Integrated plate frame type pervaporation membrane assembly

Abstract

The invention discloses an integrated plate frame type pervaporation membrane assembly which comprises an external operation main body and a flat membrane part, the external operation main body comprises a box body, an external panel is connected to the box body in a sealed mode, and a raw material liquid inlet pipeline, a raw material liquid outlet pipeline and a vacuumizing pipeline which penetrate through the external panel from outside to inside and are communicated to the interior of the box body are arranged on the external panel; the box body is internally provided with a liquid inlet side discharge pipe and a liquid outlet side discharge pipe, the liquid inlet side discharge pipe and the liquid outlet side discharge pipe are respectively communicated with a raw material liquid inlet pipeline and a raw material liquid outlet pipeline, a plurality of outflow ports are formed along the liquid inlet side discharge pipe, a plurality of inflow ports are formed along the liquid outlet side discharge pipe, and flat sheet membrane parts are arranged between the outflow ports and the inflow ports. According to the invention, the liquid inlet side discharge pipe and the liquid outlet side discharge pipe are combined with the flat membrane part, and when the flat membrane part is provided with a plurality of membranes, the membrane arrangement density of the whole device is improved, so that the positions of the membranes are close, and the use in a space scene with a limited size is not limited and interfered.

Description

Technical Field

[0001] The invention relates to the technical field of membrane separation, and in particular to an integrated plate-and-frame pervaporation membrane assembly. Background Art

[0002] The pervaporation technology in membrane separation technology has the advantages of strong separation ability, high efficiency, low energy consumption, environmental protection and strong compatibility, and has become a research hotspot in real industrial applications. Specifically, the pervaporation technology uses the vapor pressure difference of the components on both sides of the membrane as the driving force for mass transfer, and realizes the effective separation of the mixture based on the "dissolution-diffusion" or "adsorption-separation" mechanism. In the composition of the integrated plate-and-frame pervaporation membrane assembly, the performance of the pervaporation membrane is the key factor determining the separation effect. To achieve better separation effects, structural design improvements of the integrated plate-and-frame pervaporation membrane assembly can be achieved, which can significantly improve the separation performance of the membrane and thus reduce the cost and energy consumption in the separation process. In addition, the integrated process design of pervaporation technology and various process flows can make the production and separation of the target product coherent, form a flow-type production line, improve production efficiency and reduce costs. The above-mentioned integrated process design also has the advantages of reducing pollution and sustainable production.

[0003] The structure of the integrated plate and frame pervaporation membrane assembly is the core component of the entire production line. The pervaporation process involves phase change and vacuum operation, so the membrane assembly needs to have a high degree of sealing. In addition, the structure of the integrated plate and frame pervaporation membrane assembly must provide sufficient flow space for the gas on the permeate side to facilitate gas discharge. Gas discharge helps to ensure the vacuum degree on the permeate side, thereby maintaining low resistance and pressure drop on the permeate side, which helps to improve the separation energy efficiency of the entire system. The integrated plate and frame pervaporation membrane assembly needs to be able to withstand a certain pressure and have good tolerance to organic solvents, which is the key to ensuring the stability and service life of the membrane assembly in harsh chemical environments.

[0004] At present, the integrated membrane modules used for pervaporation on the market can be mainly divided into plate-and-frame, tube-and-tube, and hollow fiber types according to their structural forms. Integrated plate-and-frame pervaporation membrane modules are widely used because of their simple manufacturing and assembly, easy maintenance and replacement, and high operating stability.

[0005] The existing integrated plate-and-frame pervaporation membrane modules still have some defects in industrial applications, including:

[0006] 1. The sealing complexity is high;

[0007] 2. Large pressure loss;

[0008] 3. The packing density of the integrated plate-and-frame pervaporation membrane module is low, and its use is limited in space scenarios with limited size. Summary of the invention

[0009] The object of the present invention is to provide an integrated plate-and-frame pervaporation membrane module in view of the problem that the integrated plate-and-frame pervaporation membrane module has a low packing density and is limited in use in space scenarios with limited size.

[0010] In order to achieve its purpose, the present invention adopts the following technical solution:

[0011] An integrated plate-and-frame pervaporation membrane module comprises: an external operating body and a flat membrane portion;

[0012] The external operation body comprises a box body, an external panel is sealedly connected to the box body, a raw material liquid inlet pipeline, a raw material liquid outlet pipeline and a vacuum pipeline are arranged on the external panel, which penetrate the external panel from the outside to the inside and are connected to the inside of the box body; a liquid inlet side discharge pipe and a liquid outlet side discharge pipe are arranged in the box body, the liquid inlet side discharge pipe and the liquid outlet side discharge pipe are respectively connected to the raw material liquid inlet pipeline and the raw material liquid outlet pipeline, a plurality of flow outlets are arranged along the liquid inlet side discharge pipe, a plurality of flow inlets are arranged along the liquid outlet side discharge pipe, and the flat membrane part is arranged between the flow outlet and the flow inlet;

