Membrane separation and concentration system for conductive polymer dispersion liquid

Abstract

The utility model relates to a membrane separation and concentration system for conductive polymer dispersion liquid, which comprises a material barrel, a membrane component, a circulating pump, a thermometer, a pressure gauge, a flow meter, a pipeline and the like, an ultrasonic vibration rod is arranged in a pipeline in front of a multi-impeller circulating pump to apply ultrasonic waves to crush and disperse easy-to-glue mucilage glue in feed liquid so as to prevent a membrane pipe from being blocked, a cooling device and a membrane back-flushing regeneration device are further arranged in the system, so that the temperature is maintained, flux is prevented from being reduced, stable membrane separation is achieved, and the system is suitable for production of concentrated PEDOT: PSS and other conductive polymer dispersion liquid.

Description

Technical Field

[0001] The utility model relates to the technical field of conductive polymer dispersion liquid concentration, in particular to a membrane separation and concentration system for conductive polymer dispersion liquid. Background Technique

[0002] Aqueous dispersions of conductive polymers, including poly(thiophene), poly(pyrrole), polyaniline, etc., are a class of special polymer colloidal feed liquids with conductivity. Among them, the aqueous dispersion of poly(thiophene) accounts for the majority and has wide applications in the optoelectronic field. The poly(thiophene) conductive polymer is mainly based on PEDOT:PSS (poly(3,4-ethylenedioxythiophene): poly(styrenesulfonic acid)) dispersion liquid, and its physical properties are representative of conductive polymer dispersion liquids. After the synthesis and deionization of the functional components of conductive polymers such as PEDOT:PSS dispersion liquid, it is often necessary to concentrate the dispersion liquid to increase the content. The high-content concentrate of PEDOT:PSS dispersion liquid is generally obtained by reprocessing the low-concentration stock solution through vacuum evaporation concentration. For example, in CN109734932A "High-solid-content PEDOT-PSS dispersion liquid and its preparation method" published on May 10, 2019, the obtained reaction solution is filtered to remove salts, and then concentrated by vacuum evaporation to a certain solid-content concentrate, and then homogenized under high pressure to obtain a 1.5% high-solid-content PEDOT:PSS aqueous dispersion liquid. In this vacuum evaporation concentration operation, the evaporation device used is generally a glass bottle for small-scale tests and an evaporation kettle for production. Under heating, part of the water in the dispersion liquid is evaporated, and PEDOT:PSS is concentrated to the required content. However, PEDOT:PSS dispersion liquid is unstable to heating and is prone to deterioration in the evaporator. Even if the temperature and pressure are well controlled, the PEDOT:PSS micelles will adhere to the evaporator wall, especially at the gas-liquid interface, and the wall material will be thermally dried and turned into irreversible impurity particles. Post-treatment is required after concentration, filtering out the generated impurity particles, and then performing high-pressure homogenization treatment. Generally, using a heating evaporation device to concentrate the conductive polymer dispersion liquid will result in losses such as more than 15% dryification, and improvement is urgently needed.

[0003] In view of the disadvantages of thermal concentration of conductive polymers in evaporation devices, it is advisable to change to cold-state concentration. Cold-state concentration easily leads to membrane separation concentration. The colloidal size in the conductive polymer dispersion is 5-200 nanometer micelles. Theoretically, a nanoscale filtration membrane can be used to separate water from the dispersion to achieve concentration. The principle of membrane separation is that under external pressure, the feed solution flows in the channels of the membrane tube (or membrane sheet), and water and small molecules pass through the filtration membrane to form permeate water, while soluble macromolecules and suspended substances are intercepted by the filtration membrane and form a concentrated solution. To increase the concentration, the formed concentrated solution can be returned to the feed barrel, pressurized by a circulation pump and then enter the membrane tube again. In this way, through continuous circulation, the concentration of the intercepted substances will continuously increase, making the circulating liquid reach the required concentration. Directly adopting the existing technology, the inventor used a cross-flow membrane separation device with self-cleaning function to conduct a concentration test on PEDOT:PSS dispersion. The membrane tubes were replaced with microfiltration membranes, ultrafiltration membranes, nanofiltration membranes, and RO membranes, and the membrane materials were changed to organic and inorganic ones. Soon after the PEDOT:PSS feed liquid circulated during concentration, the membrane tubes became blocked. Instead of being concentrated, the PEDOT:PSS component in the feed liquid decreased, and a considerable part of PEDOT:PSS adhered to the membrane tube wall. Analyzing the reasons, conductive polymers are charged micelles and are prone to gelation. During separation, they are easily attracted to and bonded with each other under pressure to form a whole and block the membrane tubes. Therefore, the above technical problems need to be solved when using membrane separation to concentrate conductive polymer dispersions. Summary of the Invention

[0004] In view of the deficiencies of the prior art, the present utility model provides a membrane separation and concentration system for conductive polymer dispersions, which has the function of concentrating conductive polymer dispersions, and at the same time, the system operates stably and reliably, solving the problem of membrane tube blockage when directly using the existing membrane separation device to concentrate conductive polymer dispersions.

