Non-contact hollow fiber membrane integrity detection device

Abstract

The application belongs to the technical field of visual detection, and particularly relates to a non-contact hollow fiber membrane integrity detection device, which comprises a gas conveying device, a film, an optical detection set, a detection displacement platform and an upper computer; the detection displacement platform is used for driving the hollow fiber membrane assembly to be detected to move, the gas conveying device is used for inputting gas for the hollow fiber membrane assembly to be detected, the film is firmly attached to the end face of the hollow fiber membrane assembly to be detected, the optical detection set is located directly above the detection displacement platform and is used for detecting the hollow fiber membrane assembly to be detected, and the optical detection set transmits the detected information to the upper computer. The device adopts optical non-contact measurement, is faster, has higher precision, better saves detection cost and later maintenance cost, has a large measurement range, is suitable for various hollow fiber membrane assemblies, has no damage to the membrane filaments, has high universality and strong applicability.

Description

Technical Field

[0001] This invention belongs to the field of visual inspection technology, specifically relating to a non-contact hollow fiber membrane integrity detection device. Background Technology

[0002] Hollow fiber membranes are a type of ultrafiltration membrane, representing the most mature and advanced form of ultrafiltration technology. With a filtration precision ranging from 0.005 to 0.01 μm, they effectively remove various impurities, bacteria, and other organic matter from water, playing a significant role in the separation, concentration, and purification of substances. Initially used in pharmaceuticals, brewing, catering, chemicals, municipal wastewater reuse, hospital and residential wastewater reuse, and papermaking for wastewater treatment, hollow fiber membranes have expanded to include food processing, beverage processing, dairy processing, bio-fermentation, biopharmaceuticals, pharmaceutical chemicals, biological agents, traditional Chinese medicine preparations, clinical medicine, dyeing and printing wastewater treatment, food industry wastewater treatment, resource recycling, and environmental engineering.

[0003] Chinese patent discloses a hollow fiber membrane module integrity testing device (application number: 201510264009.8). This device includes a reactor, an aeration device, and a water pump. Two pairs of platinum wire probes are installed on the inlet pipe connected to the water pump. Two circuits are connected in parallel to a 5V power supply. Each pair of platinum wire probes is connected in series with a fixed resistor in the circuit. Each resistor is also connected in parallel with a fixed capacitor. The two ends of each fixed resistor are connected to a data acquisition card via wires. The data acquisition card collects the voltage across the fixed resistors and connects to a computer via a data cable. The integrity of the hollow fiber membrane module is determined based on the online voltage change display. This device uses electrical principles to collect voltage changes across fixed resistors and judges the membrane module integrity based on the voltage signal change pattern. However, such methods for detecting the integrity of hollow fiber membrane modules are all contact-based measurements, or can only detect the integrity of single filaments and not the integrity of complete hollow fiber membrane modules. The detection cost and subsequent maintenance cost are high, and it cannot locate the location of defective filaments in the module. Summary of the Invention

[0004] The purpose of this invention is to provide a non-contact hollow fiber membrane integrity testing device to solve the problems existing in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a non-contact hollow fiber membrane integrity detection device, comprising a gas supply device, a thin film, an optical detection sleeve, a detection displacement platform, and a host computer; the detection displacement platform is used to move the hollow fiber membrane assembly to be tested located thereon; the gas supply device is used to input gas into the hollow fiber membrane assembly to be tested; the thin film is firmly attached to the end face of the hollow fiber membrane assembly to be tested; the optical detection sleeve is located directly above the detection displacement platform and is used to detect the hollow fiber membrane assembly to be tested; the optical detection sleeve transmits the detected information to the host computer.

[0006] Preferably, the optical inspection kit includes a line laser and an industrial camera with a lens. The line laser faces directly downwards towards the inspection displacement platform, and the industrial camera with a lens is on the same horizontal plane as the line laser and is aimed at the location of the laser line to take pictures.

[0007] Preferably, the gas delivery device includes a gas source and a pressure reducing valve, wherein the gas source is connected to the air inlet of the hollow fiber membrane module through the pressure reducing valve.

[0008] Preferably, a cavity pressure monitoring gauge is installed on the hollow fiber membrane assembly.

[0009] Preferably, the distance between the linear laser and the detection end face of the hollow fiber membrane module is between 150mm and 300mm, and the line width is no more than 0.4mm.

[0010] Preferably, the line laser is mounted on an adjustable bracket.

[0011] A non-contact hollow fiber membrane integrity testing method, using the aforementioned testing device, includes the following steps: Step S1, covering the testing end of the hollow fiber membrane module with a thin film; Step S2: With the detection end facing upward, vertically fix the hollow fiber membrane assembly covered with the film onto the horizontal displacement stage; Step S3: Connect the hollow fiber membrane module to the air inlet, pressure reducing valve, air source, and chamber pressure monitoring gauge; Step S4: Turn on the linear laser and industrial camera, start the horizontal displacement stage to begin detection, and transmit the received image to the computer for processing to obtain the location of the defect wire. Step S5: Once the horizontal displacement stage has completed its stroke, the test is finished.

[0012] The beneficial effects of this invention are: This invention adopts optical non-contact measurement, which is faster, more accurate, and saves more on testing and maintenance costs. It has a large measurement range, is applicable to various hollow fiber membrane modules, does not damage the membrane fibers, and has high versatility and strong applicability. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the present invention. Detailed Implementation

[0014] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings and preferred embodiments.

