CN114062219B - Breathable film performance test integrated device and operation method thereof - Google Patents

Abstract

The invention relates to the technical field of separation membrane testing, and proposes an integrated device for testing the performance of breathable membranes and an operating method thereof. The device includes: a component testing module, a pressure driving control module connected to a pipeline of the component testing module, and a pressure control module connected to the component testing module. The gas flow detection module and the control system are respectively connected with the component test module, the pressure drive control module and the gas flow detection module. The component test module includes: an upper unit, a middle unit and a lower unit that are sealed and connected, and the upper unit and the pressure drive module Connected through pipelines; the middle unit has through holes and non-through holes from bottom to top. The bottom end of the through hole can be detachably connected to the quick-twist joint. The bottom end of the quick-twist joint can be detachably connected to the membrane module. The bottom end of the non-through hole can be detachably connected. Support rod. Through the technical solution of the present invention, comprehensive evaluation and quantitative evaluation of the burst pressure, membrane air permeability coefficient and integrity within the membrane can be achieved in the same device. Moreover, the test accuracy is higher and the test efficiency is higher.

Description

An integrated device for testing breathable membrane performance and its operation method

Technical field

The invention relates to the technical field of separation membrane testing, and specifically relates to an integrated device for testing the performance of a breathable membrane and an operating method for an integrated device for testing the performance of a breathable membrane.

Background technique

As an important branch of the separation membrane field, breathable membranes are widely used in food, medicine, biology, environmental protection, chemical industry, water treatment and other fields. The performance of a separation membrane is the core that determines its use. At present, the key parameters of breathable membrane performance mainly include air permeability coefficient, separation coefficient, mechanical strength, integrity, etc. At present, water permeability testing equipment is generally used to detect the integrity of microporous breathable membranes. For the detection of gas permeability of breathable membranes, due to the relatively simple testing equipment, it is impossible to efficiently and accurately test the gas permeability and separation coefficient of separation membranes; in addition, for The test of mechanical strength, especially the internal and external burst pressure, generally uses water flow from the inside to pressurize the membrane to rupture and monitor the burst pressure. The data obtained by this method has a certain delay effect, that is, if the separation membrane already has certain defects before it completely ruptures, this method It cannot provide accurate real-time feedback and is generally suitable for rough testing of bursting pressure.

In related technology, CN103063523A discloses a device and method for testing the burst pressure and compressive pressure of hollow fiber membranes. The burst pressure is determined by recording the pressure changes during the entire test process. However, the test accuracy is low. Moreover, it is difficult to achieve quantitative testing of multiple properties such as gas separation membrane air permeability by only performing a single test on burst pressure and compressive pressure. Although CN102798586A discloses a new test system for testing the air permeability of micro-permeable membranes, using The liquid level meter is a rising tube liquid level gauge. It uses isobaric liquid to fill the original space after gas permeation. By recording the liquid entry speed, it can measure the rate of gas passing through the micro-permeable membrane under a certain pressure difference. The test is more cumbersome and less accurate. Poor, and it is also difficult to achieve quantitative testing of multiple properties such as bursting pressure and integrity of breathable membranes.

Therefore, there is an urgent need to develop a new breathable membrane performance testing device to solve the current problems of lack of performance evaluation methods for breathable membranes, single equipment test indicators, and low integration.

Contents of the invention

In view of this, it is necessary to provide an integrated device and operation method for breathable membrane performance testing to address the above problems. In the same device, not only the burst pressure within the membrane can be quickly and accurately tested, but also the membrane’s air permeability coefficient, The comprehensive evaluation of integrity can realize the quantitative evaluation of multiple properties of the breathable separation membrane. Moreover, the test accuracy is high and the test efficiency is high.

In order to achieve the above objects, the present invention adopts the following technical solutions:

An integrated device for testing breathable membrane performance, including: a component testing module, a pressure control module connected to the top pipeline of the component testing module, a gas flow detection module connected to the bottom of the component testing module, respectively. A control system that is communicatively connected to the component testing module, the pressure control module and the gas flow detection module. The component testing module includes:

The upper unit, the middle unit and the lower unit are sealed and connected in sequence from top to bottom. The upper unit is connected to the pressure drive module through pipelines; the middle unit has through holes and non-through holes from bottom to top. The bottom end of the through hole can be detachably connected to the quick-twist joint, the bottom end of the quick-twist joint can be detachably connected to the membrane component, and the bottom end of the non-through hole can be detachably connected to the support rod.