[0005] To achieve the above object, the present utility model provides the following technical solutions: 1. A membrane separation and concentration system for conductive polymer dispersions, comprising a feed barrel, a feed barrel cover, a circulation pump, a membrane module, valves, a thermometer, a flow meter, a pressure gauge, and connecting pipes.

[0006] A feed liquid thermometer is provided on the feed barrel. A pipeline before the pump is provided between the outlet of the feed barrel and the inlet of the circulation pump. An outlet valve is provided on the pipeline before the pump. A pipeline after the pump is provided between the outlet of the circulation pump and the inlet of the membrane module. A pressure gauge after the pump is provided on the pipeline after the pump. The membrane module consists of one or more filtration membrane tubes and a shell. The feed liquid flows through the tube side of the membrane module (400), and the permeate water exits from the shell side.

[0007] The shell side of the membrane assembly is connected to a sampling valve and a shell side pipeline, the shell side pipeline is connected to a merging pipeline and a recoil pipeline through a recoil intersection, the recoil pipeline is in communication with a tap water valve and a tap water pipeline, and can be flushed before and after operation, the merging pipeline is connected to a flow pipeline and a water outlet pipeline through a interception intersection, a flow valve and a water permeability flow meter are provided on the flow pipeline, the end of the flow pipeline passes through the barrel cover and extends into the material barrel and can discharge permeate water when metering is required, the water outlet pipeline is provided with a water outlet valve and the end of the water outlet pipeline can often discharge permeate water.

[0008] The outlet of the membrane module is connected to a film outlet pipeline, on which a pressure gauge and a regulating valve are arranged after the membrane, and the film outlet pipeline after the regulating valve is connected to the lower part of the circulation pipeline, and a liquid outlet valve is arranged at the lower end of the circulation pipeline to discharge the concentrated product, and a circulation flow meter is arranged at the upper part of the circulation pipeline, and the upper end of the circulation pipeline extends into the barrel through the barrel cover to discharge the circulating liquid coming through the film outlet pipeline; the specific scheme is:

[0009] a. The circulating pump adopts a multi-stage pump containing multiple impellers.

[0010] b. An ultrasonic vibration rod is arranged in the pump front pipeline between the outlet of the barrel and the inlet of the circulating pump. The outer end of the ultrasonic vibration rod is connected to an ultrasonic generator and a high-frequency power supply device thereof. The ultrasonic generator can emit ultrasonic vibration waves to the material liquid in the pump front pipeline.

[0011] In the current membrane separation and concentration of PEDOT:PSS test, the inventors found that the PEDOT:PSS scale deposited on the membrane tubes can be removed by strong ultrasonic waves when the membrane tubes were removed for cleaning. It is imagined that the best effect is to directly emit ultrasonic waves to the feed liquid entering the membrane assembly, but at this time, a large number of large cavitation bubbles will be generated in the feed liquid, and air resistance will be formed in the small holes of the membrane tubes, preventing the feed liquid from flowing, and the filtration and concentration will not be able to continue. During the exploration, it was unexpectedly discovered that the influence of ultrasonic bubbles on the membrane can be solved by applying ultrasonic waves behind a multi-stage pump with multiple impellers.

[0012] Furthermore, it was also found that by setting an ultrasonic vibration rod in the pipeline at the inlet of the circulation pump, due to the small space in the pipeline through which the material liquid flows, the material liquid can obtain the highest ultrasonic intensity, and the micelles of the conductive polymer can be "sheared" well. Subsequently, the material liquid accompanied by ultrasonic waves enters the circulation pump of the multi-stage pump. The large bubbles generated by the ultrasonic waves are first "repeatedly" dispersed and reduced in size by the multiple impellers of the multi-stage pump. As the impellers rotate centrifugally, the large bubbles in the material liquid are compressed and disappear, turning into countless tiny bubbles evenly dispersed in the material liquid (whereas if a vortex pump or diaphragm pump with the same head is used for the circulation pump, there will still be some large bubbles in the discharged liquid, affecting the flow of the material liquid in the membrane tube). Subsequently, the ultrasonic material liquid accompanied by tiny bubbles enters the small holes of the membrane tube in the membrane module. Perhaps due to the bridging effect of the tiny bubbles and the continuous dispersion effect of the ultrasonic waves, the conductive polymer colloid in the material liquid in the membrane tube is not easily adhered to each other, and the membrane tube is not easily blocked. Based on the above findings, the present utility model was completed.

