A membrane separation method waste liquid extraction system applied to NMP

Abstract

The application relates to the field of NMP waste liquid treatment, and particularly discloses a membrane separation method waste liquid extraction system applied to NMP, which comprises a pretreatment tank, a filter tank and a liquid storage tank, a water pump is connected in the pretreatment tank, one end of the water pump is connected with the filter tank, the filter tank comprises a front cover, a tank body, a rear cover and a filter membrane sleeve, a sleeve fixing frame is arranged on the inner wall of the tank body, the sleeve fixing frame is used for fixing the filter membrane sleeve, a sleeve mounting seat is arranged in the front cover, the sleeve mounting seat is a hollow structure, a fixed seat connecting pipe is rotationally connected to a water inlet hole of the sleeve mounting seat, the fixed seat connecting pipe is fixedly connected with a water inlet of the front cover, a plurality of sleeve connecting seats are arranged on a water outlet hole of the sleeve mounting seat, a partition plate is arranged in the sleeve mounting seat, a connecting rod is arranged at the bottom of the partition plate, the connecting rod is fixed with the fixed seat connecting pipe, a first through hole is arranged in the middle of the rear cover, a rotating disc is rotationally connected to the middle of the first through hole, a plurality of second through holes are arranged on the rotating disc, the front end of the filter membrane sleeve is screw-connected with the sleeve connecting seat, and the rear end penetrates through the second through hole; by arranging a plurality of filter membrane sleeves in the filter tank, and then arranging a sleeve fixing seat with a hollow structure to be communicated with the water inlet of the filter tank, the plurality of filter membrane sleeves are respectively communicated with a plurality of water outlet holes on the sleeve fixing seat; when the filter membrane sleeve needs to be replaced, the plurality of filter membrane sleeves can be replaced one by one, and the filtration work of the NMP solution can be continued during the replacement, so that the work efficiency is improved.

Description

TECHNICAL FIELD

[0001] The application relates to the field of NMP waste liquid treatment, and particularly relates to a membrane separation method waste liquid extraction system applied to NMP. BACKGROUND

[0002] NMP, full name N-methyl-2-pyrrolidone, is a commonly used organic solvent, which has good solubility and thermal stability. However, in the use process, NMP will be gradually polluted by impurities and become waste liquid, which not only leads to waste of resources, but also brings adverse effects to the environment. Therefore, the NMP waste liquid needs to be recycled and treated.

[0003] The recycling of NMP waste liquid mainly has physical and chemical methods. The physical methods include distillation, extraction, membrane separation and the like, and the chemical methods include reduction, oxidation and the like. The membrane separation method is to separate and recycle the pollutants in the NMP waste liquid through a membrane separator by adopting reverse osmosis, ultrafiltration membrane and the like. The method has the advantages of simple operation and good recycling effect.

[0004] A method and device for recycling N-methyl-2-pyrrolidone waste gas in lithium battery production by a membrane separation method (patent No. CN107626186A) introduces a method and equipment for recycling NMP waste liquid by a membrane separation method. However, it is found in the use process of the equipment that the filtering operation needs to be stopped to replace the filter membrane, which will lead to a reduction in filtering efficiency. Therefore, an NMP waste liquid filtering device capable of replacing the filter membrane without stopping the filtering operation in the filtering process is needed. SUMMARY

[0005] The application is to solve the technical problems mentioned in the background and proposes the following technical solutions:

[0006] The application relates to a membrane separation method waste liquid extraction system applied to NMP, which comprises a pretreatment tank, a filter tank and a storage tank, a sedimentation device is arranged in the pretreatment tank, a waste liquid inlet is arranged on one side of the pretreatment tank, a liquid discharge port is arranged at the bottom of the other side of the pretreatment tank, a water pump is connected to the liquid discharge port, one end of the water pump is connected with the liquid discharge port pipeline, the other end of the water pump is connected with the filter tank pipeline, the filter tank comprises a front cover, a tank body, a rear cover and a filter membrane sleeve, the front cover and the rear cover are respectively arranged at the two ends of the tank body, a sleeve fixing frame is arranged on the inner wall of the tank body, the sleeve fixing frame comprises a plurality of sleeve rings and a connecting frame, the sleeve rings are uniformly fixed around the connecting frame, a sliding groove is arranged on the inner wall of the tank body, one side of the sleeve rings is located in the sliding groove, a sleeve mounting seat is arranged on the inner wall of the front cover, a water inlet is arranged at the top of the front cover, the inner wall of the water inlet is a threaded structure, the sleeve mounting seat is a hollow structure, a water inlet hole is arranged at the upper end of the sleeve mounting seat, a fixing seat connecting pipe is arranged on the water inlet hole, the water inlet hole is rotationally connected with the fixing seat connecting pipe, the fixing seat connecting pipe is threadedly connected with the water inlet, a plurality of water outlet holes are arranged at the bottom of the sleeve mounting seat, a sleeve connecting seat is arranged on the water outlet holes, a partition plate is arranged in the sleeve mounting seat, a connecting rod is arranged on one side of the partition plate, the connecting rod is fixedly connected with the fixing seat connecting pipe, a first through hole is arranged in the middle of the rear cover, a rotating disc is rotationally connected in the middle of the first through hole, a plurality of second through holes are arranged on the rotating disc;

