Ultraviolet anti-pollution hollow fiber membrane leachate treatment device and method

Abstract

The invention discloses an ultraviolet anti-pollution hollow fiber membrane leachate treatment device which comprises a hollow fiber membrane assembly, a gas distribution base, a reflecting cover, an ultraviolet lamp tube and a main water outlet pipe, the bottom of the hollow fiber membrane assembly is fixed to the gas distribution base, and the top end of the hollow fiber membrane assembly is fixed to the reflecting cover; the interior of the hollow fiber membrane assembly is communicated with the interior of the reflecting cover, the bottom of the ultraviolet lamp tube is fixed in the top end of the gas distribution base, filtered purified water in the hollow fiber membrane assembly is extracted, the ultraviolet lamp tube irradiates the hollow fiber membrane assembly, and the reflecting cover collects ultraviolet rays irradiated by the ultraviolet lamp tube to the hollow fiber membrane assembly. According to the ultraviolet anti-pollution hollow fiber membrane leachate treatment method, a pretreatment unit, a biochemical treatment unit and a deep treatment unit are included, online cleaning of a hollow fiber membrane in the deep treatment unit is achieved, the maintenance difficulty of a membrane assembly is greatly reduced, the synergistic effect of treatment and cleaning is achieved, and the treatment efficiency of an ultrafiltration membrane is enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of water treatment, and in particular to an ultraviolet resistant hollow fiber membrane leachate treatment device and method. Background Art

[0002] Leachate mainly comes from the liquid produced by the decomposition of garbage in landfills and the infiltrated rainwater, etc. Its components include high concentrations of organic matter, heavy metals, ammonia nitrogen, and various suspended solids and microorganisms.

[0003] The hollow fiber membrane is hollow in the middle, and its tube wall is the membrane layer with separation function. During the filtration process, by applying pressure on one side of the membrane, the small molecular components in the liquid mixture to be treated pass through the membrane wall under the action of pressure, while the large molecular components are retained on the feed side of the membrane.

[0004] Typical landfill leachate treatment processes mainly include "pretreatment + biochemical treatment + membrane deep treatment", "pretreatment + membrane deep treatment" and "pretreatment + physicochemical treatment + biochemical deep treatment". Among them, the process of "pretreatment + biochemical treatment + membrane deep treatment" has become the mainstream method of domestic landfill leachate treatment due to its outstanding pollutant treatment efficiency and stable effluent water quality, and is widely used in various landfill leachate treatment projects. However, the surface of the hollow fiber membrane is prone to adsorption and accumulation of organic matter, which will clog the membrane pores and cause the membrane flux to decrease.

[0005] In this regard, the prior art (CN117069248A) discloses an MBR membrane assembly that uses photocatalytic advanced oxidation for self-cleaning, which uses LED ultraviolet light strips with suitable wavelengths to be evenly added between MBR membranes and a titanium dioxide layer to be added to the exposed part of the MBR membrane support frame, and is supplemented by control logic basic equipment to achieve online automatic physical cleaning based on photocatalytic advanced oxidation. This MBR membrane assembly that uses photocatalytic advanced oxidation for self-cleaning uses the MBR membrane as a carrier to carry out biochemical reactions on its surface, and cannot directly use the MBR membrane for deep filtration to complete deep treatment, so this self-cleaning MBR membrane assembly based on advanced oxidation is not applicable to deep treatment units.

[0006] The above problems are in urgent need of being solved. The present invention provides an ultraviolet resistant hollow fiber membrane leachate treatment device and method for solving the above problems. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a hollow fiber membrane leachate treatment device and method with UV resistance, realize online cleaning of the hollow fiber membrane in the deep treatment unit, greatly reduce the maintenance difficulty of the membrane assembly, realize the synergistic effect of treatment and cleaning, and enhance the ultrafiltration membrane treatment efficiency.

[0008] The technical solution adopted by the present invention to solve its technical problems is: on the one hand, the present invention provides an ultraviolet anti-pollution hollow fiber membrane leachate treatment device including a hollow fiber membrane component, an aeration component arranged at the bottom end of the hollow fiber membrane component, a photocatalytic component arranged in the hollow fiber membrane component and a main water outlet pipe arranged at the top end of the hollow fiber membrane component, the aeration component includes an air distribution base, the photocatalytic component includes a reflector, the bottom of the hollow fiber membrane component is fixed on the air distribution base, the top of the hollow fiber membrane component is fixed to the reflector, the interior of the hollow fiber membrane component is connected with the interior of the photocatalytic component, the bottom of the ultraviolet lamp is fixed in the top of the air distribution base, the filtered water inside the hollow fiber membrane component is extracted, the ultraviolet lamp irradiates the hollow fiber membrane component, and the reflector collects the ultraviolet rays irradiated by the ultraviolet lamp onto the hollow fiber membrane component.