[0013] The flat membrane portion includes a front clamping plate and a rear clamping plate that are positioned opposite to each other, N intermediate clamping plates are arranged between the front clamping plate and the rear clamping plate, N is an integer greater than or equal to 0, at least one diaphragm is arranged between the front clamping plate and the rear clamping plate, and when the number of diaphragms is two or more, two adjacent diaphragms are separated by the intermediate clamping plate, and the surfaces of the front clamping plate, the rear clamping plate and the intermediate clamping plate facing the diaphragm are all provided with a liquid flow channel groove and an annular sink groove, the liquid flow channel groove is located on the inner side of the sink groove, and a sealing ring is embedded in the sink groove to close the liquid flow channel groove, the The side surface of the diaphragm contacts the edge of the corresponding trough and the sealing ring, so that the space inside the trough is formed into an independent and sealed space through the whole formed by the diaphragm, the sealing ring and the trough. The front splint, the middle splint and the rear splint are each provided with a liquid inlet pipe and a liquid outlet pipe, and the liquid inlet pipe and the liquid outlet pipe are both connected to the liquid flow channel groove, the liquid inlet pipe is connected to the corresponding outflow port, and the liquid outlet pipe is connected to the corresponding inflow port. The front splint and the rear splint are clamped and connected by a connecting structure to fasten the middle splint, the diaphragm and the sealing ring.

[0014] In some preferred embodiments, the box body and the external panel are detachably connected, and an embedded structure is formed on the connecting surface of the box body and the external panel to enable the box body and the external panel to be embeddedly connected, and a sealing gasket is provided at the embedded structure to achieve vacuum sealing.

[0015] In some preferred embodiments, the liquid inlet pipe and the liquid outlet pipe are connected to the outflow port and the inflow port respectively through flexible pipes.

[0016] In some preferred embodiments, the membrane sheet includes a membrane layer and a flat support body, the flat support body is in a plate shape, and the membrane layer is synthesized on the surface of the flat support body.

[0017] In some preferred embodiments, the membrane layer is one or more of an inorganic membrane, an organic membrane and a mixed matrix membrane.

[0018] In some preferred embodiments, the membrane layer is a ZIF-8 / PMPS mixed matrix membrane.

[0019] In some preferred embodiments, the material of the flat support includes α-Al2O3.

[0020] In some preferred embodiments, the connection structure is a bolt mechanism.

[0021] In some preferred embodiments, the liquid flow channel is S-shaped.

[0022] The beneficial effects of the present invention are:

[0023] 1. By arranging the liquid inlet side pipe and the liquid outlet side pipe in combination with the flat membrane part, and when the flat membrane part is provided with multiple membrane sheets, the membrane arrangement density of the entire device is improved, so that the positions of the membranes are closely spaced, and thus the use in space scenes with limited size is not restricted or interfered, and the efficiency is higher;

[0024] 2. Through the assembly and coordination of the sealing ring and the sink, a sealed space is formed with the surface of the membrane layer to allow the liquid to flow fully on the surface of the membrane layer, with good sealing effect and simple sealing structure;

[0025] 3. The liquid flow grooves on the front, middle and rear plates are used for the flow of raw liquid and are subject to air and hydraulic pressure. At the same time, the liquid flow grooves completely cover the diaphragm to increase the force of hydraulic and air pressure in membrane separation action, greatly reducing pressure loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the decomposed structure of the external operating subject in one embodiment of the present invention.

[0027] Figure 2 It is a schematic diagram of the structure of the liquid inlet side pipe and the liquid outlet side pipe in one embodiment of the present invention.

[0028] Figure 3 Schematic diagram of the exploded structure of the flat membrane portion in one embodiment of the present invention.

[0029] Figure 4It is a schematic structural diagram of a flat membrane portion with a membrane sheet assembled in a box body in one embodiment of the present invention.

[0030] Figure 5 It is a schematic structural diagram of a flat membrane portion with three membranes assembled in a box body in one embodiment of the present invention.

[0031] Figure 6 It is a schematic diagram of the structural coordination of a single-groove sink structure and a sealing ring in one embodiment of the present invention.

[0032] Figure 7 It is a schematic diagram of the structural coordination of a double-groove sink structure and a sealing ring in one embodiment of the present invention.

[0033] Figure 8 It is a schematic diagram of the structural coordination of a double-groove sink structure and a sealing ring in another embodiment of the present invention.

[0034] Fig. 9 It is a schematic diagram of the arrangement structure of the membrane layer and the flat support body in one embodiment of the present invention.

[0035] Fig.10 It is a comparison chart of membrane separation test results at different temperatures in one embodiment of the present invention.

[0036] Fig.11 It is a comparison chart of membrane separation test results of different raw material liquid concentrations in one embodiment of the present invention.

[0037] Fig.12 It is a comparison chart of membrane separation test results under different air pressures in a box in one embodiment of the present invention.

[0038] Fig.13 It is a comparison chart of membrane separation test results of different flow rates of raw material liquid per unit time in one embodiment of the present invention.

[0039] Fig.14 It is a comparison chart of membrane separation test results under different numbers of membranes in one embodiment of the present invention.

[0040] Fig.15 It is a schematic structural diagram of diaphragms connected in series in one embodiment of the present invention.