[0015] like Figure 1 As shown, a non-contact hollow fiber membrane integrity testing device includes a gas supply device, a thin film, an optical detection kit, a detection displacement platform, and a host computer. The gas supply device consists of a gas source 6 that continuously outputs a quantitative amount of gas and a pressure reducing valve 5. The thin film 2 is a thin film 2 that can be firmly attached to the end face of the hollow fiber membrane assembly 3 to be tested. The optical detection kit includes a line laser 1, an industrial camera, and a lens 10. The line laser 1 is equipped with a fixed and adjustable bracket. The industrial camera and lens 10 are connected. The detection displacement platform is a horizontal displacement platform 7 that fixes the hollow fiber membrane assembly 3. The host computer is a computer 9 that processes data and is connected to the industrial camera, lens, and horizontal displacement platform 7 via a data interface. After connection, the industrial camera and lens are positioned in a V-shape above the detection displacement platform on the same horizontal plane as the line laser 1, with the line laser 1 facing directly downwards towards the detection displacement platform, and the industrial camera and lens 10 facing the location of the laser line to capture images. Furthermore, the membrane must be tightly adhered to the end face of the hollow fiber membrane module's detection end before gas is introduced. The hollow fiber membrane module must be vertically and firmly mounted on the horizontal displacement stage. The distance between the line laser and the end face of the hollow fiber membrane module's detection end should be between 150mm and 300mm. During the detection process, the gas source should continuously and stably input gas. The line width of the line laser should not exceed 0.4mm, and the working distance should be between 150mm and 300mm. The hollow fiber membrane module needs to be connected to a cavity pressure monitoring gauge, and a pressure reducing valve needs to be connected between the air inlet and the gas source to control the input gas flow rate.

[0016] This invention is based on the following principle: After gas is introduced, the thin film attached to the end face of the hollow fiber membrane module will undulate to varying degrees due to the increased gas pressure inside the cavity. The film at the location of the defect wire will have a relatively larger bulge. A line laser emits a laser beam that illuminates the film, causing diffuse reflection. The imaging system focuses part of the reflected light at another angle, and the light spot will be imaged in the camera. When the surface of the thin film undulates, the angle of the reflected light will also change, and the image formed by the light spot will move accordingly. The imaging position and the position of the laser axis have a unique correspondence. After measuring the center position of the light spot, the depth coordinates of the light spot can be calculated through the optical geometric relationship between the light spot and its image point position, that is, the depth information of the thin film surface can be obtained. After processing by the host computer, the coordinates of the defect position can be obtained.

[0017] The operating steps of the optical non-contact hollow fiber membrane module integrity testing device include: Step S11: Cover the detection end of the hollow fiber membrane module with a thin film; Step S12: With the detection end facing upward, vertically fix the hollow fiber membrane assembly covered with the film onto the horizontal displacement stage; Step S13: Connect the air inlet, pressure reducing valve, and air source; connect the pressure measuring port and pressure monitoring gauge. Step S14: Turn on the linear laser and industrial camera, start the horizontal displacement stage to begin detection, and transmit the received image to the computer for processing to obtain the location of the defect wire.

[0018] Step S15: Once the horizontal displacement stage has completed its stroke, the test is finished.

[0019] It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention.

Claims

1. A non-contact hollow fiber membrane integrity testing device, characterized in that: The system includes a gas delivery device, a membrane, an optical inspection kit, a detection displacement platform, and a host computer. The detection displacement platform is used to move the hollow fiber membrane module to be inspected located on it. The gas delivery device is used to input gas into the hollow fiber membrane module to be inspected. The membrane is firmly attached to the end face of the hollow fiber membrane module to be inspected. The optical inspection kit is located directly above the detection displacement platform and is used to inspect the hollow fiber membrane module to be inspected. The optical inspection kit transmits the inspection information to the host computer. The optical inspection kit includes a line laser and an industrial camera with a lens. The line laser faces directly downwards towards the inspection displacement platform, and the industrial camera with a lens is on the same horizontal plane as the line laser and is aimed at the location of the laser line to take pictures. After gas is introduced, the membrane attached to the end face of the hollow fiber membrane module will fluctuate to varying degrees due to the increase in gas pressure inside the cavity.

2. The non-contact hollow fiber membrane integrity detection device according to claim 1, characterized in that: The gas delivery device includes a gas source and a pressure reducing valve, and the gas source is connected to the air inlet of the hollow fiber membrane module through the pressure reducing valve.

3. The non-contact hollow fiber membrane integrity detection device according to claim 1, characterized in that: The hollow fiber membrane module is equipped with a cavity pressure monitoring gauge.

4. The non-contact hollow fiber membrane integrity testing device according to claim 1, characterized in that: The distance between the linear laser and the detection end face of the hollow fiber membrane module is between 150mm and 300mm, and the line width is no greater than 0.4mm.

5. The non-contact hollow fiber membrane integrity testing device according to claim 1, characterized in that: The line laser is mounted on an adjustable bracket.

6. A non-contact method for detecting the integrity of hollow fiber membranes, characterized in that: Using the detection device according to any one of claims 1-5, the method includes the following steps: Step S1, covering the detection end of the hollow fiber membrane module with a thin film; Step S2: With the detection end facing upward, vertically fix the hollow fiber membrane assembly covered with the film onto the horizontal displacement stage; Step S3: Connect the hollow fiber membrane module to the air inlet, pressure reducing valve, air source, and chamber pressure monitoring gauge; Step S4: Turn on the linear laser and industrial camera, start the horizontal displacement stage to begin detection, and transmit the received image to the computer for processing to obtain the location of the defect wire. Step S5: Once the horizontal displacement stage has completed its stroke, the test is finished.

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