[0009] Preferably, the hollow fiber membrane component is a biomass / titanium dioxide modified PVDF ultrafiltration membrane.

[0010] Preferably, the aeration assembly further comprises an aeration plate disposed at the top of the air distribution base and a main air inlet pipe disposed at the side of the air distribution base, the aeration plate is connected to the air distribution base, and the main air inlet pipe is connected to the air distribution base.

[0011] Preferably, the aeration plate includes an air inlet pipe and an air outlet plate arranged at the upper end of the air inlet pipe. A spring, a gravity ball arranged at the lower end of the spring, a thread arranged on the outer surface of the bottom end of the air inlet pipe, and an air inlet hole arranged in the bottom end of the air inlet pipe are arranged inside the air inlet pipe. One end of the thread abuts against the air outlet plate, and the other end of the thread abuts against the gravity ball. The air outlet plate is evenly distributed with air outlet holes. When air is taken in, the gravity ball moves upward under pressure, the spring shortens, and the air flow enters from the air inlet hole and flows through the air inlet pipe to the air outlet hole.

[0012] Preferably, membrane assembly through holes are evenly opened at the bottom of the reflector, and the membrane assembly through holes are connected to the hollow fiber membrane assembly.

[0013] Preferably, the leachate treatment device further comprises a water outlet pump and a support frame, the water outlet pump is connected to the main water outlet pipe, one end of the support frame is fixedly connected to the reflector, and the other end of the support frame is fixedly connected to the air distribution base.

[0014] Preferably, the hollow fiber membrane assembly is fixed between the air distribution base and the reflector by epoxy resin and flexible sealant.

[0015] Another aspect of the present invention provides a method for treating a leachate of a hollow fiber membrane with UV-resistant pollution, the leachate treating method comprising a pretreatment unit, a biochemical treatment unit and a deep treatment unit;

[0016] The pretreatment unit adds coagulant polyaluminium chloride and flocculant polyacrylamide;

[0017] The biochemical unit adopts BAF (biological aeration filter) technology with a hydraulic retention time of 4h;

[0018] The deep treatment unit adopts the leachate treatment device.

[0019] Preferably, the dosage of polyaluminium chloride is controlled at 100 mg / L;

[0020] The dosage of polyacrylamide is controlled at 1 / 1000 of the solution volume, and the reaction time after the addition of the agent is controlled at 30 minutes.

[0021] The beneficial effects of the invention are: extracting filtered water from the hollow fiber membrane assembly, irradiating the hollow fiber membrane assembly with an ultraviolet lamp, and collecting the ultraviolet rays irradiated by the ultraviolet lamp onto the hollow fiber membrane assembly by a reflector. The hollow fiber membrane assembly in the deep processing unit is cleaned online, which greatly reduces the maintenance difficulty of the hollow fiber membrane assembly, realizes the synergistic effect of processing and cleaning, and enhances the processing efficiency of the ultrafiltration membrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention is preferably described below in conjunction with the accompanying drawings and embodiments.

[0023] In the figure: Figure 1 It is a front view of the leachate treatment device of the present invention;

[0024] Figure 2 for Figure 1 AA cross-sectional view of the landfill leachate treatment device;

[0025] Figure 3 for Figure 2 A partial enlarged view of middle A;

[0026] Figure 4 This is a comparison chart of the raw water from landfill leachate treatment and the water after treatment in the deep treatment unit;

[0027] Figure 5 It is a bar chart of the removal rate of each substance in the pretreatment unit;

[0028] Figure 6 It is a bar chart of the removal rate of each substance in the biochemical unit;

[0029] Figure 7 It is a bar chart of the removal rate of each substance in the deep processing unit;

[0030] Figure 8 This is a line graph showing the changes in the content of various substances in the effluent from the deep treatment unit over time.

