Impinging stream vibrating membrane separation device

Abstract

The utility model relates to the technical field of sewage treatment, in particular to an impinging stream vibrating membrane separation device which is characterized in that a sewage pretreatment unit is respectively connected with two porous baffles in a separation unit through two input pipelines, and pores in the porous baffles and a plurality of MOFs (Metal-Organic Frameworks) separation membrane pipes are communicated with sewage; the separated sewage enters a gap between a large pipe and an MOFs separation membrane pipe in the separation unit, and is discharged based on a separated product outlet pipe connected with the upper part of the separation unit; and the separated product outlet pipe is connected with the upper part of the separation unit through two output pipelines. According to the device, insoluble and soluble pollutants can be simultaneously removed by one device, which can be solved by other two or more devices in the prior art. For example, insoluble impurities are difficult to remove by the MOFs membrane, and soluble impurities cannot be removed when the impinging stream technology is used for fluid filtration.

Description

Technical Field

[0001] The utility model relates to the technical field of sewage treatment, in particular to an impinging stream vibration membrane separation device. Background Technique

[0002] Common sewage treatment separation technologies include: membrane separation method, centrifugation method, adsorption method, etc.

[0003] Among them, the MOFs membrane separation method is a new technology that takes the separation membrane as the core and separates and purifies substances with a driving device (such as a pressure pump). MOFs have an extremely large specific surface area and a very high adsorption rate. The selective permeability of the separation membrane is related to the adsorption and diffusion of components in the membrane. Originally insoluble impurities are directly blocked by the MOFs membrane, allowing the solution to pass through. Originally soluble impurities, such as organic substances and metal ions, can be adsorbed and oxidized by the MOFs membrane and removed. Some MOFs membrane engineering designs are simple, efficient, low-cost, have a high reuse rate, and are environmentally friendly, meeting the current sustainable development strategy of the country. They have been widely used in many fields, such as seawater desalination, industrial wastewater treatment, gas separation, blood purification, etc.

[0004] However, although the MOFs membrane has an extremely high specific surface area and can efficiently degrade organic substances and adsorb metal ions, due to its too small pore size, it is difficult to filter condensed substances. That is, it has a good removal effect on soluble pollutants, but it is difficult to remove insoluble impurities. Instead, due to its too small pore size, it is easily blocked, resulting in a significant reduction in the service life of the membrane and an unsatisfactory application effect. Therefore, how to improve the sewage separation effect based on the MOFs membrane has become an urgent technical problem to be solved currently. Content of the Utility Model

[0005] The purpose of the utility model is to provide an impinging stream vibration membrane separation device to solve the above technical problems.

[0006] To achieve the above purpose, the utility model provides an impinging stream vibration membrane separation device, which includes: a sewage pretreatment unit, a separation unit, and a separated product outlet pipe; the separation unit includes: two porous baffles with a height difference, a plurality of MOFs separation membrane tubes arranged between the two porous baffles, and a plurality of large tubes, and the plurality of large tubes surround the plurality of MOFs separation membrane tubes, and a sedimentation area arranged below the bottom porous baffle;

[0007] Among them, the sewage pretreatment unit is connected to the two porous baffles through two input pipes respectively; the pores in the porous baffles communicate with the plurality of MOFs separation membrane tubes; the separated product outlet pipe is connected to the upper part of the separation unit through two output pipes for discharging the separated sewage.

[0008] The technical effects and advantages of the utility model:

[0009] 1. A device that can remove both insoluble and soluble pollutants simultaneously is realized, which requires two or more devices in the prior art to solve. For example, it is difficult for MOFs membranes to remove insoluble impurities, and the impinging stream technology for fluid filtration cannot remove soluble impurities. MOFs membranes themselves have high mechanical strength and elasticity, which are suitable for the impinging stream technology, and the impinging stream technology effectively solves the problem that the small pore size of MOFs membranes is easily blocked; while this new type of MOFs membrane effectively solves the problem that the impinging stream alone cannot remove soluble impurities when applied to other membranes.

[0010] 2. Based on the high mechanical strength of the MOFs membrane, a high-pressure backwashing system is matched to avoid cumbersome pretreatment, and it also breaks through the taboo that compressed air must never contact the membrane theoretically and practically, solving the problem of membrane blockage. It ensures the separation performance of the membrane and extends the service life of the membrane.

[0011] 3. The key to the high degradation rate of ZIF-67 / PAN is that ZIF-67 nanoparticles cannot be embedded in the PAN layer. We use the electrospinning-in-situ growth method to ensure its high degradation rate while solving the material curing problem. Mix the MOFS precursor Co 2+ ions with PAN and electrospin to obtain Co 2+ / PAN fiber thin film; secondly, immerse the obtained Co 2+ / PAN into the organic ligand 2-methylimidazole solution, and through in-situ growth, obtain the in-situ-ZIF-67 / PAN fiber thin film.