[0013] Further, 2. Enhancement scheme:

[0014] c, an ultrasonic vibration rod inserted into the material liquid is provided on the lid of the material bucket, and / or

[0015] d, one or more ultrasonic vibration heads are provided on the outer wall of the material bucket. The ultrasonic vibration heads and the rear ends of the ultrasonic vibration rods are connected to an ultrasonic generator and its high-frequency power supply instrument, and the ultrasonic generator can emit ultrasonic vibration waves to the material liquid in the material bucket.

[0016] By emitting ultrasonic waves to the material liquid in the material bucket for treatment, if the micelles in the material liquid are "washed" by ultrasonic waves, it is beneficial to the uniform dispersion of the conductive polymer and plays a role in enhancing the quality of the finished product.

[0017] Further, 3. The high-frequency power supply instrument is an instrument with an output current of 5 - 200 kHz.

[0018] Further, 4. The high-frequency power supply instrument is an instrument with an output current of 10 - 60 kHz.

[0019] Further, 5. The filtration accuracy of the filtration membrane tube of the membrane module is 0.5 nm - 100 nm, and the specific filtration accuracy can be determined according to the size of the colloid in the conductive polymer dispersion liquid.

[0020] Further, 6. The filtration membrane tube of the membrane module is made of one of the organic membrane materials such as polyamide, polyether ketone, and fluoropolymer, or one of the inorganic membrane materials such as ceramics and corrosion-resistant metals.

[0021] Further, 7. A cooling device is also provided. The cooling device adopts a multi-tube heat exchanger. The shell side of the multi-tube heat exchanger is provided with water inlets and outlets, through which cold water can enter and warm water can exit to provide cooling capacity. The inlet of the tube side of the multi-tube heat exchanger is connected to the film outlet pipeline after the regulating valve. The outlet of the tube side of the multi-tube heat exchanger is connected to the lower part of the circulation pipeline. The film outlet pipeline communicates with the circulation pipeline through the multi-tube heat exchanger.

[0022] Further, 8. A backwashing and regeneration device is also provided. The backwashing and regeneration device is composed of a backwashing tank and a backwashing sight glass. The upper end of the backwashing tank is respectively provided with a pressure conveying pipeline, a pure water pipeline and a backwashing pressure gauge. A gas release valve and an air inlet valve are connected to the pressure conveying pipeline, and a pure water valve is connected to the pure water pipeline. The lower part of the backwashing tank is connected to the backwashing sight glass. The lower outlet pipeline of the backwashing sight glass is connected to the intersection of tap water to connect to the backwashing pipeline. A backwashing valve is provided on the backwashing pipeline. The backwashing pipeline after the backwashing valve is connected to the shell side pipeline through a backwashing intersection point and then communicates with the shell side of the membrane module, so as to backwash and regenerate the filter membrane tubes of the membrane module.

[0023] With the backwashing and regeneration device, the problem of flux reduction during operation can be solved, the membrane flux can be maintained, which is beneficial to the stable operation of the system.

[0024] Further, 9. A cooling device and a backwashing and regeneration device are also provided. The cooling device adopts a multi-tube heat exchanger. The shell side of the multi-tube heat exchanger is provided with water inlets and outlets, through which cold water can enter and warm water can exit to provide cooling capacity. The inlet of the tube side of the multi-tube heat exchanger is connected to the film outlet pipeline after the regulating valve. The outlet of the tube side of the multi-tube heat exchanger is connected to the lower part of the circulation pipeline. The film outlet pipeline communicates with the circulation pipeline through the multi-tube heat exchanger.