[0031] 1. Leachate treatment device; 10. Hollow fiber membrane assembly; 20. Aeration assembly; 21. Aeration plate; 211. Air inlet pipe; 2111. Spring; 2112. Gravity ball; 2113. Thread; 2114. Air inlet hole; 212. Air outlet plate; 2121. Air outlet hole; 22. Main air inlet pipe; 23. Air distribution base; 231. Round seat; 232. Annular groove; 30. Photocatalytic assembly; 31. Ultraviolet lamp; 32. Reflector; 321. Through hole of membrane assembly; 40. Main water outlet pipe; 50. Water outlet pump; 60. Support frame. DETAILED DESCRIPTION

[0032] The embodiments of the present invention will be described in detail below in conjunction with the examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present invention and should not be construed as limiting the scope of the present invention. If specific conditions are not specified in the examples, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0033] like Figure 1-3 As shown, the present invention provides an ultraviolet anti-pollution hollow fiber membrane leachate treatment device 1 including a hollow fiber membrane assembly 10, an aeration assembly 20 arranged at the bottom end of the hollow fiber membrane assembly 10, a photocatalytic assembly 30 arranged in the hollow fiber membrane assembly 10, a main water outlet pipe 40 arranged at the top end of the hollow fiber membrane assembly 10, a water outlet pump 50 connected to the main water outlet pipe 40, and a support frame 60 fixed between the photocatalytic assembly 30 and the aeration assembly 20.

[0034] The hollow fiber membrane component 10 is a biomass / titanium dioxide modified PVDF ultrafiltration membrane. In this solution, the hollow fiber membrane component 10 uses a biomass / titanium dioxide modified PVDF ultrafiltration membrane material in a patent (CN 118577153 A).

[0035] The aeration assembly 20 includes an aeration plate 21 , a main air inlet pipe 22 and an air distribution base 23 .

[0036] The aeration plate 21 is disposed on the top of the air distribution base 23 , and the aeration plate 21 is communicated with the air distribution base 23 .

[0037] like Figure 3As shown, the aeration plate 21 includes an air inlet pipe 211, an air outlet plate 212 arranged at the upper end of the air inlet pipe 211, a spring 2111 is arranged inside the air inlet pipe 211, a gravity ball 2112 is arranged at the lower end of the spring 2111, a thread 2113 is arranged on the outer surface of the bottom end of the air inlet pipe 211, and an air inlet hole 2114 is arranged at the bottom end of the air inlet pipe 211, one end of the thread 2113 is abutted against the air outlet plate 212, and the other end of the thread 2113 is abutted against the gravity ball 2112, and the air outlet plates 212 are evenly distributed with air outlet holes 2121. When air is taken in, the gravity ball 2112 moves upward under pressure, the spring 2111 is shortened, and the air flow enters from the air inlet hole 2114 and flows through the air inlet pipe 211 to the air outlet hole 2121.

[0038] The main air inlet pipe 22 is arranged on the side of the air distribution base 23 , and the main air inlet pipe 22 is communicated with the air distribution base 23 .

[0039] The photocatalytic component 30 includes an ultraviolet lamp tube 31 and a reflector 32 .

[0040] One end of the support frame 60 is fixedly connected to the reflector 32 , and the other end of the support frame 60 is fixedly connected to the air distribution base 23 .

[0041] like Figure 2 As shown, the bottom of the hollow fiber membrane assembly 10 is fixed on the air distribution base 23, the top of the hollow fiber membrane assembly 10 is fixed to the reflector 32, the interior of the hollow fiber membrane assembly 10 is connected to the interior of the photocatalytic assembly 30, and the bottom of the ultraviolet lamp tube 31 is fixed to the top of the air distribution base 23.

[0042] The hollow fiber membrane assembly 10 is fixed between the air distribution base 23 and the reflector 32 by epoxy resin and flexible sealant.

[0043] The present invention provides a method for treating hollow fiber membrane leachate with UV-resistant pollution, comprising a pretreatment unit, a biochemical treatment unit, and a deep treatment unit;

[0044] The pretreatment unit adds coagulant polyaluminium chloride and flocculant polyacrylamide;

[0045] The biochemical unit adopts BAF (biological aeration filter) technology with a hydraulic retention time of 4h;

[0046] The deep treatment unit adopts a leachate treatment device 1.

[0047] The dosage of polyaluminium chloride is controlled at 100mg / L;

[0048] The dosage of polyacrylamide is controlled at 1 / 1000 of the solution volume, and the reaction time after the addition of the agent is controlled at 30 minutes.