[0012] Other features and advantages of the present utility model will be described in the subsequent description, and some of them will be obvious from the description or understood by implementing the present utility model. The objectives and other advantages of the present utility model can be achieved and obtained through the structure pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of an impinging stream vibration membrane separation device;

[0014] Reference numerals: 1 - PAC liquid storage tank; 2 - sewage inlet; 3 - mixing chamber; 4, stirrer; 5 - cyclone separator; 6 - pump; 7 - large pipe; 8 - MOFs separation membrane tube; 9 - resin sealing layer; 10 - porous baffle; 11 - sedimentation area; 12 - baffle; 13 - compressed gas inlet control valve; 14 - separation product outlet control valve; 15 - chemical backwashing outlet control valve; 16 - sewage inlet control valve; 17 - coagulated phase outlet control valve; 18 - separation product outlet pipe; 19 - flowmeter; 20 - water outlet pipe; 21 - metal ion detector; 22 - COD on-line detector; 23 - water outlet. Detailed implementation mode

[0015] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0016] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those who are familiar with this technology to understand and read, and are not used to limit the limited conditions under which the present invention can be implemented. Therefore, they do not have technical essential significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the efficacy that the present invention can produce and the purpose that can be achieved, should still fall within the scope that the technical content disclosed by the present invention can cover. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" cited in this specification are only for the convenience of clear narration, rather than used to limit the scope under which the present invention can be implemented. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the scope under which the present invention can be implemented.

[0017] The impinging stream technology is a new type of fluid flow technology that can be used for filtration. The vibration generated by the impinging of counter-flow fluids can greatly reduce the problem of insoluble substances clogging the membrane pores. However, the single impinging stream technology is only applicable to heterogeneous filtration, that is, it has an efficient effect on insoluble impurities, but has no effect on soluble impurities. Coupled with the fact that the MOFs membrane has a good removal effect on soluble pollutants, it is difficult to remove insoluble impurities, and it will also be blocked due to its too small pore size, resulting in a significant reduction in the service life of the membrane. Therefore, this application proposes an impinging stream vibration membrane separation device.

[0018] The impinging stream vibration membrane separation device combines the impinging stream technology and the membrane separation technology efficiently. The membrane separation component uses the basic principle of the impinging stream to generate eddy currents and vibrations in the fluid at the same time. When two equal-phase fluids flow countercurrently along the same axis and impinge and oscillate at the midpoint, a highly turbulent impinging zone will be formed between the two acceleration tubes, greatly strengthening the transfer process. The solid particles are always in a moving state during the separation process, away from the membrane pores, alleviating the blockage of the particles in the membrane pores. At the same time, the positions and heights of the feed inlet and the discharge outlet, and the distribution of the impinging stream zone and the separation zone are studied, and a solid particle channel is designed. Under the action of gravity, the solid particles will accumulate and settle to the lower end of the device and be discharged from the slag discharge port.

[0019] Due to the high mechanical strength and high pressure resistance of the MOFs membrane used, a suitable backwashing and backflushing system can be assembled, completely solving the problem of membrane fouling, ensuring the separation performance of the membrane, and greatly extending the service life and maintenance cycle of the separation membrane. The impinging streams of the two feeds can also accelerate the separation rate and improve the separation efficiency.

[0020] The following Figure 1 will explain the impinging stream vibrating membrane separation device in detail.

[0021] An impinging stream vibrating membrane separation device, the device includes: a sewage pretreatment unit, a separation unit, and a separated product outlet pipe 18; the separation unit includes: two porous baffles 10 with a height difference, a plurality of MOFs separation membrane tubes 8 and a plurality of large tubes 7 arranged between the two porous baffles, and the plurality of large tubes surround the plurality of MOFs separation membrane tubes, and a settling zone 11 arranged below the bottom porous baffle;

[0022] Among them, the sewage pretreatment unit is connected to the two porous baffles 10 through two input pipes respectively; the pores in the porous baffles 10 communicate with the plurality of MOFs separation membrane tubes 8; the separated product outlet pipe 18 is connected to the upper part of the separation unit through two output pipes for discharging the separated sewage.

[0023] Specifically, the separation unit further includes: a baffle 12 arranged in the upper part of the settling zone 11, a coagulated phase outlet arranged at the bottom of the settling zone, a coagulated phase outlet pipe connected to the coagulated phase outlet, and a coagulated phase outlet control valve 17 arranged on the coagulated phase outlet pipe;

[0024] Among them, the baffle is used to collect insoluble impurities near the coagulated phase outlet; the coagulated phase outlet control valve is used to control the discharge of the coagulated phase precipitate.