[0041] In the attached figure:

[0042] External operating body - 100;

[0043] Box body 110; external panel 120, raw material liquid inlet pipeline 121, raw material liquid outlet pipeline 122, vacuum pipeline 123; liquid inlet side discharge pipe 130, flow outlet 131; liquid outlet side discharge pipe 140, flow inlet 141;

[0044] Flat membrane part -200;

[0045] Front clamping plate 210; rear clamping plate 220; middle clamping plate 230; diaphragm 240, membrane layer 241, flat support body 242; sealing ring 250; hose 260; liquid flow channel trough 200-a, sedimentation trough 200-b, partition 200-ba, partition space 200-bb, liquid inlet pipe 200-c, liquid outlet pipe 200-d. DETAILED DESCRIPTION

[0046] The present invention will be further described below in conjunction with embodiments, but the present invention is not limited thereto.

[0047] The experimental methods in the following examples are conventional methods unless otherwise specified.

[0048] Example 1: Integrated plate-and-frame pervaporation membrane module of the present invention

[0049] refer to Figure 1-9 As shown, an integrated plate-and-frame pervaporation membrane module includes an external operating body 100 and a flat membrane portion 200 .

[0050] The external operation body 100 includes a box body 110, and an external panel 120 is sealed and connected to the box body 110. The box body 110 is hollow, and one side is open to accommodate other components. The external panel 120 is used to close the opening of the box body 110 so that the interior of the box body 110 forms a completely sealed space.

[0051] In some preferred embodiments, a window is provided on the box 110 so that a user can view the inside of the box 110 from the outside.

[0052] In some preferred embodiments, the construction material of the box 110 includes one or more of acrylic organic glass and steel. The acrylic organic glass is transparent so that the box 110 can be viewed directly from the outside.

[0053] The external panel 120 is provided with a raw material liquid inlet pipeline 121, a raw material liquid outlet pipeline 122 and a vacuum pipeline 123 which penetrate the external panel 120 from the outside to the inside and are connected to the inside of the box. The raw material liquid inlet pipeline 121 is used to inject raw material liquid, such as n-butanol solution, from the outside. After the raw material liquid undergoes osmotic separation treatment in the box 110, it is discharged to the outside through the raw material liquid outlet pipeline 122. The vacuum pipeline 123 is used to perform a vacuum operation on the box 110 to keep it in a vacuum state.

[0054] In some preferred embodiments, the raw material liquid inlet pipeline 121, the raw material liquid outlet pipeline 122 and the vacuum pipeline 123 are all provided with connecting pipes for connecting to external devices.

[0055] In specific implementation, the raw liquid inlet pipeline 121 is connected to a circulation pump for injecting raw liquid. The raw liquid outlet pipeline 122 is connected to a hose for conveying the raw liquid after flowing through the membrane surface to the raw liquid tank. The vacuum pipeline 123 is connected to a device for condensing and collecting permeate and a vacuum pump for vacuuming is connected to the rear end. Under the action of vacuum negative pressure, membrane separation occurs.

[0056] The housing 110 is provided with a liquid inlet side discharge pipe 130 and a liquid outlet side discharge pipe 140, which are connected to the raw material liquid inlet pipeline 121 and the raw material liquid outlet pipeline 122 respectively, so that the raw material liquid is connected to the liquid inlet side discharge pipe 130 when entering from the outside, and the raw material liquid is discharged from the liquid outlet side discharge pipe 140 to the raw material liquid outlet pipeline 122 after separation. A plurality of flow outlets 131 are provided along the liquid inlet side discharge pipe 130, so that the raw material liquid can be discharged from each flow outlet 131 after entering the liquid inlet side discharge pipe 130; similarly, a plurality of inlet ports 141 are provided along the liquid outlet side discharge pipe 140, so that the raw material liquid can enter the liquid outlet side discharge pipe 140 through each inlet port 141. A flat membrane portion 200 is provided between the inlet port 131 and the inlet port 141. The raw liquid enters the flat membrane part 200 through the outflow port 131 and undergoes membrane separation. After the separation is completed, the raw liquid flows into the liquid outlet side discharge pipe 140 through the inflow port 141 .

[0057] The flat membrane part 200 includes a front clamping plate 210 and a rear clamping plate 220 that are opposite to each other. A membrane 240 is disposed between the front clamping plate 210 and the rear clamping plate 220 . The front clamping plate 210 and the rear clamping plate 220 clamp the membrane 240 in the middle to fix the membrane 240 .

[0058] N intermediate clamping plates 230 are arranged between the front clamping plate 210 and the rear clamping plate 220, where N is an integer greater than or equal to 0. At least one diaphragm 240 is arranged between the front clamping plate 210 and the rear clamping plate 220, and when the number of diaphragms 240 is two or more, two adjacent diaphragms 240 are separated by the intermediate clamping plates 230. When there is no intermediate clamping plate 230 between the front clamping plate 210 and the rear clamping plate 220, the front clamping plate 210 and the rear clamping plate 220 directly clamp the diaphragm 240. When there is an intermediate clamping plate 230, the diaphragm 240 is clamped by the cooperation between the intermediate clamping plate 230 and the front clamping plate 210 and the rear clamping plate 220, or two adjacent intermediate clamping plates 230 directly clamp the diaphragm 240.

[0059] like Figure 3As shown, the front clamping plate 210, the rear clamping plate 220 and the middle clamping plate 230 are provided with a liquid flow channel groove 200-a and an annular sink groove 200-b on the surface facing the diaphragm 240, and the liquid flow channel groove 200-a is located inside the sink groove 200-b. The sink groove 200-b is embedded with a sealing ring 250 to close the liquid flow channel groove 200-a.