[0025] The backwashing and regeneration device is composed of a backwashing tank and a backwashing sight glass. The upper end of the backwashing tank is respectively provided with a pressure conveying pipeline, a pure water pipeline and a backwashing pressure gauge. A gas release valve and an air inlet valve are connected to the pressure conveying pipeline, and a pure water valve is connected to the pure water pipeline. The lower part of the backwashing tank is connected to the backwashing sight glass. The lower outlet pipeline of the backwashing sight glass is connected to the intersection of tap water to connect to the backwashing pipeline. A backwashing valve is provided on the backwashing pipeline. The backwashing pipeline after the backwashing valve is connected to the shell side pipeline through a backwashing intersection point and then communicates with the shell side of the membrane module, so as to backwash and regenerate the filter membrane tubes of the membrane module.

[0026] Compared with the current technology, the technical solution of the present application has the following beneficial effects:

[0027] 1. For the membrane separation and concentration system for conductive polymer dispersion liquid, the membrane separation and concentration process is at room temperature. Compared with the evaporation concentration system, there is almost no heat loss of the conductive polymer.

[0028] 2. In the membrane separation and concentration system for conductive polymer dispersion liquid, some impurity ions can be discharged with the permeated water separated during the membrane separation process. Compared with the evaporation concentration system, the impurity ions are continuously increased during concentration, resulting in a high content of impurity ions in the finished product. However, in this membrane separation and concentration system, the content of impurity ions in the obtained finished product is low, which can improve the material properties of the conductive polymer dispersion liquid.

[0029] 3. In the membrane separation and concentration system for conductive polymer dispersion liquid, the membrane separation and concentration process is at room temperature. Compared with the evaporation concentration system, the concentrated liquid needs to be filtered, and even homogenized, with a relatively high cost. However, the finished product of membrane separation and concentration can be directly used as a product.

[0030] 4. In the solution where the ultrasonic vibration rod directly acts on the material in the pipeline before the pump in the membrane separation and concentration system for conductive polymer dispersion liquid, compared with applying ultrasound to the outer shell of the membrane module, where the vibration needs to be transmitted through the metal shell to the permeated water, then to the membrane tube, and then to the feed liquid, this solution has high efficiency. Moreover, when applying ultrasound to the outer shell of the membrane module, the vibration can only improve the partial smoothness of the membrane tube and cannot solve the difficult problem of "shearing and dispersing" the colloid of the conductive polymer dispersion liquid.

[0031] 5. The solution where the ultrasonic vibration rod directly acts on the material in the pipeline before the pump in the membrane separation and concentration system for conductive polymer dispersion liquid is simple and effective in "shearing" the colloid in the feed liquid, without the serious side effect of air resistance in the dispersion liquid caused by ultrasonic cavitation bubbles.

[0032] Generally speaking, this membrane separation and concentration system can be used for the concentration of other organic dispersion liquids with similar physical properties to conductive polymer dispersion liquid that are difficult to separate by membrane and are prone to material blockage in the membrane tube. Brief Description of the Drawings

[0033] Figure 1 It is a schematic process flow diagram of the membrane separation and concentration system for conductive polymer dispersion liquid of the present utility model.

[0034] In the figure: Equipment components: 100 material barrel, 110 material barrel cover, 200 circulation pump, 310 ultrasonic vibration rod, 320 ultrasonic generator, 330 high-frequency power supply instrument, 340 ultrasonic vibration head, 400 membrane module, 500 multi-tube heat exchanger, 600 backwash tank, 610 backwash sight glass; Pipes: 901 pipe before the pump, 902 pump outlet pipe, 903 shell-side pipe, 904 combined pipe, 905 flow pipe, 906 water outlet pipe, 907 pipe out of the membrane, 908 circulation pipe, 909 backwash pipe, 910 pressure delivery pipe, 911 pure water pipe, 912 lower outlet pipe, 913 tap water pipe; Pipe intersection points: 801 backwash intersection point, 802 throttling intersection point, 803 tap water intersection point; Valves: v1 regulating valve, v2 discharging valve, v3 flow valve, v4 water outlet valve, v5 backwash valve, v6 air release valve, v7 air inlet valve, v8 pure water valve, v9 tap water valve, v10 liquid outlet valve, v11 sampling valve; Instruments: TI01 thermometer, PI01 pump outlet pressure gauge, PI02 post-membrane pressure gauge, PI03 backwash pressure gauge, FI01 circulation flowmeter, FI02 permeate flowmeter; Materials: F raw liquid, FW permeate water, P concentrated finished product, CW cold water, CWH warm water, V permeate gas, SG compressed air, PW pure water. Valve diagrams: v1 indicates a regulating valve, v2, v3, v4, v10 indicate quick-opening butterfly valves, v5, v6, v7, v8, v9 indicate ball valves, and v11 indicates a sampling valve. Specific embodiments

[0035] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with 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, and not all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0036] Please refer to Figure 1 , a membrane separation and concentration system for a conductive polymer dispersion liquid in this embodiment, includes a material barrel 100, a material barrel cover 110, a circulation pump 200, an ultrasonic vibration rod 310, an ultrasonic generator 320, a high-frequency power supply instrument 330, an ultrasonic vibration head 340, a membrane module 400, a multi-tube cooler 500, a backwash tank 600, a backwash sight glass 610, valves, a thermometer, a flowmeter, a pressure gauge, and pipes for connection.