Preferably, the upper unit includes: an upper cylinder; an air inlet provided on the top surface of the upper cylinder, connected to the pressure drive module through a pipeline; and a first row of air inlets provided on the side of the upper cylinder. air port, a first solenoid valve is provided on the exhaust pipeline connected to the first exhaust port; an air intake side pressure sensor is connected to the side of the upper cylinder, and the air intake side pressure sensor is located on the upper The height of the connection position on the cylinder is higher than the height of the first exhaust port, and the intake side pressure sensor is communicatively connected with the control system.

Preferably, the lower unit includes: a lower cylinder; a second exhaust port provided on the side of the lower cylinder, the second exhaust port is connected to the gas flow detection module in a pipeline, and is connected to the third exhaust port. A second solenoid valve is provided on the exhaust pipeline connected to the two exhaust ports; a gas transmission side pressure sensor is connected to the side of the lower cylinder, and the connection of the gas transmission side pressure sensor on the lower cylinder is The height of the position is higher than the height of the second exhaust port, and the gas transmission side pressure sensor is communicatively connected with the control system.

Preferably, the upper unit, the middle unit, and the lower unit are sealingly connected through threads and sealing rings, and the upper and lower ends of the middle unit are respectively inserted into the interior of the upper unit and the lower unit;

The through holes and non-through holes opened on the middle unit are distributed in a cross shape like a cross. There are two through holes and two non-through holes. The through holes are one-to-one with the quick-twist joint. The non-through hole and the connecting rod are arranged one-to-one.

Preferably, the support rod is a telescopically adjustable support rod, and the length adjustment range of the telescopically adjustable support rod is 5cm-15cm; the gas flow detection module is a high-precision gas flowmeter, and the high-precision gas flowmeter The measuring range is 0-100ml/min.

Preferably, the pressure control module includes: a plurality of high-pressure gas bottles arranged in parallel, which are respectively connected to the component test module pipeline, and a pressure reducing valve is provided on the air outlet connection pipeline of each high-pressure gas bottle. , an electrical proportional regulating valve is installed on the connecting pipeline close to the component test module.

An operation method of the integrated breathable membrane performance testing device as described above includes the following steps:

Install both ends of the membrane module on the quick-twist joints of the middle unit of the module test module, adjust the height of the support rod, and straighten the separation membrane downward to make it evenly distributed;

Tighten the sealing connection between the middle unit, the upper unit and the lower unit, and connect the component test module to the pressure drive control module, the intake side pressure sensor, the exhaust side pressure sensor, and the exhaust pipeline in sequence;

Start the control system. When the control system operates normally, open the designated high-pressure gas cylinder and its pressure reducing valve to adjust the test pressure;

In the constant pressure mode, set the pre-check pressure, voltage boost time, and voltage stabilization time, open the first solenoid valve connected to the upper unit of the component test module, and the second solenoid valve connected to the lower unit of the component test module, and control Increase the pressure, fully discharge the air in the device, and then close the first solenoid valve;

After the pressure is stabilized, monitor the permeate side pressure through the gas permeate side pressure sensor. If the monitored permeate side pressure remains within the specified pressure range for the specified time, it is determined that the membrane module is intact and there is no problem with the air tightness of the device. ;

After the pressure of the control device is released, conduct the air permeability coefficient test or membrane module integrity test or internal explosion pressure test or conduct the air permeability coefficient test and membrane module integrity test in sequence or conduct the air permeability coefficient test and internal explosion pressure test in sequence or conduct the membrane module integrity test in sequence performance test and internal burst pressure test or conduct air permeability coefficient test, membrane module integrity test and internal burst pressure test in sequence;

When the test is completed, control saves data, resets pressure, removes components, and turns off power.

Preferably, the air permeability coefficient test includes the following steps:

In the constant pressure mode, set the test pressure, voltage boost time, and voltage stabilization test time to control the startup of voltage boost. The value range of the test pressure is 0.1MPa-0.3MPa, and the value range of the voltage boost time is is 5min-10min, and the voltage stabilization test time is not less than 30min;

When the pressure is constant, the gas flow detection module detects the permeated gas flow in real time;

According to the permeated gas flow rate, the air permeability coefficient is calculated according to a preset formula, wherein the preset formula is:

F=Q/(ΔP·S),

Among them, F is characterized by the air permeability coefficient (mL·cm ^-2 ·min ^-1 ·bar ^-1 ), Q is characterized by the permeated gas flow rate (ml/min), and ΔP is characterized by the transmembrane pressure difference (bar), that is, the setting Test pressure; S is characterized by the effective area of the membrane (cm ² ).