[0060] The side of the diaphragm 240 contacts the edge of the corresponding sink 200-b and the sealing ring 250, so that the space inside the sink 200-b is formed into an independent and sealed space through the diaphragm 240, the sealing ring 250 and the sink 200-b. The front clamping plate 210, the middle clamping plate 230 and the rear clamping plate 220 are all provided with a liquid inlet pipe 200-c and a liquid outlet pipe 200-d, and the liquid inlet pipe 200-c and the liquid outlet pipe 200-d are both connected to the liquid flow channel 200-a. The liquid inlet pipe 200-c is connected to the corresponding flow outlet 131, and the liquid outlet pipe 200-d is connected to the corresponding flow inlet 141. The front clamping plate 210 and the rear clamping plate 220 are clamped and connected by a connecting structure to fasten the middle clamping plate 230, the diaphragm 240 and the sealing ring 250.

[0061] As described above, the external raw material liquid enters the liquid flow channel 200-a through the liquid inlet pipe 200-c, and when the front clamping plate 210, the rear clamping plate 220 and the middle clamping plate 230 are attached to clamp the membrane 240, they fully contact the side of the membrane 240 to achieve permeation and membrane separation. Between the front clamping plate 210 and the rear clamping plate 220, the front clamping plate 210 and the middle clamping plate 230, and the rear clamping plate 220 and the middle clamping plate 230 are closed, any two of the front clamping plate 210, the rear clamping plate 220 and the middle clamping plate 230 and the corresponding sealing ring 250 form a sealed space for the raw material liquid to flow.

[0062] The sealed space is located on the surface of the diaphragm 240. In a sealed state, the raw material liquid can penetrate the diaphragm 240, and the raw material liquid separated by the diaphragm 240 is in an undisturbed environment, which is more reliable and safer as a whole. In a specific implementation, the outer edge of the diaphragm 240 is close to the edge of the entire liquid flow channel 200-a.

[0063] In some preferred embodiments, under the action of external force, the front clamping plate 210, the rear clamping plate 220 and the middle clamping plate 230 are close to each other and clamped. The surface of the sealing ring 250 that contacts the diaphragm 240 is flush with the edge of the notch of the sink 200-b. The surface of the sealing ring 250 that is close to the inner side of the liquid flow channel groove 200-a is flush with the edge of the inner side of the sink 200-b that is close to the liquid flow channel groove 200-a.

[0064] In some preferred embodiments, Figure 3As shown, the liquid flow channel 200-a is S-shaped, and the overall structure of the S-shaped liquid flow channel 200-a is compact, close to the form of a full plate surface. The advantage of this structural form is that it provides a sufficiently long channel length for the raw material liquid. When the raw material liquid flows, enough raw material liquid contacts the membrane 240, thereby separating the raw material liquid more efficiently.

[0065] In some preferred embodiments, Figure 6 As shown, the sink groove 200 - b is a single groove, and the sealing ring 250 is embedded in the sink groove 200 - b which is a single groove.

[0066] In some preferred embodiments, Figure 7-8 As shown, the sink 200-b is a double groove in parallel, with a partition 200-ba formed in the middle, and the height of the partition 200-ba is lower than the height of the edges on both sides of the sink 200-b. The cross-section of the sealing ring 250 is "n" shaped to adapt to the sink 200-b with a double groove structure.

[0067] This structural form of the sink 200-b and the sealing ring 250 makes the contact area between the sealing ring 250 and the sink 200-b larger and the interaction force greater, which helps to improve the sealing effect between the sealing ring 250 and the sink 200-b. In this structural form, the surface corresponding to the "n"-shaped sealing ring 250 is completely in contact with the surface inside the sink 200-b, including the surface of the partition 200-ba. The contact between the sealing ring 250 and the sink 200-b is based on the elastic force, and the force generated between the two is large enough.

[0068] In some preferred embodiments, Figure 8 As shown, on the basis of the above-mentioned double-grooved sink 200-b and the "n"-shaped sealing ring 250, a spacing space 200-bb is formed between the bottom surface of the grooves on both sides of the sealing ring 250 and the end surface of the partition 200-ba. The function of the spacing space 200-bb is to reduce the contact area between the sealing ring 250 and the partition 200-ba, and reduce the interaction between the two, so as to facilitate and save effort to remove the sealing ring 250 from the sink 200-b; at the same time, based on the material elasticity of the sealing ring 250, when removing the sealing ring 250 from the sink 200-b, the existence of the spacing space 200-bb provides sufficient space, and by squeezing the sealing ring 250 from the outside, a gap is generated, thereby eliminating part of the force between the sealing ring 250 and the inner wall of the sink 200-b, so that the sealing ring 250 can be removed more conveniently and save effort.

[0069] In some preferred embodiments, the box body 110 and the external panel 120 are detachably connected, and an embedded structure is formed on the connection surface of the box body 110 and the external panel 120, so that the box body 110 and the external panel 120 are embedded and connected, and a sealing gasket is provided at the embedded structure to achieve vacuum sealing. In a specific implementation, the embedded structure is a mortise and tenon structure, and a mortise groove is provided on one side of the surface at the connection between the box body 110 and the external panel 120, and a protruding tenon block is provided on the other side. The connection between the box body 110 and the external panel 120 is sealed.