[0037] Among them, the circulation pump 200 is a multi-stage pump with multiple impellers, and is used for the dispersion, compression, and pressure boost of the material liquid and the bubbles therein.

[0038] An ultrasonic vibration rod 310 is provided in the pipeline 901 in front of the pump between the inlet of the circulation pump 200 and the material barrel 100. The outer end of the ultrasonic vibration rod 310 is connected to an ultrasonic generator 320 and its high-frequency power supply instrument 330. The ultrasonic generator 320 can emit main ultrasonic vibration waves to the liquid in the pipeline 901 in front of the pump, which is used to shear the colloid in the liquid.

[0039] In addition, an ultrasonic vibration rod 310 inserted into the liquid is provided on the material barrel cover 110, and three ultrasonic vibration heads 340 are provided on the outer wall of the bottom of the material barrel 100. The ultrasonic vibration heads 340 and the rear end of the ultrasonic vibration rod 310 are connected to the ultrasonic generator 320 and its high-frequency power supply instrument 330. The ultrasonic generator 320 can emit ultrasonic vibration waves to the liquid in the material barrel 100, which is used to "wash" the colloid in the liquid.

[0040] Above, the high-frequency power supply instrument 330 is an instrument with an output current of 20 - 60 kHz.

[0041] Each of the membrane modules 400 is composed of 1, 7 or 19 filter membrane tubes and a shell. The liquid to be treated flows through the tube side of the membrane module 400, and the permeated water flows out from the shell side; the filter membrane tubes of the membrane module 400 adopt ceramic membrane materials, and the filtration accuracy is 2 nm - 50 nm.

[0042] In the system, a liquid thermometer TI01 is provided on the material barrel 100. A pipeline 901 in front of the pump is provided between the outlet of the material barrel 100 and the inlet of the circulation pump 200. An outlet valve v2 is provided on the pipeline 901 in front of the pump, which can drain out the concentrated finished product P; A pipeline 902 for pumping is provided between the outlet of the circulation pump 200 and the inlet of the membrane module 400. A pressure gauge PI01 for pumping is provided on the pipeline 902 for pumping.

[0043] In the system, a sampling valve (v11) and a shell-side pipeline 903 are connected to the shell side of the membrane tube module 400. The shell-side pipeline 903 is connected to the combined pipeline 904 and the backflush pipeline 909 through the backflush intersection point 801. The backflush pipeline 909 is connected to the tap water pipeline 913 through the tap water valve v9, which can be used for flushing before and after operation; The combined pipeline 904 is connected to the flow pipeline 905 and the outlet pipeline 906 through the throttling intersection point 802. A flow valve v3 and a permeated water flowmeter FI02 are provided on the flow pipeline 905. The end of the flow pipeline 905 passes through the barrel cover 110 and extends into the material barrel 100, and when it is necessary to measure the flow rate of the permeated water, the permeated water FW can be discharged. An outlet valve v4 is provided on the outlet pipeline 906, and the permeated water FW can flow out continuously at the end of the outlet pipeline 906 during operation.

[0044] In the system, the tube-side outlet of the membrane module 400 is connected to an outlet membrane pipeline 907. A post-membrane pressure gauge PI02 and a regulating valve v1 are provided on the outlet membrane pipeline 907, and it is connected to the tube-side inlet of the multi-tube cooler 500. The shell side of the multi-tube heat exchanger 500 is provided with water inlets and outlets, through which cold water CW can enter and warm water CWH can exit to supply cooling capacity to the feed liquid; the tube-side outlet of the multi-tube cooler 500 is connected to the lower part of the circulation pipeline 908. A circulation flowmeter FI01 is installed in the upper part of the circulation pipeline 908. The upper end of the circulation pipeline 908 passes through the bucket cover 110 and extends into the bucket 100, from which cooled circulating feed liquid can exit; the lower end of the lower part of the circulation pipeline 908 is provided with a liquid outlet valve v10, through which concentrated finished product P can be discharged.