Preferably, the membrane module integrity test includes the following steps:

In the constant pressure mode, set the test pressure, pressure increase time, and voltage stabilization test time, and control the use of a nitrogen high-pressure cylinder to start the pressure increase, where the value range of the test pressure is 0.1MPa-0.3MPa, and the pressure increase The value range of the time is 5min-10min, and the voltage stabilization test time is not less than 30min;

When the pressure is constant, the gas flow detection module detects the nitrogen gas flow in real time;

After the control device releases pressure, in the same constant pressure mode, the control uses an oxygen high-pressure cylinder to start the pressure increase. When the pressure becomes constant, the gas flow detection module detects the flow of oxygen gas in real time;

After the control device releases pressure, in the same constant pressure mode, the control uses a high-pressure carbon dioxide gas cylinder to start the pressure increase. When the pressure becomes constant, the flow of carbon dioxide gas is detected in real time through the gas flow detection module;

Calculate the ratio between any two of the nitrogen gas flow rate, the oxygen gas flow rate, and the carbon dioxide gas flow rate, and the ratio is determined by the larger value compared to the smaller value;

If any ratio is much greater than 1, the integrity of the membrane module is determined to be good;

If there is a ratio approaching 1, it is determined that there is a problem with the integrity of the membrane module.

Preferably, the internal burst pressure test includes the following steps:

In boost mode, set the maximum test pressure, boost time, and control the startup boost;

During the pressure boosting process, the gas flow detection module detects the permeated gas flow in real time, and the inlet side pressure sensor detects the test pressure in real time to generate a test pressure-permeated gas flow relationship curve;

If the increase value of the permeated gas flow rate per unit time is greater than the preset value, it is determined that the membrane is ruptured, the pressure increase is stopped, and the maximum test pressure corresponding to the permeated gas flow rate per unit time is determined to be the burst pressure within the membrane.

The beneficial effects of the present invention are:

(1) An integrated device for testing the performance of breathable membranes proposed by the present invention can not only quickly and accurately test the burst pressure in the membrane, but also comprehensively evaluate the breathable performance and integrity of the membrane, realizing a true one-machine Multipurpose.

(2) The integrated device for testing breathable membrane performance proposed by the present invention has a simple structure and is easy to use. It can be suitable for related performance testing of PMP membranes, PP separation membranes, PVDF hydrophobic membranes, etc., and the testing method is simple and easy to operate. The test structure is stable and reliable with high reproducibility.

(3) The invention proposes an integrated device for testing the performance of breathable membranes, which is equipped with a control system and communication connections with each module. It has a real-time online monitoring function of numerical values, timely data feedback, and high measurement accuracy.

(4) An integrated device for testing breathable membrane performance proposed by the present invention is provided with a component test module. The component test module includes an upper unit, a middle unit and a lower unit that are sealed and connected in sequence from top to bottom, and the membrane module is detachably connected in the middle On the unit, it is more convenient to disassemble and replace the membrane module. At the same time, the middle unit is equipped with a support rod to fix the membrane module and straighten the membrane filaments on the membrane module as much as possible to make them evenly arranged to ensure measurement accuracy and ensure Conducive to quantitative comparison.

(5) The operation method of an integrated device for testing breathable membrane performance proposed by the present invention realizes the test of air permeability coefficient, membrane component integrity test, and internal explosion pressure test, and realizes the quantification of performance tests, making it easier to comprehensively evaluate Membrane performance.

Additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of the drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

Figure 1 shows a schematic structural diagram of an integrated device for testing breathable membrane performance according to an embodiment of the present invention;

Figure 2 shows a schematic top structural view of the middle unit of the component testing module in an integrated device for testing breathable membrane performance according to an embodiment of the present invention;

Figure 3 shows a schematic structural diagram of the installation position of the membrane module after the membrane module is installed in the component testing module of an integrated device for testing breathable membrane performance according to an embodiment of the present invention;

Figure 4 shows a schematic structural diagram of a membrane module according to an embodiment of the present invention.