[0070] In some preferred embodiments, the box body 110 and the external panel 120 are detachably connected by a bolt mechanism.

[0071] The connection between the box body 110 and the external panel 120 needs to be accurately positioned to avoid the problem of misalignment. A bolt structure can be used to achieve accurate positioning through bolts and bolt holes to ensure accurate installation of each component.

[0072] To address the problem that external impact and vibration may cause damage to the box body 110 and the external panel 120 after they are connected, a bolt mechanism can be used to add spring washers to the bolts to achieve shock absorption and buffering effects, thereby preventing impact and vibration from affecting the connection structure of each component.

[0073] Regarding the connection between the box body 110 and the external panel 120, in case of large temperature difference, deformation may occur. The bolt connection can make way through threaded fitting to compensate for thermal expansion of the structural connection, thereby continuously ensuring the stability of the connection.

[0074] In some preferred embodiments, the liquid inlet pipe 200-c and the liquid outlet pipe 200-d are respectively connected to the outlet 131 and the inlet 141 through the hose 260. In a specific implementation, the two ends of the hose 260 are respectively connected to the outlet 131 and the inlet 141 to guide the raw material liquid to flow in and out, and the hose 260 can be set to be connected to the liquid inlet pipe 200-c and the liquid outlet pipe 200-d, as well as the outlet 131 and the inlet 141 in a detachable connection form.

[0075] In a specific implementation, both ends of each hose 260 can be detachably connected to the liquid inlet pipe 200-c, the liquid outlet pipe 200-d, the outflow port 131 and the inflow port 141. When necessary, the hose 260 can be removed, and then one or more of the tube 200-c, the liquid outlet pipe 200-d, the outflow port 131 and the inflow port 141 can be sealed with a plug to change the flow path of the raw liquid.

[0076] In specific implementation, both ends of each hose 260 are detachably connected to the liquid inlet pipe 200-c, the liquid outlet pipe 200-d, the flow outlet 131 and the flow inlet 141, and then in specific use, they can be connected in series or in parallel to design different flow trajectories of the raw material liquid and perform different membrane separation tests. Figure 4-5 As shown; for parallel connection, see Fig.15 As shown. In the use of parallel connection, multiple membranes 240 are connected together so that the feed flow passes through each membrane 240 at the same time, which has the beneficial effect of increasing the overall processing capacity because each membrane 240 is working at the same time. The use of parallel connection is generally used to evaluate the performance of multiple membranes 240 under the same operating conditions and to determine the optimal operating parameters. In the use of serial connection, the feed flow passes through each membrane 240 in turn. The permeate flow treated by the first membrane 240 serves as the feed for the second membrane 240, and so on. The beneficial effect of serial connection is that the separation efficiency can be improved because each subsequent membrane 240 can further concentrate the components of the permeate flow; the use of serial connection is suitable for applications that require high separation accuracy, such as in a continuous separation process, each step may require improving the purity of the component.

[0077] In practical applications, the choice of parallel connection or serial connection depends on the specific requirements of the separation process. The use of parallel connection is generally more suitable for large-scale processing and lower separation requirements, while the series configuration is suitable for situations where high purity and high separation efficiency are required.

[0078] In some preferred embodiments, Fig. 9 As shown, the membrane 240 includes a membrane layer 241 and a flat support body 242 . The flat support body 242 is in a plate shape, and the membrane layer 241 is synthesized on the surface of the flat support body 242 .

[0079] In some preferred embodiments, the membrane layer 241 is one or more of an inorganic membrane, an organic membrane, and a mixed matrix membrane. Any type of membrane layer can be used for membrane separation. When performing membrane separation treatment of a target product (e.g., alcohols), the type of membrane is selected adaptively in consideration of the material properties of the target product.

[0080] In some preferred embodiments, the membrane layer 241 is a ZIF-8 / PMPS mixed matrix membrane.

[0081] In some preferred embodiments, the material of the flat support 242 includes α-Al2O3. The advantages of α-Al2O3 are its excellent physical and chemical properties such as high temperature resistance, high hardness, wear resistance, chemical stability and electrical insulation. At the same time, the particle size distribution of α-Al2O3 is uniform and the formability is good, which helps to manufacture a support with uniform performance.

[0082] In some preferred embodiments, the connection structure is a bolt mechanism. The front clamping plate 210 and the rear clamping plate 220 are connected and fixed by the bolt structure, which is more convenient to operate.

[0083] Based on the schemes in the above embodiments, a method for membrane separation of n-butanol solution (n-butanol solution as raw material liquid) by the above integrated plate-and-frame pervaporation membrane assembly is also provided, wherein the n-butanol solution is pumped into the above module assembly through a circulation system with a circulation pump, and the above membrane assembly is vacuumed by a vacuum pump, and the specific operation thereof comprises the following steps:

[0084] S100, starting the circulation pump to stabilize the circulation system, and pumping the n-butanol solution into the integrated plate-and-frame pervaporation membrane assembly, and into the membrane according to a set path;

[0085] S200, starting the vacuum pump to evacuate the box to provide a negative pressure environment for the membrane separation process;

[0086] S300, n-butanol solution is subjected to membrane separation treatment through the membrane under the action of gas pressure and hydraulic pressure. After the substance passes through the membrane, it is discharged from the integrated plate and frame pervaporation membrane module through a set discharge path, and is condensed and collected.