[0045] In the system, a backwashing and regeneration device is provided, which is composed of a backwashing tank 600 and a backwashing sight glass 610. A pressure delivery pipeline 910, a pure water pipeline 911 and a backwashing pressure gauge PI03 are respectively provided at the upper end of the backwashing tank 600. A gas release valve v6 and an air inlet valve v7 are connected to the pressure delivery pipeline 910, and a pure water valve v8 is connected to the pure water pipeline 911; the lower part of the backwashing tank 600 is connected to the backwashing sight glass 610. The lower outlet pipeline 912 of the backwashing sight glass 610 is connected to the upper tap water intersection point 803 to connect to the backwashing pipeline 909. A backwashing valve v5 is provided on the backwashing pipeline 909. The backwashing pipeline 909 after the backwashing valve v5 is connected to the shell-side pipeline 903 through the backwashing intersection point 801 and then connected to the shell side of the membrane module 400, so as to perform pure water backwashing and regeneration on the filter membrane tubes of the membrane module 400.

[0046] The working principle of the above embodiment is as follows:

[0047] (1) Add the raw liquid F to be concentrated into the bucket 100. Open the regulating valve v1 and start the circulation pump 200. Feed cold water CW into the shell side of the multi-tube heat exchanger 500 and discharge warm water CWH. The temperature of the feed liquid shown by the feed liquid thermometer TI01 is maintained in a cooled state. Turn on the high-frequency power supply instrument 330 to make the ultrasonic generator 320 work to drive the ultrasonic vibration rod 310 to send ultrasonic waves to the feed liquid in the pipeline 901 in front of the pump, so as to shear the colloid in the feed liquid; the high-frequency power supply instrument 330 simultaneously makes another ultrasonic generator 320 work to drive the ultrasonic vibration rod 310 inserted into the feed liquid and the ultrasonic vibration head 340 on the outer wall of the bottom of the bucket 100 to emit ultrasonic vibration waves to the feed liquid in the bucket 100, so as to "wash" the colloid in the feed liquid.

[0048] (2) The feed liquid in the bucket 100 enters the circulation pump 200 through the pipeline 901 in front of the pump. After being dispersed and pressurized by the multi-impellers of the circulation pump 200, it enters the tube side of the membrane module 400 through the pipeline 902 at the pump outlet. After being separated by the membrane module 400, it enters the multi-tube cooler 500 through the outlet membrane pipeline 907 and the regulating valve v1. After being cooled by the multi-tube cooler 500, it returns to the bucket 100 through the circulation pipeline 908 and the circulation flowmeter FI01 and passes through the bucket cover 110, and the feed liquid circulates.

[0049] (3) Adjust the regulating valve v1 to control the pressures of the pressure gauges PI01 before the pump and PI02 after the membrane within the working pressure range. Open and adjust the outlet valve v4 to collect the permeate water FW separated from the membrane module 400.

[0050] (4) During operation, when the flux decay is obvious, close the outlet valve v4, open the vent valve v6 to vent air V, open the pure water valve v8 to feed a certain amount of pure water PW into the backflush tank 600, close the vent valve v6, open the air inlet valve v7 to charge compressed air SG into the backflush tank 600, open the backflush valve v5 to backflush the membrane tubes through the shell side of the membrane module 400 with pure water via the lower port pipe 912 of the backflush sight glass 610, the backflush pipe 909, and the shell side pipe 903. Close the backflush valve v5 when air is seen in the backflush sight glass 610 to prevent gas from entering the membrane module 400.

[0051] (5) When the weight of the collected permeate water FW reaches the amount of water planned to be concentrated out from the added stock solution F, open the liquid outlet valve v10 and the discharge valve v2 to discharge the concentrated product P.

[0052] The following takes the production of concentrated conductive polymer PEDOT:PSS dispersion as an operation example to prove the technical effects of the present utility model.

[0053] Comparative example: Concentrate the PEDOT:PSS dispersion under reduced pressure at 60 °C in a 300 L jacketed reactor from a content of 0.8% to 1.6%. After cooling, discharge the product and filter the dry matter through a 60 - mesh sieve. The mesh needs to be changed multiple times, and then homogenization with a pressure above 600 bar by a homogenizer is required to ensure usability. During the process, the loss of PEDOT:PSS components is about 15%, and the sodium content in the concentrated finished product doubles compared to before.