Among them, the corresponding relationship between the reference numbers and components in Figures 1 to 4 is:

10 component test module, 102 upper unit, 1022 upper cylinder, 1024 air inlet, 1026 first exhaust port, 1028 first solenoid valve, 1030 air inlet side pressure sensor, 104 middle unit, 1042 through hole, 1044 non-through hole hole, 1046 quick-twist joint, 1048 support rod, 106 lower unit, 1062 lower cylinder, 1064 second exhaust port, 1066 second solenoid valve, 1068 gas transmission side pressure sensor, 108 sealing ring, 20 pressure control module , 202 high-pressure gas cylinders, 204 pressure reducing valves, 206 electrical proportional control valves, 30 gas flow monitoring modules, 40 control systems, 50 membrane components, 502 membrane filaments.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clear, the technical solutions of the present invention will be further clearly and completely described below in conjunction with the embodiments of the present invention. It should be noted that the described embodiments are only some of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

As shown in Figures 1 to 4, an integrated device for testing breathable membrane performance according to an embodiment of the present invention includes: a pressure driving control module 20, a component testing module 10, a gas flow detection module, a control system 40, and a component testing module The top of the module 10 is connected to the pipeline of the pressure drive module, the bottom of the component test module 10 is connected to the pipeline of the gas flow detection module, and the control system 40 is connected to the component test module 10, the pressure drive module and the gas flow detection module. The component testing module 10 includes: an upper unit 102, a middle unit 104 and a lower unit 106 that are sealed and connected in sequence from top to bottom. The upper unit 102 is connected to the pressure drive module through pipelines. The middle unit 104 has through holes 1042 and 1042 from bottom to top. The bottom end of the non-through hole 1044 and the through hole 1042 can be detachably connected to the quick-twist connector 1046, the bottom end of the quick-twist connector 1046 can be detachably connected to the membrane assembly 50, and the bottom end of the non-through hole 1044 can be detachably connected to the support rod 1048. Install the membrane module 50 under the middle unit 104 through the quick-twist joint 1046, and straighten the membrane wires 502 on the membrane module 50 through the support rod 1048 to make them evenly arranged for testing. The structure of the membrane module 50 is shown in Figure 4 As shown in the figure, the membrane fiber 502 is sealed with a PU tube with a diameter of 10 mm or 8 mm and epoxy glue, and then the end face is cut off to expose the end hole of the membrane fiber to form the membrane module 50. The cross-section is cut to leave a through hole 1042 for connection with the quick-twist joint 1046. Air intake and plug-in design make it easy to replace the test components. After that, the middle unit 104 is sealed with the upper unit 102 and the lower unit 106 to realize the assembly of the component test module 10. It is more convenient to disassemble and replace the membrane module 50, and it is supported by The rod 1048 straightens the membrane wires 502 on the membrane module 50 as much as possible so that they are evenly arranged to ensure measurement accuracy and facilitate quantitative comparison. The pressure drive and precise regulation of pressure are realized through the pressure drive control module 20 to provide pressure for the component testing module 10. The gas flow detection module is a high-precision gas flow meter. The measuring range of the high-precision gas flow meter is 0-100ml/min. Under the control of various modes and parameters, the gas flow detection module is used to detect the permeated gas flow rate and accurately measure the gas flow rate on the permeable side. This provides data support for the performance testing of each breathable membrane and is conducive to the realization of multiple applications in the same device. Quantitative testing of membrane performance. The control system 40 is used to control the operation of the entire device and implement functions such as pressure, test time setting, and real-time curve monitoring. It can be set to constant pressure mode and boost mode. The constant pressure mode is used for pre-inspection, permeability coefficient testing, and integrity testing. , boost mode is used for internal burst pressure testing.

In addition, the membrane module 50 may also be a flat breathable membrane that is directly sealed and connected between the upper unit 102 and the lower unit 106 .

Further, as shown in FIG. 1 , the upper unit 102 includes an upper cylinder 1022, an air inlet 1024, a first exhaust port 1026, a first solenoid valve 1026, an air intake side pressure sensor 1030, and the like. The air inlet 1024 is provided on the top surface of the upper cylinder 1022 and is connected to the pressure driving module through a pipeline. The pressure driving module inputs gas to the component testing module 10 through the air inlet 1024 to provide pressure. The first exhaust port 1026 is provided on the side of the upper cylinder 1022, and the exhaust pipeline connected to it is provided with a first solenoid valve 1026, which is opened for exhaust when the air in the device is eliminated and the pressure is relieved. The exhaust pipeline can It is connected to the external gas collection and processing device to classify and process different gases. The intake side pressure sensor 1030 is connected to the side of the upper cylinder 1022, and the connection position on the upper cylinder 1022 is higher than the height of the first exhaust port 1026. The intake side pressure sensor 1030 is communicatively connected with the control system 40. It is used to detect the incoming pressure and adjust the incoming pressure of the control system 40 so that it can reach the set test pressure.