[0087] In combination with the above method processing process, in a specific embodiment, the number of membrane sheets 240 is set to one, that is, a membrane layer 241 is set through a flat plate support body 242. The size of the flat plate support body 242 is 3cm×3cm. The membrane layer 241 is an organic-inorganic composite membrane prepared with ZIF-8 / PMPS as the membrane material. The mass fraction of n-butanol in the raw material liquid is 1wt.%, and the temperature of the n-butanol solution is 40°C. The raw material liquid is pumped into the integrated plate-and-frame pervaporation membrane assembly through the power provided by the circulating pump. The n-butanol raw material solution flows through the membrane surface and flows back from the outflow pipe. After the system is stable, start the vacuum pump to evacuate the system to provide the negative pressure environment required for membrane separation. After the permeation components in the raw material liquid are vaporized, they are gathered along the permeation channel of the membrane sheet 240, and after flowing out, they are condensed by the condensation device and then collected. Finally, the condensate collected in the cold trap is weighed and analyzed, such as Fig.14 As shown, the calculated flux of the component reaches 1040.11 g·m -2 ·h -1 , the separation factor reaches 30.85.

[0088] In another specific embodiment, the number of membrane sheets 240 is two. Finally, the flux of the integrated plate-and-frame pervaporation membrane module is calculated to be 942.23 g·m -2 ·h -1 , the separation factor reaches 30.75.

[0089] In yet another specific embodiment, reference Fig.14 As shown, the number of membrane sheets 240 is three. The flux of the integrated plate-and-frame pervaporation membrane module is calculated to be 825.88 g·m -2 ·h -1 , the separation factor reaches 30.27.

[0090] In another specific embodiment, the performance of the mixed matrix membrane in enriching butanol by pervaporation was tested in the temperature range of 40-80°C. The ZIF-8 / PMPS mixed matrix membrane (ZIF-8 loading of 13 wt.%) with excellent pervaporation performance in a 1 wt.% n-butanol solution at 40°C was investigated at different operating temperatures. The operating temperature was tested with a rising temperature trend. After each operating temperature test, the temperature of the water bath was adjusted until the raw material liquid temperature reached the target temperature. A 10-minute pre-pumping process was performed before testing at the target operating temperature. After the pre-pumping, the pervaporated permeate was officially collected for flux calculation and component analysis was performed using chromatography to calculate the selectivity at this operating temperature. Fig.10 As shown in the figure, the total permeation flux of the mixed matrix membrane increases significantly with the increase of the pervaporation feed liquid temperature when the operating temperature is set to 40℃, 50℃, 60℃, 70℃, and 80℃. When the temperature increases from 40℃ to 70℃, the n-butanol / H2O separation factor increases from 30.27 to 38.90; when the temperature continues to increase to 80℃, the n-butanol / H2O separation factor decreases to 36.36.

[0091] Furthermore, adjustments and comparisons were made to different concentrations of the raw liquid, and the performance of the mixed matrix membrane in enriching butanol by pervaporation was tested in the range of 1.0 to 3.0 wt.% of the raw liquid concentration, as follows: The ZIF-8 / PMPS mixed matrix membrane (ZIF-8 loading of 13 wt.%) with excellent pervaporation performance in 1 wt.% n-butanol solution at 40°C was investigated at different raw liquid concentrations, and the test was conducted with an increasing trend of raw liquid concentration. After each raw liquid concentration test, the raw liquid concentration was adjusted to the target concentration, and a 10-minute pre-pumping process was performed before testing at the target raw liquid concentration. After the pre-pumping, the pervaporated permeate was officially collected for flux calculation and component analysis was performed using chromatography to calculate the selectivity at this raw liquid concentration. Fig.11 As shown in the figure, the total permeation flux of the mixed matrix membrane increased significantly with the increase of the concentration of the pervaporation feed solution when the feed solution concentration was set to 1.0wt.%, 1.5wt.%, 2.0wt.%, 2.5wt.%, and 3.0wt.%. As the content of n-butanol in the feed solution continued to increase, the total permeation flux increased from 825.88g·m-2 ·h -1 Increased to 1233.22 g·m -2 ·h -1 , the n-butanol / H2O separation factor increased from 30.27 to 32.69.

[0092] Furthermore, the vacuum degree inside the box was adjusted and compared, and the performance of the mixed matrix membrane in pervaporation enrichment of butanol was tested in the vacuum range of 0 to 20 kPa, as follows: The ZIF-8 / PMPS mixed matrix membrane (ZIF-8 loading of 13 wt.%) with excellent pervaporation performance in 1 wt.% n-butanol solution at 40°C was investigated at different vacuum degrees. The vacuum degree was tested with an increasing trend. After each vacuum degree test, the vacuum degree was adjusted to the target vacuum degree. A 10-minute pre-pumping process was performed before testing at the target vacuum degree. After the pre-pumping, the pervaporated permeate was officially collected for flux calculation and component analysis was performed using chromatography to calculate the selectivity at this operating temperature. Fig.12 As shown in the figure, the total permeation flux and separation factor of the mixed matrix membrane decreased significantly with the decrease of vacuum degree during pervaporation when the vacuum degree was set to 0kPa, 5kPa, 10kPa, and 20kPa. When the pressure in the vacuum box increased from 0kPa to 20kPa, the total permeation flux increased from 825.88g·m -2 ·h -1 Reduced to 20.88 g·m -2 ·h -1 , the n-butanol / H2O separation factor decreased from 30.27 to 10.08.