[0007] sleeve water inlets and sleeve water outlets are arranged at the front end and the rear end of the filter membrane sleeve respectively, the sleeve water inlets are threadedly connected with the sleeve connecting seats, the sleeve water outlets are located in the second through holes, first installation grooves, second installation grooves and third installation grooves are arranged on the inner wall of the filter membrane sleeve, first filter membranes, second filter membranes and third filter membranes are respectively arranged in the first installation grooves, the second installation grooves and the third installation grooves, a drain pipe is connected with the sleeve water outlets, one end of the drain pipe is connected with the storage tank.

[0008] Preferably, the filter pore sizes of the first filter membranes, the second filter membranes and the third filter membranes decrease in sequence.

[0009] Preferably, an observation window is arranged on the tank body, and identification marks are arranged on the filter membrane sleeve, the positions of the identification marks correspond to the positions of the observation windows.

[0010] Preferably, a permanent magnet is arranged in the filter membrane sleeve and fixed on the inner wall of the filter membrane sleeve.

[0011] Preferably, the inner bottom of the pretreatment tank is in a bevel structure, and a pretreatment groove is arranged on the inner bottom of the pretreatment tank.

[0012] The application has the following beneficial effects:

[0013] 1. The application is characterized in that a plurality of filter membrane sleeves are arranged in the filter tank, a hollow sleeve fixing base is arranged in communication with the water inlet of the filter tank, and the plurality of filter membrane sleeves are in communication with a plurality of water outlets on the sleeve fixing base, so that the plurality of filter membrane sleeves can be replaced one by one, and the NMP solution filtering work can be continued during the replacement, thereby improving the work efficiency.

[0014] 2. The application is characterized in that a fixing base connecting pipe is arranged on the water inlet of the sleeve fixing base, the fixing base connecting pipe is rotationally connected with the sleeve fixing base, a partition plate is arranged in the sleeve fixing base, a connecting rod is arranged below the partition plate, and the connecting rod is fixedly connected with the fixing base connecting pipe, so that the NMP waste liquid can be isolated by the partition plate during the replacement of the filter membrane sleeve, and the NMP waste liquid will not flow out of the water outlet connected with the filter membrane sleeve to be replaced.

[0015] 3. The application is characterized in that an observation window is arranged on the tank body, and identification marks are arranged on the filter membrane sleeves, so that the position of the filter membrane sleeve to be replaced can be identified through the observation window during the replacement, the filter membrane sleeve to be replaced is not above the partition plate, and the NMP waste liquid will not flow out of the water outlet connected with the filter membrane sleeve to be replaced, and the filter membrane sleeve to be replaced can be determined through the identification marks, thereby avoiding replacement errors.

[0016] 4. The application is characterized in that a permanent magnet is arranged on the inner wall of the filter membrane sleeve, so that the metal impurities in the NMP waste liquid can be adsorbed by the permanent magnet, and a large amount of metal impurities will not block the filter membrane during the filtering process, thereby reducing the service life of the filter membrane.

[0017] 5. The application is characterized in that a pretreatment groove is arranged at the bottom of the pretreatment tank, so that the large impurities in the NMP waste liquid will be deposited into the pretreatment groove when the NMP waste liquid enters the pretreatment tank, and the large-particle impurities will not enter the filter membrane sleeve, and the filter membrane will not be blocked or damaged during the membrane filtering. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the application.

[0019] Figure 2 It is Figure 1 an enlarged view of position A in FIG. 1.

[0020] Figure 3 It is Figure 1 an enlarged view of position B in FIG. 1.

[0021] Figure 4 It is an exploded view of the filter tank structure in Example 1 of the application.