[0025] Specifically, the separation unit further includes: sewage inlet control valves 16 are respectively arranged on the two input pipes for controlling the entry of sewage.

[0026] Specifically, the device further includes: a compressed gas inlet control valve 13 and a chemical backwashing outlet control valve 15 are respectively arranged on the two output pipes, a separated product outlet control valve 14 is arranged at the inlet of the separated product outlet pipe 18, and a flow meter 19 is arranged in the rear section of the separated product outlet pipe 18;

[0027] Among them, the compressed gas inlet control valve is used to provide the compressed air required for membrane cleaning; the chemical backwashing outlet control valve is used to control the entry and exit of the chemicals required for membrane cleaning; the flow meter is used to detect the flow rate of the separated sewage.

[0028] Specifically, the device further includes: a water outlet pipe 20 connected to the separation product outlet pipe 18, and a metal ion detector 21 and a COD on-line detector 22 are arranged on the water outlet pipe;

[0029] Among them, the metal ion detector is used to detect the metal ion content in the separated sewage; the COD on-line detector is used to detect the COD content in the separated sewage.

[0030] Specifically, the sewage pretreatment unit includes: a mixing chamber 3, a PAC storage tank 1 and a cyclone separator 5 connected to the mixing chamber, and a sewage inlet 2 arranged on the mixing chamber;

[0031] Among them, the PAC storage tank is used to store PAC; the mixing chamber is used to mix sewage and PAC; the cyclone separator is used to centrifugally separate the sewage mixed in the mixing chamber.

[0032] Specifically, the sewage pretreatment unit further includes: a stirrer 4 arranged in the mixing chamber, preferably a 28-stirrer, for stirring sewage and PAC.

[0033] Specifically, the sewage pretreatment unit further includes: a pump 6 for supplying the sewage centrifugally separated by the cyclone separator to two input pipes.

[0034] Specifically, the MOFs separation membrane tube and the large tube are separated by a resin sealing layer 9.

[0035] Specifically, the membrane in the MOFs separation membrane tube is a ZIF-67PAN composite membrane.

[0036] For the impinging stream vibration membrane separation device provided by the present utility model, due to the high specific surface area but small pore diameter of the MOFs membrane, it has only advantages in cooperation with the impinging stream. The large specific surface area has a very high removal rate of metal ions and organic substances; the small pore diameter just filters insoluble impurities very thoroughly, and some impurities with smaller particle sizes that cannot be filtered by ordinary filter membranes can also be removed, and the problem of blockage is greatly avoided by using the impinging stream. Generally speaking, the removal rates of insoluble and soluble impurities are very high, which is difficult to match the sum of two separate devices.

[0037] To better understand this solution, the following is the operation logic of the device:

[0038] When treating sewage, the PAC storage tank 1 and the sewage inlet 2 respectively feed PAC and sewage into the mixing chamber 3 through pipelines, and after being evenly mixed by the agitator 4 at the bottom of the mixing chamber 3, they are input into the cyclone separator 5; the large precipitates formed after pretreatment are centrifugally separated by the cyclone separator 5, and the separated sewage is shunted into two pipelines by the pump 6. One pipeline is connected to the upper side of the separation unit, and the other pipeline is connected to the lower side of the separation unit. A sewage inlet control valve 16 is added when the lower pipeline approaches the separation device, and then the valve is divided into two pipelines and directly leads to the lower porous baffle 10 and enters multiple MOFs separation membrane tubes 8. The other pipeline that goes upward leads to the upper porous baffle 10, and a sewage inlet control valve 16 is added near the porous baffle 10. After sewage is introduced into both the upper and lower sides, sewage treatment begins.

[0039] It should be noted that the pores of each MOFs separation membrane tube and the porous baffle are connected to the sewage, and the sewage does not enter the voids between the large tube and the MOFs separation membrane tube.

[0040] The treated sewage enters the void between the large tube and the MOFs separation membrane tube, and then is discharged through two pipelines on the upper side of the separation device. Compressed gas inlet control valves 13 and chemical agent backwashing outlet control valves 15 are added to the two pipelines, and then the two pipelines converge into one pipeline under the separation product outlet control valve 14, that is, the separation product outlet pipe 18. A flow meter 19 is added to the separation product outlet pipe 18, and then it is connected to the water outlet pipe 20, and a metal ion detector 21 and a COD on-line detector 22 are set on the water outlet pipe 20, and finally it is discharged from the water outlet 23. The filtered coagulated phase impurities fall from the multiple MOFs separation membrane tubes into the sedimentation area 11, and then are discharged from the pipeline connecting the coagulated phase outlet pipeline.

