane.

[0010] Furthermore, the connecting tube is a polyfluoro tube.

[0011] Furthermore, a respirator is provided on the top of the raw liquid tank.

[0012] Furthermore, the first circulation pump, the filter, the second circulation pump, the filter membrane, the heat exchanger, the clear liquid recovery tank, the concentrated liquid recovery pipe and the control cabinet are all arranged on a frame, and a roller is arranged at the bottom of the frame.

[0013] Furthermore, a bypass pipe whose flow is controlled by a valve is arranged in parallel on the third liquid inlet pipe and the fourth liquid inlet pipe.

[0014] Furthermore, the first circulation pump and the second circulation pump are both acid-resistant diaphragm pumps.

[0015] Different from the prior art, the above technical solution has the following beneficial effects:

[0016] The utility model utilizes a stock liquid tank to store acidic waste liquid, and utilizes a first circulating pump and a second circulating pump to transport the acidic waste liquid in the stock liquid tank to a filter, a filter membrane and a heat exchanger, and filters waste water of different pH values ​​through different materials. While having acid resistance, the utility model can effectively filter and recycle the acidic waste liquid, and effectively remove impurities and harmful substances in the acidic waste liquid. Moreover, the waste water is driven into the filter and the filter membrane for filtration through the circulating pump during the entire treatment process, and the operation is stable. Secondly, the entire filtering device can be integrated on a frame, and there is no need to build an overly large reaction pool, so the footprint is small, the applicability is strong, and the cost is relatively low. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a three-dimensional schematic diagram of the filtering device described in a specific embodiment;

[0018] Figure 2 It is a three-dimensional schematic diagram of the filtering device described in the specific embodiment from another perspective;

[0019] Figure 3 It is a front view schematic diagram of the filtering device described in the specific implementation mode;

[0020] Figure 4 It is a schematic side view of the filtering device described in a specific implementation manner.

[0021] Description of reference numerals:

[0022] 1. Raw liquid tank, 2. First circulation pump, 3. Filter, 4. Second circulation pump, 5. Filter membrane, 6. Heat exchanger, 7. Clear liquid recovery tank, 8. Concentrated liquid recovery tank, 9. Control cabinet, 10. Liquid outlet pipe, 11. Connecting pipe, 12. First liquid inlet pipe, 13. Second liquid inlet pipe, 14. Third liquid inlet pipe, 15. Fourth liquid inlet pipe, 16. Clear liquid recovery pipe, 17. Concentrated liquid recovery pipe, 18. Clear liquid outlet pipe, 19. Concentrated liquid outlet pipe, 20. Respirator, 21. Energy storage device, 22. Cleaning pipe, 23. Bypass pipe, 24. Protective cover, 25. Rack, 26. Roller. DETAILED DESCRIPTION

[0023] In order to explain the technical content, structural features, achieved objectives and effects of the technical solution in detail, the following is a detailed description in conjunction with specific embodiments and accompanying drawings.

[0024] Please also read Figures 1 to 4As shown in the figure, this embodiment provides an acid-resistant nanofiltration reverse osmosis membrane filtration device, including a raw liquid tank 1, a first circulation pump 2, a filter 3, a second circulation pump 4, a filter membrane 5, a heat exchanger 6, a clear liquid recovery tank 7, a concentrated liquid recovery tank 8 and a control cabinet 9. The raw liquid tank 1 is connected to the first circulation pump 2 through a liquid outlet pipe 10, a connecting pipe 11 and a first liquid inlet pipe 12 in sequence, wherein the liquid outlet pipe 10 is fixedly connected to the bottom of the raw liquid tank 1, one end of the connecting pipe 11 is fixedly connected to the liquid outlet pipe 10, and the other end is detachably connected to the first liquid inlet pipe 12 through a high-pressure clamp, and the first liquid inlet pipe 12 is installed on the first circulation pump 2; the first circulation pump 2 is connected to the filter through the second liquid inlet pipe 13 3, the bottom of the filter 3 is connected to the second circulation pump 4 through the third liquid inlet pipe 14, the second circulation pump 4 is connected to the lateral upper end of the filter membrane 5 through the fourth liquid inlet pipe 15, and the lateral bottom end of the filter membrane 5 is connected to the top of the heat exchanger 6 through a pipeline; a clear liquid recovery pipe 16 and a concentrated liquid recovery pipe 17 are respectively provided at the bottom of the filter membrane 6 and the heat exchanger 6, a clear liquid recovery pipe 18 is provided on the clear liquid recovery pipe 16, and a concentrated liquid outlet pipe 19 is provided on the concentrated liquid recovery pipe 17; the clear liquid recovery tank 7 is located directly below the clear liquid recovery pipe 16, and the concentrated liquid recovery tank 8 is located directly below the concentrated liquid recovery pipe 17, and the tops of the clear liquid recovery tank 7 and the concentrated liquid recovery tank 8 are both open.