[0054] Operation example: Using the same stock solution of PEDOT:PSS dispersion as in the comparative example, produce it with the membrane separation and concentration system of the present utility model as shown in the appendix Figure 1 The ceramic membrane is used, with a filtration accuracy of 5 nm, an ultrasonic high - frequency power supply of 40 kHz, an operating working pressure of 0.45 MPa, concentrated from a content of 0.8% to 1.9%, directly discharge the product, there is no filter residue, and it can be used directly. The loss of PEDOT:PSS components during the whole concentration process is about 2%. The sodium ion content in the concentrated finished product is basically the same as before.

[0055] From the above data, it can be seen that compared with the comparative example, when using the system of the present utility model to produce concentrated PEDOT:PSS dispersion, the loss is less and the content of impurity ions is low.

[0056] It should be noted that the structures, proportions, sizes, etc. shown in the drawings are only used to cooperate with the content disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the conditions for the implementation of the present utility model. Therefore, they do not have substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size, without affecting the effects that the present utility model can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present utility model. 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 description and are not used to limit the scope of implementation of the present utility model. The change or adjustment of their relative relationships, without substantial change in the technical content, should also be regarded as the scope of implementation of the present utility model.

[0057] It should be noted that in this text, the terms "comprising" and "including" are intended to cover non-exclusive inclusion. A process, method, article, or device including a series of elements not only includes those elements but also includes other elements not explicitly listed, or further includes elements inherent to such a process, method, article, or device.

[0058] Although the embodiments of the present utility model have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present utility model. The scope of the present utility model is defined by the appended claims and their equivalents.

Claims

1. A membrane separation and concentration system for a conductive polymer dispersion, comprising a barrel (100), a barrel cover (110), a circulation pump (200), a membrane assembly (400), a valve, a thermometer, a flow meter, a pressure gauge, and connecting pipes; The barrel (100) is provided with a feed liquid thermometer (TI01), a pump front pipeline (901) is provided between the outlet of the barrel (100) and the inlet of the circulation pump (200), a discharge valve (v2) is provided on the pump front pipeline (901), a pump outlet pipeline (902) is provided between the outlet of the circulation pump (200) and the inlet of the membrane assembly (400), a pump outlet pressure gauge (PI01) is provided on the pump outlet pipeline (902), and the membrane assembly (400) is composed of one or more filter membrane tubes and a shell, and the tube side of the membrane assembly (400) carries feed liquid and the shell side discharges permeate water (FW); The shell side of the membrane assembly (400) is connected to a sampling valve (v11) and a shell side pipeline (903); the shell side pipeline (903) is connected to a merging pipeline (904) and a backwash pipeline (909) via a backwash intersection (801); the backwash pipeline (909) is connected to a tap water valve (v9) and a tap water pipeline (913) for flushing before and after operation; the merging pipeline (904) is connected to a flow control valve (904) via a flow interception intersection (802); A pipe (905) and a water outlet pipe (906), wherein the flow pipe (905) is provided with a flow valve (v3) and a water permeation flow meter (FI02), the end of the flow pipe (905) passes through the barrel cover (110) and extends into the material barrel (100) and can discharge permeated water (FW) when metering is required, and the water outlet pipe (906) is provided with a water outlet valve (v4) and the end of the water outlet pipe (906) can always discharge permeated water (FW); The outlet of the membrane assembly (400) is connected to a film outlet pipeline (907), and a post-membrane pressure gauge (PI02) and a regulating valve (v1) are provided on the film outlet pipeline (907), and the film outlet pipeline (907) after the regulating valve (v1) is communicated with the lower part of the circulation pipeline (908), and a liquid outlet valve (v10) is provided at the lower end of the circulation pipeline (908) to discharge the concentrated finished product (P), and a circulation flow meter (FI01) is installed at the upper part of the circulation pipeline (908), and the upper end of the circulation pipeline (908) passes through the barrel cover (110) and extends into the barrel (100), so as to discharge the circulating liquid coming through the film outlet pipeline (907); it is characterized in that : a. The circulation pump (200) is a multi-stage pump having a plurality of impellers; b. An ultrasonic vibration rod (310) is arranged in the pump front pipeline (901) between the outlet of the material barrel (100) and the inlet of the circulation pump (200), and the outer end of the ultrasonic vibration rod (310) is connected to an ultrasonic generator (320) and a high-frequency power supply (330) thereof. The ultrasonic generator (320) can emit ultrasonic vibration waves to the material liquid in the pump front pipeline (901).