In addition, a temperature sensor can also be connected to the top surface of the upper cylinder 1022, and the temperature sensor is communicatively connected with the control system 40 to provide temperature data of the gas inside the upper cylinder 1022.

Further, as shown in FIG. 1 , the lower unit 106 includes: a lower cylinder 1062 , a second exhaust port 1064 , a second solenoid valve 1066 , and a gas permeation side pressure sensor 1068 . The second exhaust port 1064 is provided on the side of the lower cylinder 1062. The second exhaust port 1064 is connected to the gas flow detection module pipeline. A second solenoid valve 1066 is provided on the exhaust pipeline connected to the second exhaust port 1064. During the test It is generally in a normally open state during the process, and is closed when the test is completely completed, which facilitates the gas flow monitoring module 30 to detect the transmitted gas flow, and also plays a certain protective role for the gas flow monitoring module 30 . The gas transmission side pressure sensor 1068 is connected to the side of the lower cylinder 1062, and the connection position on the lower cylinder 1062 is higher than the height of the second exhaust port 1064. The gas transmission side pressure sensor 1068 is communicatively connected with the control system 40. It is used to monitor the permeate side pressure and perform pre-inspection at the initial stage of operation of the device to initially determine whether the membrane module 50 is intact and whether there is no problem with the air tightness of the device, so that more accurate data can be obtained during later testing and unnecessary testing can be avoided. Mistakes.

Further, as shown in Figures 1 and 2, the upper unit 102, the middle unit 104, and the lower unit 106 are sealingly connected through threads and sealing rings 108, and the upper and lower ends of the middle unit 104 are respectively inserted into the upper unit 102 and the lower unit 106. The interior, on the one hand, is easy to disassemble and, on the other hand, has good sealing, ensuring the airtightness of the device. The middle unit 104 is provided with through holes 1042 and non-through holes 1044 arranged in a "cross" shape. There are two through holes 1042 and two non-through holes 1044 . The through holes 1042 are one-to-one with the quick-twist connector 1046 Setting, the non-through hole 1044 and the connecting rod are set one-to-one, which further ensures the stability of the installation and fixation of the membrane module 50 and further ensures the smooth progress of the test.

Specifically, the through hole 1042 may be an internally threaded through hole 1042 , and the non-through hole 1044 may be an internally threaded non-through hole 1044 .

Further, the support rod 1048 is a telescopically adjustable support rod 1048. The length adjustment range of the telescopically adjustable support rod 1048 is 5cm-15cm, and can be adapted to various types of membrane modules 50. As shown in Figure 3, the support rod 1048 moves the membrane The membrane wires 502 in the assembly 50 are straightened downward to make them evenly arranged to facilitate better testing.

Further, as shown in FIG. 1 , the pressure control module 20 includes: multiple high-pressure gas bottles 202 arranged in parallel, which are respectively connected to the pipeline of the component test module 10 . For example, three high-pressure gas bottles 202 can be provided, each of which has Bottles 202 are respectively filled with nitrogen, oxygen, and carbon dioxide. A pressure reducing valve 204 is provided on the outlet connection pipeline of each high-pressure gas bottle 202 for controlling the outflow of gas. An electrical circuit is provided on the connection pipeline close to the component test module 10. The proportional regulating valve 206 is used to accurately adjust the gas pressure, so as to provide accurate gas pressure for the component testing module 10 under the control of the control system 40 .

The operation method of the integrated breathable membrane performance testing device according to the embodiment of the present invention includes the following steps:

S1, install both ends of the packaged membrane module on the module test module respectively. Install both ends of the membrane module on the quick-twist joints of the middle unit of the module test module. Adjust the height of the support rod and straighten the separation membrane downward to make it uniform. distributed;

S2, tighten the sealing connection between the middle unit, the upper unit, and the lower unit, and connect the component test module to the pressure drive control module, the intake side pressure sensor, the exhaust side pressure sensor, and the exhaust pipeline in sequence;

S3, start the control system. When the control system operates normally, open the designated high-pressure gas cylinder and its pressure reducing valve to adjust the test pressure;

S4, in constant pressure mode, set the pre-check pressure, voltage boost time, and voltage stabilization time, open the first solenoid valve connected to the upper unit of the component test module, and the second solenoid valve connected to the lower unit of the component test module to control the voltage boost. , fully discharge the air in the device, and then close the first solenoid valve;