[0025] In this embodiment, the raw liquid tank 1 is used to store the acidic waste liquid to be treated, and a valve for controlling the flow of the raw liquid is provided on the liquid outlet pipe 10 at the bottom thereof. In addition, in order to prevent the acidic liquid in the raw liquid tank 1 from volatilizing, a respirator 20 is also provided on the top of the raw liquid tank 1 to prevent the volatile acidic liquid from volatilizing into the air and causing harm to the operator and the surrounding environment.

[0026] The first circulation pump 2 and the second circulation pump 4 are used to transport the waste liquid in the raw liquid tank to the filter 3 and the filter membrane 5 respectively. The first circulation pump 2 and the second circulation pump 4 both adopt acid-resistant diaphragm pumps. The diaphragm pumps have strong self-priming ability and do not need to be manually started, which can reduce the operation steps and greatly reduce the probability of workers coming into contact with acidic liquids. Moreover, when transporting fluids, the acid-resistant diaphragm pumps can completely isolate the materials from the outside world, greatly avoiding leakage during the transportation of corrosive fluids, thereby reducing occupational hazards.

[0027] The filter membrane adopts an acid-resistant nanofiltration membrane or an acid-resistant reverse osmosis membrane. In practical applications, a suitable acid-resistant nanofiltration membrane or acid-resistant reverse osmosis membrane can be selected for water treatment according to the type and substance content of the wastewater to be treated.

[0028] At the same time, in order to reduce the influence of pressure fluctuations on the acid-resistant diaphragm pump when transporting liquid, an energy accumulator 21 is also provided on the second liquid inlet pipe 13 and the fourth liquid inlet pipe 15 .

[0029] The heat exchanger 6 is used to reduce the large amount of heat generated by the acid-resistant diaphragm pump when conveying liquid, so as to reduce the temperature of the liquid. Considering that acidic liquid may leak during the replacement of the filter membrane 5 and the heat exchanger 6, in this embodiment, the filter membrane 5 and the heat exchanger 6 are both placed vertically, and a clear liquid recovery pipe 16 and a clear liquid recovery tank 7 are provided below the filter membrane 5, and a concentrated liquid recovery pipe 17 and a concentrated liquid recovery tank 8 are provided below the heat exchanger 6; the clear liquid recovery pipe 16 can make the liquid in the filter membrane 5 flow out as much as possible under the action of gravity, and the clear liquid recovery tank 7 is used to recover the acidic liquid flowing out of the clear liquid recovery pipe 16. Similarly, the concentrated liquid recovery pipe 17 and the concentrated liquid recovery tank 8 are used to recover all the acidic liquid in the heat exchanger 6 as much as possible to avoid leakage of acidic liquid during disassembly, thereby causing occupational hazards to the operator.

[0030] In this embodiment, a cleaning pipe 22 whose circulation is controlled by a valve is further provided at the connection point between the connecting pipe 11 and the first liquid inlet pipe 12 through a three-way structure, and clean water can be introduced into the raw liquid tank 1 through the cleaning pipe 22 .

[0031] In order to realize the function of flushing the filter membrane 5 and the heat exchanger 6, a bypass pipe 23 is arranged in parallel on the third liquid inlet pipe 14 and the fourth liquid inlet pipe 15. The clean water in the raw liquid tank 1 can be directly drawn by the first circulation pump 2 through the filter 3, the bypass pipe 23, and the fourth liquid inlet pipe 15 to enter the filter membrane 5 and the heat exchanger 6.

[0032] In order to avoid hidden risks during operation, a protective cover 24 is installed at the top of the membrane shell of the filter membrane 5 in this embodiment to prevent the membrane shell from rupturing due to excessive pressure inside the membrane shell due to operational errors, causing acidic liquid to splash and cause safety accidents.

[0033] In order to control the flow direction of the liquid, valves for controlling the flow of the liquid are installed on the first liquid inlet pipe 12, the bypass pipe 23, the clear liquid recovery pipe 16, the concentrated liquid recovery pipe 17, the clear liquid outlet pipe 18, and the concentrated liquid outlet pipe 19.

[0034] In order to improve the corrosion resistance of the entire filtering device, the connecting pipe 11 adopts a PTFE tube, and other components are also made of acid-resistant materials. Different acid-resistant materials can be used according to the pH value of different stock solutions. For example, 316L stainless steel is suitable for sulfuric acid below 50 degrees Celsius with a concentration of less than 10%, hydrofluoric acid below 10%, nitric acid below 20 degrees Celsius with a concentration of less than 65%, and oxalic acid below 20 degrees Celsius with a concentration of less than 50%; 2205 stainless steel is suitable for sulfuric acid below 60 degrees Celsius with a concentration of less than 20%. Compared with 316L, 2205 stainless steel is more resistant to corrosion by acidic liquids such as nitric acid and phosphoric acid; for acidic liquids such as hydrochloric acid, 2507 stainless steel, glass fiber reinforced plastics, Hastelloy, PE and PPR materials can be used. In order to avoid pressure problems causing pipeline rupture and thus acid leakage, high-pressure clamps are used at each pipeline connection of this embodiment.