[0049] The present invention provides a working process of a hollow fiber membrane leachate treatment device 1 with UV resistance to pollution:

[0050] The concentrated leachate first enters the pretreatment unit, where some large suspended solids and colloids in the leachate are initially adsorbed, coagulated and precipitated. The leachate that has undergone preliminary filtration treatment enters the biochemical treatment unit; the leachate that has undergone biochemical treatment enters the deep treatment unit, where the leachate treatment device 1 is placed in the leachate outlet pool after biochemical treatment, the outlet pump 50 is turned on, and the filtered clean water inside the hollow fiber membrane assembly 10 is extracted, the ultraviolet lamp 31 irradiates the hollow fiber membrane assembly 10, and the reflector 32 collects the ultraviolet rays irradiated by the ultraviolet lamp 31 onto the hollow fiber membrane assembly 10.

[0051] Leachate treatment device 10 reaction conditions: pressure is -1 bar, flow rate is 55 L / m -2 / h, the reaction lasts for 10h.

[0052] The pH determination method adopts the general rules for pH determination of chemical reagents (GB T 9724-2007).

[0053] The determination method of ammonia nitrogen adopts the standard of "Water Quality-Determination of Ammonia Nitrogen-Gas Phase Molecular Absorption Spectrometry" (HJ / T 195-2005);

[0054] Total organic carbon (TOC) adopts the standard of total organic carbon determination in water quality - combustion oxidation - non-dispersive infrared absorption method (HJ 501-2009);

[0055] The chemical oxygen demand (COD) adopts the dichromate method for the determination of chemical oxygen demand in water (HJ 828-2017) standard.

[0056] Table 1: Various indicators of landfill leachate inflow

[0057]

[0058] Table 2: Various indicators of effluent from landfill leachate pretreatment unit

[0059]

[0060] Table 3: Various indicators of effluent from landfill leachate deep treatment unit

[0061]

[0062] Table 4: Various indicators of effluent from landfill leachate deep treatment unit

[0063]

[0064] As shown in Tables 1, 2, 3, and 4, the pretreatment unit achieves the effect of removing ammonia nitrogen, TOC, and COD by coagulating suspended matter and colloidal matter in the water, but the pH will increase to a certain extent during the addition of reagents. The biochemical treatment unit greatly reduces the ammonia nitrogen content in the landfill leachate, and the biochemical treatment unit has a good removal effect on each substance. The deep treatment unit achieves a further reduction in pH through the filtration of salt substances by ultrafiltration membranes.

[0065] According to Tables 1 and 4, Figure 8 It can be seen that the treatment efficiency of the hollow fiber membrane assembly 10 shows a cycle of first decreasing and then increasing as the treatment time changes. This is because under the action of photocatalysis, the substances on the surface of the hollow fiber membrane assembly 10 are degraded, making the hollow fiber membrane assembly 10 anti-pollution capable.

[0066] The ultraviolet resistant hollow fiber membrane leachate treatment device and method of the present invention have at least the following beneficial effects:

[0067] 1. Under the action of ultraviolet light photocatalytic oxidation, organic pollutants are decomposed into small molecules, thereby reducing the blockage of the membrane surface and helping to increase membrane flux. On the other hand, ultraviolet irradiation changes the surface hydrophilicity of the membrane, reducing the resistance of water on the membrane surface, thereby increasing membrane flux.

[0068] 2. The advantages of coupling photocatalysis and ultrafiltration membrane not only have the high removal rate of ultrafiltration membrane, but also improve the flux of ultrafiltration membrane under the synergistic effect of photocatalysis, so that the ultrafiltration membrane has a certain self-purification and anti-pollution ability, thereby realizing the long-term use of ultrafiltration membrane.

[0069] 3. Realize online cleaning of the hollow fiber membrane assembly 10 in the deep processing unit, greatly reduce the maintenance difficulty of the membrane assembly, achieve the synergistic effect of processing and cleaning, and enhance the processing efficiency of the ultrafiltration membrane.