S5, after the pressure is stabilized, monitor the permeate side pressure through the gas permeate side pressure sensor. If the permeate side pressure is monitored to remain within the specified pressure range for the specified period of time, it is determined that the membrane module is intact and there is no problem with the air tightness of the device;

Specifically, for example, if the specified time is 5 minutes and the specified pressure range is 0-3Kpa, which is close to 0, the second solenoid valve is open, and the gas does not hold pressure on the lower side and flows out directly after being detected by the gas flow meter. That is, after the pressure is stabilized, if the monitored permeate side pressure approaches 0 or fluctuates within a small pressure range for 5 minutes, it is considered that the membrane module is intact and the air tightness of the device is no problem.

S6. After the control device releases pressure, switch to the constant pressure mode, set the test pressure, pressure increase time, and voltage stabilization test time, control the startup pressure increase, and perform a breathability coefficient test. The test pressure range is 0.1MPa-0.3 MPa, the value range of the voltage boost time is 5min-10min, and the voltage stabilization test time is not less than 30min;

S7, when the pressure is constant, the gas flow detection module detects the permeated gas flow in real time;

According to the permeable gas flow rate, the air permeability coefficient is calculated according to the preset formula, where the preset formula is:

F=Q/(ΔP·S),

Among them, F is characterized by the air permeability coefficient (mL·cm ^-2 ·min ^-1 ·bar ^-1 ), Q is characterized by the permeated gas flow rate (ml/min), and ΔP is characterized by the transmembrane pressure difference (bar), that is, the setting Test pressure; S is characterized by the effective area of the membrane (cm ² );

S8, after the pressure of the control device is released, switch to the constant pressure mode, set the test pressure, pressure increase time, and voltage stabilization test time, control the use of a nitrogen high-pressure cylinder to start the pressure increase, and conduct a membrane integrity test, wherein the test The value range of the pressure is 0.1MPa-0.3MPa, the value range of the pressure increase time is 5min-10min, and the voltage stabilization test time is not less than 30min;

S9, after the pressure of the control device is released, in the same constant pressure mode, the control uses an oxygen high-pressure cylinder to start the pressure increase. When the pressure is constant, the gas flow detection module detects the flow of oxygen gas in real time;

S10, after the pressure of the control device is released, in the same constant pressure mode, the control uses a high-pressure carbon dioxide gas cylinder to start the pressure increase. When the pressure is constant, the flow of carbon dioxide gas is detected in real time through the gas flow detection module;

S11, calculate the ratio between any two of the transmitted nitrogen gas flow, the transmitted oxygen gas flow, and the transmitted carbon dioxide gas flow. The ratio is determined by the larger value compared to the smaller value;

S12. If any ratio is much greater than 1, it is determined that the integrity of the membrane module is good. If there is a ratio that is close to 1, it is determined that there is a problem with the integrity of the membrane module;

Specifically, for example, if the ratio is greater than 10, it is determined to be much greater than 1, and the integrity of the membrane module is good. If the ratio is 0.9-1.1, it is determined that the ratio is close to 1, and there is a problem with the integrity of the membrane module.

S13, after the control device releases pressure, switch to the pressure boost mode, set the maximum test pressure, pressure boost time, control the start of pressure boost, and conduct an internal explosion pressure test;

S14, during the pressure boosting process, the gas flow detection module detects the permeated gas flow in real time, and the inlet side pressure sensor detects the test pressure in real time, and generates a test pressure-permeated gas flow relationship curve;

S15, if the increase value of the permeated gas flow rate per unit time is greater than the preset value, it is determined that the membrane is ruptured, the pressure increase is stopped, and the maximum test pressure corresponding to the permeated gas flow rate per unit time is determined to be the burst pressure within the membrane;

Specifically, for example, the unit time is set to 5s and the default value is 5ml/min.

S16, when the test is completed, control to save data, reset pressure, remove components, and turn off power.

Through the operation method of the above-mentioned integrated device for testing breathable membrane performance, the detection of air permeability coefficient, membrane integrity, and burst pressure within the membrane is realized, and the air permeability coefficient, membrane integrity, and burst pressure within the membrane are quantified, which facilitates the evaluation of product performance. Comparison, and the detection method is simple, the test data is reliable, and the accuracy is high. After the membrane module is installed once, the three performance parameters of air permeability, membrane integrity, and intra-membrane burst pressure can be tested in sequence, which greatly improves the testing efficiency. At that time, in actual operation, it can also be completed during installation and pre-inspection. Then only one or two performance parameters are tested. It should be noted that the in-membrane burst pressure test needs to be ranked last.