[0093] Furthermore, the flow rate range of the raw material liquid was adjusted and compared, and the flow rate of 1.0-2.0 Lmin -1 The performance of the mixed matrix membrane in enriching butanol by pervaporation was tested within a flow range. The ZIF-8 / PMPS mixed matrix membrane (ZIF-8 loading of 13 wt.%) with excellent pervaporation performance in 1 wt.% n-butanol solution at 40°C was investigated at different feed liquid flow rates. The feed liquid flow rate was tested with an upward trend. After each flow test, the flow rate was adjusted to the target flow rate. A 10-minute pre-pumping process was performed before testing at the target flow rate. After the pre-pumping, the permeate from the pervaporation was officially collected for flux calculation and component analysis using chromatography to calculate the selectivity at this operating temperature. Fig.13 As shown, the raw material liquid flow rate is set to 1.0Lmin -1 、1.3Lmin -1 、1.5Lmin -1 、1.7Lmin -1 、2.0L min-1 The total permeation flux and separation factor of the mixed matrix membrane did not change much with the increase of the feed liquid flow rate during the pervaporation process. -1 Increase to 2.0Lmin -1 When the total permeation flux is 776.17 g·m -2 ·h -1 to 825.88 g·m -2 ·h -1 The n-butanol / H2O separation factor fluctuates in the range of 28.09 to 30.27.

[0094] Furthermore, the performance of the mixed matrix membrane in pervaporation enrichment of butanol within the range of 1 to 3 membranes was tested. Specifically, the ZIF-8 / PMPS mixed matrix membrane (ZIF-8 loading of 13 wt.%) with excellent pervaporation performance in 1 wt.% n-butanol solution at 40°C was used to investigate the pervaporation performance of different membrane numbers using an integrated plate-and-frame membrane assembly. A 10-minute pre-pumping process was performed before testing at the target membrane number. After the pre-pumping, the permeate from the pervaporation was officially collected for flux calculation and component analysis using chromatography to calculate the selectivity at this operating temperature. Fig.14 As shown in the above test process, the number of tested membranes was set to 1, 2, and 3. The total permeation flux of the mixed matrix membrane tested with the integrated flat membrane section decreased slightly with the increase of the number of membranes, from 1040.11 g·m -2 ·h -1 Down to 825.88 g·m -2 ·h -1 , the separation factor remains stable.

[0095] Example 2: Preparation method of ZIF-8 / PMPS mixed matrix membrane

[0096] The preparation method of the ZIF-8 / PMPS mixed matrix membrane sheet in Example 1 is carried out according to the following steps:

[0097] S1. Preparation of Solution A:

[0098] 0.75 g ZIF-8 was added to 14.25 g isooctane (CAS No.: 540-84-1) to prepare a ZIF-8 dispersion. 0.5 g crosslinking agent TEOS (tetraethyl orthosilicate, CAS No.: 562-90-3) and 5.75 g isooctane were added to the ZIF-8 dispersion and mixed by probe ultrasonic in an ice-water bath under the ultrasonic conditions of 60% probe ultrasonic amplitude and 5 min; then magnetic stirring was performed under the conditions of 600 rpm and 1 h to obtain liquid A.

[0099] S2. Preparation of Solution B:

[0100] Take 5 g of organic PMPS (polymethylphenylsiloxane, CAS No.: 9004-73-3) and add it to 20 g of isooctane. Mix well under magnetic stirring at a stirring speed of 600 rpm for 1 h to obtain liquid B.

[0101] S3. Preparation of casting solution

[0102] Pour liquid A into liquid B, and mix the mixed solution by probe ultrasonic mixing in an ice-water bath. The ultrasonic conditions are: probe ultrasonic amplitude: 60%, ultrasonic time: 5min, and then magnetic stirring. The magnetic stirring conditions are: speed: 600rpm, stirring time: 1h. Then add the catalyst DBTDL (dibutyltin dilaurate, CAS No.: 77-58-7) and stir evenly (magnetic stirring conditions are: speed: 400rpm, stirring time: 10s) to form a uniform and stable casting liquid. The mass ratio of catalyst / crosslinking agent / PMPS / ZIF-8 / isooctane in the casting liquid is: 1:10:100:15:800. That is, the ZIF-8 loading is 13.0wt.%, and the ZIF-8 loading = the mass of ZIF-8 / (the sum of the mass of ZIF-8+PMPS).