[0022] Figure 5 It is a sectional view of the sleeve fixing base in Example 1 of the application.

[0023] Figure 6 is a sectional view of the filter membrane sleeve in the embodiment one of the present application;

[0024] Figure 7 is a schematic view of the filter tank in the embodiment two of the present application;

[0025] Figure 8 is a schematic view of the filter membrane sleeve in the embodiment two of the present application;

[0026] Figure 9 is a sectional view of the filter membrane sleeve in the embodiment three of the present application;

[0027] Figure 10 is a sectional view of the pretreatment tank in the embodiment four of the present application.

[0028] In the figure: 1, pretreatment tank; 1-1, sedimentation device; 1-2, waste liquid inlet; 1-3, liquid outlet; 1-4, pretreatment tank; 2, filter tank; 2-1, front cover; 2-11, water inlet; 2-2, tank body; 2-21, sliding groove; 2-3, rear cover; 2-31, first through hole; 2-4, filter membrane sleeve; 2-41, sleeve water inlet; 2-42, sleeve water outlet; 2-43, first installation groove; 2-44, second installation groove; 2-45, third installation groove; 3, liquid storage tank; 4, sleeve fixing frame; 4-1, sleeve ring; 4-2, connecting frame; 5, water pump; 6, sleeve fixing seat; 6-1, water inlet hole; 6-2, fixing seat connecting pipe; 6-3, water outlet hole; 6-4, sleeve connecting seat; 7, partition plate; 7-1, connecting rod; 9, rotating disc; 9-1, second through hole; 10, first filter membrane; 11, second filter membrane; 12, third filter membrane; 13, drain pipe; 14, observation window; 15, identification mark; 16, permanent magnet. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments.

[0030] In the description of the present application, it is to be understood that the relative terms such as first and second and the like are used merely to differentiate one entity or action from another entity or action, without necessarily requiring or implying that there is any such actual relationship or order between such entities or actions. The terms "fixed connection", "fixed setting" of the connection mode include but not limited to "welding", "riveting", "adhesion", "screw connection". The terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment

[0031] The terms "up", "down", "front", "back", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0032] Embodiment one

[0033] Reference Figures 1-6The utility model relates to a membrane separation method waste liquid extraction system applied to NMP, including pretreatment jar 1, filter jar 2 and liquid storage jar 3, the inside of pretreatment jar 1 is provided with the subsiding device 1-1, pretreatment jar 1 one side is provided with waste liquid inlet 1-2, and pretreatment jar 1 other side bottom is provided with liquid discharge port 1-3, and water pump 5 is connected on liquid discharge port 1-3, and one end of water pump 5 is connected with the pipeline connection of liquid discharge port 1-3, and the other end of water pump 5 is connected with the pipeline connection of filter jar 2, and filter jar 2 includes front cover 2-1, jar body 2-2, rear cover 2-3 and filter membrane sleeve 2-4, and front cover 2-1 and rear cover 2-3 are located at both ends of jar body 2-2 respectively, and sleeve fixing frame 4 is set up on the inner wall of jar body 2-2, and sleeve fixing frame 4 includes a plurality of sleeve rings 4-1 and connecting frame 4-2, a plurality of sleeve rings 4-1 are evenly fixed around connecting frame 4-2, and slide groove 2-21 is set up on the inner wall of jar body 2-2, and a plurality of sleeve rings 4-1 one side is located in slide groove 2-21, and sleeve mounting seat 6 is set up on the inner wall of front cover 2-1, and inlet 2-11 is set up on the top of front cover 2-1, and the inner wall of inlet 2-11 is screw thread structure, and sleeve mounting seat 6 is hollow structure, and the upper end of sleeve mounting seat 6 is provided with water inlet hole 6-1, and fixed seat connecting pipe 6-2 is set up on water inlet hole 6-1, and water inlet hole 6-1 is rotatably connected with fixed seat connecting pipe 6-2, and fixed seat connecting pipe 6-2 is threadedly connected with inlet 2-11, and a plurality of water outlet holes 6-3 are set up on the bottom of sleeve mounting seat 6, and sleeve connecting seat 6-4 is set up on water outlet hole 6-3, and partition plate 7 is set up in sleeve mounting seat 6, and partition plate 7 insulates one third place of sleeve mounting seat 6, and connecting rod 7-1 is set up on the one side of partition plate 7, and connecting rod 7-1 is fixedly connected with fixed seat connecting pipe 6-2, and first through hole 2-31 is set up in rear cover 2-3, and rotating disc 9 is rotatably connected in the middle of first through hole 2-31, and a plurality of second through holes 9-1 are set up on rotating disc 9;