In addition, after the pressure of the control device is relieved, if the gas needs to be replaced, open the first solenoid valve of the upper unit of the component test module, drain the original gas through boosting the pressure, then close the first solenoid valve and start the next program. The detection accuracy will be further improved.

The integrated device for testing the breathable membrane performance and its operation method proposed by the present invention can not only quickly and accurately test the burst pressure in the separation membrane, but also comprehensively evaluate the breathable performance and integrity of the separation membrane, realizing a true multi-purpose machine; The device also has a real-time online monitoring function of numerical values, timely data feedback, and high measurement accuracy; this test operation method is of great significance to the improvement of the current domestic breathable membrane performance evaluation methods. The device has a beautiful appearance, is easy to disassemble, and has a simple and practical operation method. Suitable for the research and application of hollow fiber breathable membrane technology.

The above-mentioned embodiments only express several implementation modes of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the patent scope of the present invention. It should be noted that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the scope of protection of the patent of the present invention should be determined by the appended claims.

Claims (6)

1. An air permeable membrane performance test integrated device, comprising:

the device comprises a component test module, a pressure driving control module connected with a top pipeline of the component test module, a gas flow detection module connected with the bottom of the component test module, and a control system respectively connected with the component test module, the pressure driving control module and the gas flow detection module in a communication way, wherein the component test module comprises:

the upper unit, middle part unit and lower part unit of sealing connection from top to bottom in proper order, the upper unit with pressure drive module passes through the pipe connection, the upper unit includes: an upper cylinder; the air inlet is arranged on the top surface of the upper cylinder body and is connected with the pressure driving module through a pipeline; the first exhaust port is arranged on the side surface of the upper cylinder body, and a first electromagnetic valve is arranged on an exhaust pipeline connected with the first exhaust port; the air inlet side pressure sensor is connected to the side surface of the upper cylinder body, the height of the connecting position of the air inlet side pressure sensor on the upper cylinder body is higher than the height of the first exhaust port, and the air inlet side pressure sensor is in communication connection with the control system;

the middle unit is provided with a through hole and a non-through hole from bottom to top, the bottom end of the through hole is detachably connected with a quick-twist joint, the bottom end of the quick-twist joint is detachably connected with a membrane assembly, and the bottom end of the non-through hole is detachably connected with a supporting rod;

the lower unit includes: a lower cylinder; the second exhaust port is arranged on the side surface of the lower cylinder body, is connected with the gas flow detection module through a pipeline, and is provided with a second electromagnetic valve on an exhaust pipeline connected with the second exhaust port; a gas permeation side pressure sensor connected to the side surface of the lower cylinder, wherein the height of the connection position of the gas permeation side pressure sensor on the lower cylinder is higher than the height of the second exhaust port, and the gas permeation side pressure sensor is in communication connection with the control system;

the upper unit, the middle unit and the lower unit are connected in a sealing way through threads and sealing rings, and the upper end and the lower end of the middle unit are sleeved in the upper unit and the lower unit respectively;

the pressure driving control module includes: the high-pressure gas cylinders are connected in parallel and are respectively connected with the component test module through pipelines, a pressure reducing valve is arranged on a gas outlet connecting pipeline of each high-pressure gas cylinder, and an electric proportional regulating valve is arranged on a connecting pipeline close to the component test module;

the plurality of high-pressure gas cylinders arranged in parallel are respectively filled with different gases, including but not limited to nitrogen, oxygen and carbon dioxide;

the operation method of the ventilation film performance test integrated device comprises the following steps:

installing two ends of a membrane assembly on quick-screwing joints of a middle unit of an assembly test module, adjusting the height of a supporting rod, and straightening down a separation membrane to be uniformly distributed;

the middle unit is tightly screwed and hermetically connected with the upper unit and the lower unit, and the assembly testing module is sequentially connected with the pressure driving and controlling module, the air inlet side pressure sensor, the air outlet side pressure sensor and the air outlet pipeline;

starting a control system, opening a specified high-pressure gas cylinder and a pressure reducing valve thereof after the control system normally operates, and adjusting the test pressure;