[0041] It should be noted that when treating sewage, the compressed gas inlet control valve 13, the chemical agent backwashing outlet control valve 15, and the coagulated phase outlet control valve 17 need to be closed. The sewage naturally fills the MOFs separation membrane tubes, and then passes through the MOFs tubular membrane wall filtration into the voids between the large tube and the small tube, and then enters the two water outlet pipes above the separation unit. The remaining coagulated phase impurities after filtration are deposited in the sedimentation area. After the membrane has been operating for a period of time, a certain amount of coagulated phase impurities have also accumulated, and the membrane also needs to be cleaned.

[0042] When cleaning the membrane, the sewage inlet control valve 16 is closed, and the chemical agent backwashing outlet control valve 15, the compressed gas inlet control valve 13, and the coagulated phase outlet control valve 17 are opened. Cleaning agents and high-pressure gas are introduced to clean the membrane and dredge the blocked membrane pores, and then the impurities and waste water are discharged from the coagulated phase outlet control valve 17. After the cleaning is completed, continue to treat sewage as described above.

[0043] Finally, it should be noted that the above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. An impinging flow vibrating membrane separation device, characterized in that: The device comprises: a sewage pretreatment unit, a separation unit, and a separation product outlet pipe; the separation unit comprises: two porous baffles with a height difference, a plurality of MOFs separation membrane tubes and a plurality of large tubes arranged between the two porous baffles, wherein the plurality of large tubes surround the plurality of MOFs separation membrane tubes, and a sedimentation zone arranged below the bottom porous baffle; Among them, the sewage pretreatment unit is connected to two porous baffles through two input pipes respectively, and the pores in the porous baffles, multiple MOFs separation membrane tubes and sewage are connected; the separated sewage enters the gap between the large pipe and the MOFs separation membrane tube, and is discharged based on the separation product outlet pipe connected to the upper part of the separation unit; the separation product outlet pipe is connected to the upper part of the separation unit through two output pipes.

2. The device according to claim 1, characterized in that The separation unit further comprises: a baffle plate disposed at the upper portion of the settling zone, a condensed phase outlet disposed at the bottom of the settling zone, a condensed phase outlet pipeline connected to the condensed phase outlet, and a condensed phase outlet control valve disposed on the condensed phase outlet pipeline; The baffle is used to collect insoluble impurities near the condensed phase outlet; the condensed phase outlet control valve is used to control the discharge of condensed phase precipitation.

3. The device according to claim 1, characterized in that The separation unit also includes: sewage inlet control valves are respectively arranged on the two input pipes to control the entry of sewage.

4. The device according to claim 1, characterized in that The device further comprises: a compressed gas inlet control valve and a reagent backwash outlet control valve are respectively arranged on two output pipelines, a separated product outlet control valve is arranged at the inlet of the separated product outlet pipe, and a flow meter is arranged at the rear section of the separated product outlet pipe; Among them, the compressed gas inlet control valve is used to provide the compressed air required for membrane cleaning; the reagent backwash outlet control valve is used to control the inlet and outlet of the reagent required for membrane cleaning; and the flow meter is used to detect the flow of the separated sewage.

5. The device according to claim 1, characterized in that The device also includes: a water outlet pipe connected to the separated product outlet pipe, a metal ion detector and a COD online detector arranged on the water outlet pipe; Among them, the metal ion detector is used to detect the metal ion content in the separated sewage; the COD online detector is used to detect the COD content in the separated sewage.

6. The device according to claim 1, characterized in that The sewage pretreatment unit comprises: a mixing chamber, a PAC medicine storage tank and a cyclone separator connected to the mixing chamber, and a sewage inlet arranged on the mixing chamber; Among them, the PAC storage tank is used to store PAC; the mixing chamber is used to mix sewage and PAC; and the cyclone separator is used to centrifugally separate the sewage mixed in the mixing chamber.

7. The device according to claim 6, characterized in that The sewage pretreatment unit further includes: a stirrer arranged in the mixing chamber, for stirring the sewage and the PAC.

8. The device according to claim 6, characterized in that The sewage pretreatment unit further comprises: a pump, which is used to supply the sewage centrifugally separated by the cyclone separator into the two input pipes.

9. The device according to claim 1, characterized in that The MOFs separation membrane tube and the large tube are separated by a resin sealing layer.

10. The device according to claim 1, characterized in that The membrane in the MOFs separation membrane tube is a ZIF-67PAN composite membrane obtained by electrospinning-in situ growth method.

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