2. The membrane separation and concentration system according to claim 1, characterized in that : c. an ultrasonic vibration rod (310) is provided on the barrel cover (110) and is inserted into the liquid feed; and / or d. One or more ultrasonic vibration heads (340) are arranged on the outer wall of the barrel (100). The rear ends of the ultrasonic vibration heads (340) and the ultrasonic vibration rod (310) are connected to an ultrasonic generator (320) and a high-frequency power supply (330) thereof. The ultrasonic generator (320) can emit ultrasonic vibration waves to the liquid in the barrel (100).

3. The membrane separation and concentration system according to claim 1, characterized in that The high frequency power supply (330) is an instrument with an output current of 5-200kHz.

4. The membrane separation and concentration system according to claim 3, characterized in that The high frequency power supply (330) is an instrument with an output current of 10-60kHz.

5. The membrane separation and concentration system according to claim 1, characterized in that The filtration accuracy of the filtration membrane tube of the membrane assembly (400) is 0.5nm-100nm.

6. The membrane separation and concentration system according to claim 5, characterized in that The filtration membrane tube of the membrane assembly (400) is made of an organic membrane material selected from the group consisting of polyamide, polyether ketone, and fluoropolymer, or an inorganic membrane material selected from the group consisting of ceramic and corrosion-resistant metal.

7. The membrane separation and concentration system according to claim 1, characterized in that A cooling device is also provided, wherein the cooling device adopts a multi-tube heat exchanger (500), and the shell side of the multi-tube heat exchanger (500) is provided with a water inlet and a water outlet, which can take in cold water (CW) and discharge warm water (CWH) to supply cooling capacity; the inlet of the tube side of the multi-tube heat exchanger (500) is connected to the film outlet pipe (907) behind the regulating valve (v1), and the outlet of the tube side of the multi-tube heat exchanger (500) is connected to the lower part of the circulation pipe (908), and the film outlet pipe (907) is connected to the circulation pipe (908) through the multi-tube heat exchanger (500).

8. The membrane separation and concentration system according to claim 1, characterized in that A recoil regeneration device is also provided, the recoil regeneration device is composed of a recoil tank (600) and a recoil sight glass (610), the upper end of the recoil tank (600) is respectively provided with a pressure delivery pipeline (910) and a pure water pipeline (911) and a recoil pressure gauge (PI03), the pressure delivery pipeline (910) is connected to a vent valve (v6) and an air intake valve (v7), the pure water pipeline (911) is connected to a pure water valve (v8); the lower part of the recoil tank (600) is connected to A backwash mirror (610), wherein a lower pipe (912) at the lower part of the backwash mirror (610) is connected to a tap water intersection (803) and connected to a backwash pipe (909), a backwash valve (v5) is provided on the backwash pipe (909), and the backwash pipe (909) after the backwash valve (v5) is connected to a shell side pipe (903) through a backwash intersection (801) and further connected to the shell side of the membrane assembly (400), so that the filter membrane tube of the membrane assembly (400) can be backwashed and regenerated.

9. The membrane separation and concentration system according to claim 1, characterized in that : A cooling device and a recoil regeneration device are also provided, wherein the cooling device adopts a multi-tube heat exchanger (500), and the shell side of the multi-tube heat exchanger (500) is provided with a water inlet and outlet, which can take in cold water (CW) and discharge warm water (CWH) to supply cooling capacity; the inlet of the tube side of the multi-tube heat exchanger (500) is connected to the film outlet pipeline (907) behind the regulating valve (v1), and the outlet of the tube side of the multi-tube heat exchanger (500) is connected to the lower part of the circulation pipeline (908), and the film outlet pipeline (907) is connected to the circulation pipeline (908) through the multi-tube heat exchanger (500); The recoil regeneration device is composed of a recoil tank (600) and a recoil sight glass (610). The upper end of the recoil tank (600) is provided with a pressure delivery pipeline (910), a pure water pipeline (911) and a recoil pressure gauge (PI03). The pressure delivery pipeline (910) is connected to a vent valve (v6) and an air intake valve (v7). The pure water pipeline (911) is connected to a pure water valve (v8). The lower part of the recoil tank (600) is connected to the recoil sight glass (610). 10), the lower pipe (912) at the lower part of the recoil mirror (610) is connected to the tap water intersection (803) and connected to the recoil pipe (909), a recoil valve (v5) is provided on the recoil pipe (909), the recoil pipe (909) after the recoil valve (v5) is connected to the shell side pipe (903) through the recoil intersection (801) and further connected to the shell side of the membrane assembly (400), so that the filter membrane tube of the membrane assembly (400) can be recoiled and regenerated.

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