[0035] In order to improve the applicability of the filtering device provided in this embodiment, the first circulating pump 2, the filter 3, the second circulating pump 4, the filter membrane 5, the heat exchanger 6, the clear liquid recovery tank 7, the concentrated liquid recovery pipe 8 and the control cabinet 9 of this embodiment are all arranged on the frame 25, and rollers 26 are arranged at the bottom of the frame 25. The whole set of filtering equipment can be moved under the load-bearing action of the frame 25 to meet the needs of wastewater treatment in different scenarios.

[0036] When the filtering device provided by the utility model treats waste water, the valves on the cleaning pipe 22, the bypass pipe 23, the clear liquid recovery pipe 16 and the concentrated liquid recovery pipe 17 are first closed, and then the valve on the liquid outlet pipe 10 is opened, and the first circulation pump 2 and the second circulation pump 4 are started to transport the raw liquid in the raw liquid tank to the filter 3 and the filter membrane 5 in sequence. The clear liquid formed after the raw liquid is filtered by the filter membrane 5 is discharged through the clear liquid outlet pipe 18, and the concentrated liquid formed after filtration enters the heat exchanger 6 through the connecting pipeline between the filter membrane 5 and the heat exchanger 6. After the concentrated liquid is cooled, it flows out from the concentrated liquid outlet pipe 19 at the bottom of the heat exchanger 6, and the concentrated liquid outlet pipe can be connected to the raw liquid tank 1, so that the concentrated liquid enters the raw liquid tank 1 for circulation filtration.

[0037] When cleaning the filter membrane 5 and the heat exchanger 6, first add clean water into the stock liquid tank 1 through the cleaning pipe 22, then close the valves on the cleaning pipe 22, the clean liquid recovery pipe 16 and the concentrated liquid recovery pipe 17, then open the valve on the liquid outlet pipe 10, start the first circulation pump 2, and the clean water enters the filter membrane 5 and the heat exchanger 6 through the filter 3, the bypass pipe 23, and the fourth liquid inlet pipe 15 in turn, and is finally discharged from the clean liquid outlet pipe 18 and the concentrated liquid outlet pipe 19 to complete the cleaning.

[0038] It should be noted that although the above embodiments have been described in this article, this does not limit the scope of patent protection of the utility model. Therefore, based on the innovative concept of the utility model, changes and modifications to the embodiments described herein, or equivalent structural or equivalent process transformations made using the contents of the utility model specification and drawings, directly or indirectly applying the above technical solutions to other related technical fields, are all included in the scope of patent protection of the utility model.

Claims

1. An acid-resistant nanofiltration and reverse osmosis membrane filtration device, characterized in that: The invention comprises a raw liquid tank, a first circulation pump, a filter, a second circulation pump, a filter membrane, a heat exchanger, a clear liquid recovery tank, a concentrated liquid recovery tank and a control cabinet, wherein the raw liquid tank is connected to the first circulation pump through a liquid outlet pipe, a connecting pipe and a first liquid inlet pipe in sequence, the first circulation pump is connected to the filter through the second liquid inlet pipe, the filter is connected to the second circulation pump through the third liquid inlet pipe, the second circulation pump is connected to the filter membrane through the fourth liquid inlet pipe, and the lateral bottom of the filter membrane is connected to the top of the heat exchanger through a pipeline; a clear liquid recovery pipe and a concentrated liquid recovery pipe are respectively provided at the bottom of the filter membrane and the heat exchanger, a clear liquid water outlet pipe is provided on the clear liquid recovery pipe, and a concentrated liquid water outlet pipe is provided on the concentrated liquid recovery pipe; the clear liquid recovery tank is located directly below the clear liquid recovery pipe, and the concentrated liquid recovery tank is located directly below the concentrated liquid recovery pipe; valves are provided on the liquid outlet pipe, the clear liquid recovery pipe, the concentrated liquid recovery pipe, the clear liquid water outlet pipe and the concentrated liquid water outlet pipe.

2. The filtering device according to claim 1, characterized in that: The filtration membrane is an acid-resistant nanofiltration membrane or an acid-resistant reverse osmosis membrane.

3. The filtering device according to claim 1, characterized in that: The second liquid inlet pipe and the fourth liquid inlet pipe are both provided with energy accumulators.

4. The filtering device according to claim 1, characterized in that: A cleaning pipe whose circulation is controlled by a valve is provided at the connection between the connecting pipe and the first liquid inlet pipe.

5. The filtering device according to claim 1, characterized in that: A protective cover is arranged above the filter membrane.

6. The filtering device according to claim 1, characterized in that: The connecting tube is a polytetrafluoroethylene tube.

7. The filtering device according to claim 1, characterized in that: A respirator is arranged on the top of the raw liquid tank.

8. The filtering device according to claim 1, characterized in that: The first circulation pump, the filter, the second circulation pump, the filter membrane, the heat exchanger, the clear liquid recovery tank, the concentrated liquid recovery pipe and the control cabinet are all arranged on a frame, and a roller is arranged at the bottom of the frame.

9. The filtering device according to claim 1, characterized in that: A bypass pipe whose flow is controlled by a valve is arranged in parallel on the third liquid inlet pipe and the fourth liquid inlet pipe.

10. The filtering device according to claim 1, characterized in that: The first circulation pump and the second circulation pump are both acid-resistant diaphragm pumps.

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