[0103] S4. Preparation of mixed matrix membrane

[0104] Pour the casting liquid into the casting liquid tank, fix the fully cleaned and dried α-Al2O3 flat plate support (thickness 6mm) to the automatic lifting machine through the membrane assembly, and adjust the speed of the support body immersing in the casting liquid (viscosity 40cP~50cP) to 180mm min -1 The residence time is 10s, and then the support is pulled out from the casting liquid at a pulling speed of 60mm min -1 The support with the casting liquid adhered to the surface was placed at room temperature of 25°C to dry for 24 hours, then placed in a forced air drying oven at 100°C for 12 hours, and finally placed in a vacuum drying oven at 100°C for 12 hours to obtain a ZIF-8 / PMPS mixed matrix membrane sheet with stable performance, the membrane sheet comprising a flat support and a membrane layer synthesized on the surface of the flat support, the membrane layer being the ZIF-8 / PMPS mixed matrix membrane.

Claims

1. An integrated plate-and-frame pervaporation membrane module, characterized in that: include: An external operating body (100) and a flat membrane portion (200); The external operation body (100) comprises a box body (110), to which an external panel (120) is sealed and connected, and the external panel (120) is provided with a raw material liquid inlet pipeline (121), a raw material liquid outlet pipeline (122) and a vacuum pipeline (123) which penetrate the external panel (120) from the outside to the inside and are connected to the inside of the box body; the box body (110) is provided with a liquid inlet side discharge pipe (130) and a liquid outlet side discharge pipe (131). The liquid inlet side discharge pipe (130) and the liquid outlet side discharge pipe (140) are respectively connected to the raw material liquid inlet pipeline (121) and the raw material liquid outlet pipeline (122); a plurality of flow outlets (131) are arranged along the liquid inlet side discharge pipe (130); a plurality of flow inlets (141) are arranged along the liquid outlet side discharge pipe (140); and the flat membrane portion (200) is arranged between the flow outlets (131) and the flow inlets (141); The flat membrane portion (200) comprises a front clamping plate (210) and a rear clamping plate (220) which are located opposite to each other, N intermediate clamping plates (230) are arranged between the front clamping plate (210) and the rear clamping plate (220), N is an integer greater than or equal to 0, at least one membrane sheet (240) is arranged between the front clamping plate (210) and the rear clamping plate (220), and when the number of the membrane sheets (240) is two or more, two adjacent membrane sheets (240) are connected by the intermediate clamping plates. The front clamping plate (210), the rear clamping plate (220) and the middle clamping plate (230) are separated from each other by a plate (230), and the surfaces of the front clamping plate (210), the rear clamping plate (220) and the middle clamping plate (230) facing the diaphragm (240) are all provided with a liquid flow channel groove (200-a) and an annular sink groove (200-b), wherein the liquid flow channel groove (200-a) is located on the inner side of the sink groove (200-b), and a sealing ring (250) is embedded in the sink groove (200-b) to seal the liquid flow channel groove (200-a). The diaphragm (240) ) is in contact with the edge of the corresponding sink (200-b) and the sealing ring (250), so that the space inside the sink (200-b) is formed into an independent and sealed space through the whole formed by the diaphragm (240), the sealing ring (250) and the sink (200-b), and the front clamping plate (210), the middle clamping plate (230) and the rear clamping plate (220) are all provided with a liquid inlet pipe (200-c) and a liquid outlet pipe (200-d), and the The liquid inlet pipe (200-c) and the liquid outlet pipe (200-d) are both connected to the liquid flow channel (200-a), the liquid inlet pipe (200-c) is connected to the corresponding outflow port (131), and the liquid outlet pipe (200-d) is connected to the corresponding inflow port (141), and the front clamping plate (210) and the rear clamping plate (220) are clamped and connected by a connecting structure to fasten the middle clamping plate (230), the diaphragm (240) and the sealing ring (250).

2. The integrated plate-and-frame pervaporation membrane module according to claim 1, characterized in that: Also includes: The box body (110) and the external panel (120) are detachably connected, and an embedded structure is formed on the connection surface of the box body (110) and the external panel (120) so that the box body (110) and the external panel (120) are embeddedly connected, and a sealing gasket is provided at the embedded structure to achieve vacuum sealing.

3. The integrated plate-and-frame pervaporation membrane module according to claim 1, characterized in that: Also includes: The liquid inlet pipe (200-c) and the liquid outlet pipe (200-d) are respectively connected to the outflow port (131) and the inflow port (141) through a hose (260).

4. The integrated plate-and-frame pervaporation membrane module according to claim 1, characterized in that: Also includes: The membrane sheet (240) comprises a membrane layer (241) and a flat plate support body (242), the flat plate support body (242) is in a plate shape, and the membrane layer (241) is synthesized on the surface of the flat plate support body (242).

5. The integrated plate-and-frame pervaporation membrane module according to claim 4, characterized in that: Also includes: The film layer (241) is one or more of an inorganic film, an organic film and a mixed matrix film.

6. The integrated plate-and-frame pervaporation membrane module according to claim 5, characterized in that: Also includes: The membrane layer (241) is a ZIF-8 / PMPS mixed matrix membrane.

7. The integrated plate-and-frame pervaporation membrane module according to claim 4, characterized in that: Also includes: The material of the flat plate support (242) includes α-Al2O3.

8. The integrated plate-and-frame pervaporation membrane module according to claim 1, characterized in that: Also includes: The connecting structure is a bolt mechanism.

9. The integrated plate-and-frame pervaporation membrane module according to claim 1, characterized in that: Also includes: The liquid flow channel (200-a) is S-shaped.

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