[0070] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A hollow fiber membrane leachate treatment device with UV resistance, characterized in that: The landfill leachate treatment device (1) comprises a hollow fiber membrane assembly (10), an aeration assembly (20) arranged at the bottom end of the hollow fiber membrane assembly (10), a photocatalytic assembly (30) arranged in the hollow fiber membrane assembly (10), and a main water outlet pipe (40) arranged at the top end of the hollow fiber membrane assembly (10), the aeration assembly (20) comprises an air distribution base (23), the photocatalytic assembly (30) comprises a reflector (32), and the bottom of the hollow fiber membrane assembly (10) is fixed on the air distribution base (23). The top of the hollow fiber membrane assembly (10) is fixed to the reflector (32), the interior of the hollow fiber membrane assembly (10) is connected to the interior of the photocatalytic assembly (30), the bottom of the ultraviolet lamp tube (31) is fixed to the top of the air distribution base (23), and the filtered water is extracted from the interior of the hollow fiber membrane assembly (10). The ultraviolet lamp tube (31) irradiates the hollow fiber membrane assembly (10), and the reflector (32) collects the ultraviolet rays irradiated by the ultraviolet lamp tube (31) onto the hollow fiber membrane assembly (10).

2. The ultraviolet pollution-resistant hollow fiber membrane leachate treatment device according to claim 1 is characterized in that: The hollow fiber membrane component (10) is a biomass / titanium dioxide modified PVDF ultrafiltration membrane.

3. The ultraviolet anti-pollution hollow fiber membrane leachate treatment device according to claim 1, characterized in that: The aeration assembly (20) further comprises an aeration plate (21) arranged at the top of the air distribution base (23) and a main air inlet pipe (22) arranged at the side of the air distribution base (23); the aeration plate (21) is in communication with the air distribution base (23), and the main air inlet pipe (22) is in communication with the air distribution base (23).

4. The ultraviolet pollution-resistant hollow fiber membrane leachate treatment device according to claim 3 is characterized in that: The aeration plate (21) comprises an air inlet pipe (211), an air outlet plate (212) arranged at the upper end of the air inlet pipe (211), a spring (2111) arranged inside the air inlet pipe (211), a gravity ball (2112) arranged at the lower end of the spring (2111), a thread (2113) arranged on the outer surface of the bottom end of the air inlet pipe (211), an air inlet hole (2114) arranged in the bottom end of the air inlet pipe (211), and the thread (2113) arranged on the outer surface of the bottom end of the air inlet pipe (211). One end of the thread (2113) is abutted against the air outlet plate (212), and the other end of the thread (2113) is abutted against the gravity ball (2112). The air outlet plate (212) is evenly distributed with air outlet holes (2121). When air is taken in, the gravity ball (2112) moves upward under pressure, the spring (2111) is shortened, and the air flow enters from the air inlet hole (2114) and flows through the air inlet pipe (211) to the air outlet hole (2121).

5. The ultraviolet pollution-resistant hollow fiber membrane leachate treatment device according to claim 1, characterized in that: The bottom of the reflector (32) is evenly provided with membrane assembly through holes (321), and the membrane assembly through holes (321) are in communication with the hollow fiber membrane assembly (10).

6. The ultraviolet pollution-resistant hollow fiber membrane leachate treatment device according to claim 1, characterized in that: The leachate treatment device (1) further comprises a water outlet pump (50) and a support frame (60), wherein the water outlet pump (50) is connected to the main water outlet pipe (40), one end of the support frame (60) is fixedly connected to the reflector (32), and the other end of the support frame (60) is fixedly connected to the air distribution base (23).

7. The ultraviolet pollution-resistant hollow fiber membrane leachate treatment device according to claim 1, characterized in that: The hollow fiber membrane assembly (10) is fixed between the air distribution base (23) and the reflector (32) using epoxy resin and flexible sealant.

8. A method for treating hollow fiber membrane leachate with UV resistance, characterized in that: The invention comprises the ultraviolet anti-pollution hollow fiber membrane leachate treatment device as described in claims 1-7.

9. The method for treating the leachate of hollow fiber membrane with UV resistance according to claim 8, characterized in that: The leachate treatment method comprises a pretreatment unit, a biochemical treatment unit and a deep treatment unit; The pretreatment unit adds coagulant polyaluminium chloride and flocculant polyacrylamide; The biochemical unit adopts BAF (biological aeration filter) technology with a hydraulic retention time of 4h; The deep treatment unit adopts the leachate treatment device (1).

10. The method for treating the leachate of hollow fiber membrane with UV resistance according to claim 9, characterized in that: The dosage of polyaluminium chloride is controlled at 100mg / L; The dosage of polyacrylamide is controlled at 1 / 1000 of the solution volume, and the reaction time after the addition of the agent is controlled at 30 minutes.

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