[0034] Sleeve inlet 2-41 and sleeve outlet 2-42 are set up on the front and rear ends of filter membrane sleeve 2-4 respectively, sleeve inlet 2-41 is threadedly connected with sleeve connecting seat 6-4, and sleeve outlet 2-42 is located in second through hole 9-1, and first installation groove 2-43, second installation groove 2-44 and third installation groove 2-45 are set up on the inner wall of filter membrane sleeve 2-4, and first filter membrane 10, second filter membrane 11 and third filter membrane 12 are set up in first installation groove 2-43, second installation groove 2-44 and third installation groove 2-45 respectively, and sleeve outlet 2-42 is connected with drain pipe 13, and one end of drain pipe 13 is connected with liquid storage jar 3.

[0035] Preferably, the filter pore size of the first filter membrane 10, the second filter membrane 11 and the third filter membrane 12 decreases.

[0036] In actual operation, the NMP waste liquid and waste gas enter the pretreatment tank 1 through the waste liquid inlet 1-2 on one side of the pretreatment tank 1, and the NMP gas that has been volatilized in the pretreatment tank 1 is mixed into the NMP waste liquid through the settling device 1-1. The pretreated NMP waste liquid is pumped into the filter tank 2 from the pretreatment tank 1 by the water pump 5. The NMP waste liquid enters the sleeve mounting seat 6 through the water inlet hole 6-1 on the sleeve mounting seat 6 in the filter tank 2, and then enters the filter membrane sleeve 2-4 through the water outlet hole 6-3. The filtered NMP solution enters the liquid storage tank 3 through the sleeve water outlet 2-42 after being filtered layer by layer by the first filter membrane 10, the second filter membrane 11 and the third filter membrane in the filter membrane sleeve 2-4.

[0037] When replacing the filter membrane sleeve 2-4, first rotate the filter membrane sleeve to be replaced to the upper part of the tank body 2-2. At this time, the partition plate 7 in the sleeve mounting seat 6 is located below the sleeve connecting seat 6-4 connected to the filter membrane sleeve 2-4 to be replaced, so that the NMP waste liquid entering the sleeve mounting seat 6 from the water inlet hole 6-1 cannot enter the filter membrane sleeve 2-4 to be replaced from the corresponding sleeve connecting seat 6-4. Then, the filter membrane sleeve 2-4 to be replaced is removed from the sleeve connecting seat 6-4 by rotating, and the filter membrane sleeve 2-4 is taken out from the second through hole 9-1 on the rotating disc 9. A new filter membrane sleeve 2-4 is replaced, the new filter membrane sleeve 2-4 is fixed with the sleeve connecting seat 6-4, the drain pipe 13 is connected, and finally the tank body 2-2 is rotated. The partition plate 7 in the sleeve mounting seat 6 cannot prevent the NMP waste liquid from entering the newly replaced filter membrane sleeve, and the replacement step is completed.

[0038] Example Two

[0039] Referring to Figures 7-8 The difference between this embodiment and Example One is that an observation window 14 is arranged on the tank body 2-2, and an identification mark 15 is arranged on the filter membrane sleeve 2-4. The position of the identification mark 15 corresponds to the position of the observation window 14, which facilitates the identification of the filter membrane sleeve 2-4 to be replaced by the staff during the replacement of the filter membrane sleeve 2-4, and avoids the problem of replacement error.

[0040] Example Three

[0041] Referring to Figure 9 A permanent magnet 16 is arranged in the filter membrane sleeve 2-4 and fixed on the inner wall of the filter membrane sleeve 2-4. The permanent magnet 16 can adsorb metal impurities in the NMP waste liquid, which can prevent the metal impurities from blocking the filter membrane and reducing the service life of the filter membrane.

[0042] Example Four

[0043] Referring to Figure 10The inner bottom of the pretreatment tank 1 is provided with a bevel structure, and the inner bottom of the pretreatment tank 1 is provided with a pretreatment groove 1-4. The metal particles with large mass in the NMP waste liquid can be precipitated in the pretreatment tank through the pretreatment groove 1-4, so that the large metal particles are prevented from entering the filter membrane sleeve 2-4, and the filter membrane is prevented from being damaged or blocked by the metal particles.