setting pre-detection pressure, boosting time and stabilizing time in a constant pressure mode, opening a first electromagnetic valve connected with an upper unit of the component testing module and a second electromagnetic valve connected with a lower unit of the component testing module, controlling boosting, fully discharging air in the device, and then closing the first electromagnetic valve;

after pressure stabilization, monitoring a permeation side pressure through a gas permeation side pressure sensor, and if the monitored permeation side pressure is maintained within a specified pressure range for a specified duration, determining that the membrane assembly is intact and the air tightness of the device is not problematic;

after the control device is depressurized, performing an air permeability coefficient test or a membrane module integrity test or an internal bursting pressure test or sequentially performing an air permeability coefficient test and a membrane module integrity test or sequentially performing an air permeability coefficient test and an internal bursting pressure test or sequentially performing a membrane module integrity test and an internal bursting pressure test or sequentially performing an air permeability coefficient test, a membrane module integrity test and an internal bursting pressure test;

after the test is completed, the data is saved, the pressure is reset, the assembly is removed, and the power supply is turned off.

2. The integrated device for testing the performance of the breathable film according to claim 1, wherein,

the through holes and the non-through holes formed in the middle unit are distributed in a cross manner, two through holes are formed in the through holes, two non-through holes are formed in the through holes, the through holes and the quick screwing connectors are arranged one by one, and the non-through holes and the connecting rods are arranged one by one.

3. The integrated device for testing the performance of the breathable film according to claim 2, wherein,

the support rod is a telescopic adjusting support rod, and the length adjusting range of the telescopic adjusting support rod is 5cm-15cm; the gas flow detection module is a high-precision gas flowmeter, and the measuring range of the high-precision gas flowmeter is 0-100ml/min.

4. The breathable film performance test integration device of claim 1, wherein the breathable coefficient test comprises the steps of:

under a constant pressure mode, setting test pressure, boosting time and stabilizing test time, and controlling to start boosting, wherein the value range of the test pressure is 0.1-0.3 MPa, the value range of the boosting time is 5-10 min, and the stabilizing test time is not less than 30min;

when the pressure is constant, detecting the flow of the permeated gas in real time through a gas flow detection module;

according to the permeate gas flow, calculating the air permeability coefficient according to a preset formula, wherein the preset formula is as follows:

，

wherein F is characterized by the permeability coefficient (mL.cm ^-2 •min ^-1 •bar ^-1 ) Q is characterized by permeate gas flow (ml/min), ΔP is characterized by transmembrane pressure difference (bar), i.e., set test pressure; s is characterized by the effective area (cm) of the membrane ² ）。

5. The air permeable membrane performance test integration device of claim 1, wherein the membrane assembly integrity test comprises the steps of:

setting test pressure, boosting time and stabilizing test time under a constant pressure mode, and controlling to start boosting by using a nitrogen high-pressure gas cylinder, wherein the value range of the test pressure is 0.1-0.3 MPa, the value range of the boosting time is 5-10 min, and the stabilizing test time is not less than 30min;

when the pressure is constant, detecting the flow of the permeated nitrogen gas in real time through a gas flow detection module;

after the pressure is relieved, the control device controls the oxygen high-pressure gas cylinder to start up and boost under the same constant pressure mode, and after the pressure is constant, the gas flow rate detection module detects the flow rate of the permeated oxygen gas in real time;

after the pressure is relieved, the control device controls the adoption of a carbon dioxide high-pressure gas cylinder to start up and boost under the same constant pressure mode, and after the pressure is constant, the flow of the permeated carbon dioxide gas is detected in real time through the gas flow detection module;

calculating the ratio between any two of the flow of the permeated nitrogen gas, the flow of the permeated oxygen gas and the flow of the permeated carbon dioxide gas, wherein the ratio is determined by a larger value and a smaller value;

if any ratio is far greater than 1, determining that the integrity of the membrane assembly is good;

if there is a ratio approaching 1, then there is a problem in determining the integrity of the membrane module.

6. The breathable film performance test integrated device of claim 1, wherein the implosion pressure test comprises the steps of:

setting maximum test pressure, boosting time and controlling starting boosting under the boosting mode;

in the boosting process, the flow of the permeation gas is detected in real time through a gas flow detection module, the test pressure is detected in real time through an air inlet side pressure sensor, and a relation graph of the test pressure and the permeation gas flow is generated;

if the increase value of the permeation gas flow rate in unit time is larger than a preset value, determining that the membrane is broken, stopping boosting, and determining that the maximum value of the test pressure corresponding to the permeation gas flow rate in unit time is the burst pressure in the membrane.