Claims

1. A membrane separation waste liquid extraction system for NMP, comprising a pretreatment tank (1), a filtration tank (2), and a storage tank (3), characterized in that, The pretreatment tank (1) is equipped with a settling device (1-1). The settling device is configured to allow the NMP gas that has already volatilized into the pretreatment tank (1) to settle and mix into the NMP waste liquid. A waste liquid inlet (1-2) is provided on one side of the pretreatment tank (1), and a drain outlet (1-3) is provided at the bottom of the other side of the pretreatment tank (1). A water pump (5) is connected to the drain outlet (1-3). One end of the water pump (5) is connected to the drain outlet (1-3) and the other end of the water pump (5) is connected to the filter tank (2). The filter tank (2) includes a front cover (2-1), a tank body (2-2), a rear cover (2-3), and a filter membrane sleeve (2-4). The cover (2-1) and the rear cover (2-3) are located at both ends of the tank body (2-2). A sleeve fixing frame (4) is provided on the inner wall of the tank body (2-2). The sleeve fixing frame (4) includes several collars (4-1) and a connecting frame (4-2). Several collars (4-1) are evenly fixed around the connecting frame (4-2). A sliding groove (2-21) is provided on the inner wall of the tank body (2-2). One side of several collars (4-1) is located in the sliding groove (2-21). The front cover (2-1) is located at the rear end of the tank body (2-2). -1) A sleeve mounting seat (6) is provided on the inner wall. A water inlet (2-11) is provided on the top of the front cover (2-1). The inner wall of the water inlet (2-11) is threaded. The sleeve mounting seat (6) is hollow. A water inlet hole (6-1) is provided at the upper end of the sleeve mounting seat (6). A fixed seat connecting pipe (6-2) is provided on the water inlet hole (6-1). The water inlet hole (6-1) is rotatably connected to the fixed seat connecting pipe (6-2). The fixed seat connecting pipe (6-2) is connected to... The inlet (2-11) is threaded. The bottom of the sleeve mounting base (6) is provided with several outlet holes (6-3). A sleeve connecting seat (6-4) is provided on the outlet hole (6-3). A partition (7) is provided inside the sleeve mounting base (6). A connecting rod (7-1) is provided on one side of the partition (7). The connecting rod (7-1) is fixedly connected to the fixed seat connecting pipe (6-2). The partition (7) is configured to isolate NMP waste liquid during the replacement of the filter membrane sleeve (2-4), so that the NMP waste liquid entering the sleeve mounting base (6) from the inlet hole (6-1) will not flow out from the outlet hole (6-3) connected to the filter membrane sleeve (2-4). A first through hole (2-31) is provided in the middle of the back cover (2-3). A rotating disk (9) is rotatably connected in the middle of the first through hole (2-31). Several second through holes (9-1) are provided on the rotating disk (9). The filter membrane sleeve (2-4) is provided with a sleeve inlet (2-41) and a sleeve outlet (2-42) at its front and rear ends, respectively. The sleeve inlet (2-41) is threadedly connected to the sleeve connecting seat (6-4). The sleeve outlet (2-42) is located in the second through hole (9-1). The inner wall of the filter membrane sleeve (2-4) is provided with a first mounting groove (2-43), a second mounting groove (2-44), and a third mounting groove (2-45). The first mounting groove (2-43), the second mounting groove (2-44), and the third mounting groove (2-45) are respectively provided with a first filter membrane (10), a second filter membrane (11), and a third filter membrane (12). The sleeve outlet (2-42) is connected to a drain pipe (13). One end of the drain pipe (13) is connected to the liquid storage tank (3).

2. The membrane separation waste liquid extraction system for NMP as described in claim 1, characterized in that, The pore sizes of the first filter membrane (10), the second filter membrane (11), and the third filter membrane (12) decrease in that order.

3. The membrane separation waste liquid extraction system for NMP as described in claim 1, characterized in that, An observation window (14) is provided on the tank body (2-2), and an identification mark (15) is provided on the filter membrane sleeve (2-4). The position of the identification mark (15) corresponds to the position of the observation window (14).

4. The membrane separation waste liquid extraction system for NMP as described in claim 1, characterized in that, A permanent magnet (16) is provided inside the filter membrane sleeve (2-4), and the permanent magnet (16) is fixed on the inner wall of the filter membrane sleeve (2-4).

5. The membrane separation waste liquid extraction system for NMP as described in claim 1, characterized in that, The bottom of the pretreatment tank (1) has a sloping structure, and a pretreatment trough (1-4) is provided at the bottom of the pretreatment tank (1).

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