Reverse osmosis membrane microbubble off-line cleaning and testing device

Abstract

The utility model discloses a reverse osmosis membrane microbubble off-line cleaning and testing device which comprises a cleaning system and a testing system connected with the cleaning system, and further comprises an instrument, necessary pipelines and valves, the cleaning system comprises a micro-nano bubble generating device and an acid-base cleaning water tank connected with the micro-nano bubble generating device, and an acid-base cleaning water pump and a cleaning security filter are arranged between the micro-nano bubble generating device and the acid-base cleaning water tank; the off-line cleaning membrane shell is connected with the acid-base cleaning water tank to form a closed loop; the off-line cleaning membrane shell is connected with the acid-base cleaning water tank to form a closed loop; the test system comprises an RO raw water tank, an RO water supply pump, an RO cartridge filter, an RO high-pressure pump and the like. The micro-nano bubble technology is applied to reverse osmosis membrane cleaning, the cleaning effect is improved, and the service life of the membrane is prolonged.

Description

Technical Field

[0001] The utility model relates to the field of reverse osmosis cleaning, in particular to a reverse osmosis membrane micro-bubble offline cleaning and testing device. Background Art

[0002] Currently, reverse osmosis membranes are widely used in numerous fields, including petrochemicals, steel, pharmaceuticals, food and beverages, municipal administration, and environmental protection. They play an indispensable role in seawater desalination, boiler feed water, pure drinking water production, and wastewater treatment. During the reverse osmosis membrane separation process, tiny particles, colloids, or macromolecules in the material interact physically, chemically, or mechanically with the membrane pores. This causes various solid substances or solute components to adsorb and deposit within the membrane pores, reducing or clogging the pore size. Membrane fouling increases separation resistance, reduces water production and salt rejection, increases differential pressure, and shortens the membrane's service life. Therefore, timely cleaning of contaminated membranes is essential to ensure the safe and stable operation of the reverse osmosis system and extend the life of the reverse osmosis membrane.

[0003] At the same time, since the cleaning results cannot be verified in time, it brings inconvenience to the reuse of the membrane elements after cleaning. Utility Model Content

[0004] Therefore, the technical problem to be solved by the present invention is to apply micro-nano bubble technology to reverse osmosis membrane cleaning, and to provide a device that can improve the cleaning effect, extend the service life of the membrane, and simultaneously test the cleaning effect and membrane performance recovery.

[0005] The technical solution is a reverse osmosis membrane microbubble offline cleaning and testing device, the device comprising a cleaning system connected to a testing system, instruments, and necessary pipes and valves; the cleaning system comprising a micro-nano bubble generator 10, an acid-base cleaning water tank 11 connected to the micro-nano bubble generator 10, an acid-base cleaning water pump 12 and a cleaning safety filter 13 disposed between the micro-nano bubble generator 10 and the acid-base cleaning water tank 11; an offline cleaning membrane housing 19 connected to the acid-base cleaning water tank 11 to form a closed loop;

[0006] The test system includes an RO raw water tank 1, a RO water supply pump 3, and a RO safety filter 5. An RO raw water tank outlet valve 2 is connected between the RO raw water tank 1 and the RO water supply pump 3, and an RO water inlet pump outlet valve 4 is connected between the RO water supply pump 3 and the RO safety filter 5; the outlet of the RO safety filter 5 is connected to a RO high-pressure pump 6, and the RO high-pressure pump 6 is connected to the test system membrane shell 20; the RO device includes an offline cleaning membrane shell 19 and a test system membrane shell 20, and the number of the offline cleaning membrane shells is greater than that of the test system membrane shells.

[0007] In the present reverse osmosis membrane microbubble offline cleaning and testing device, the offline cleaning membrane housing 19 and the testing system membrane housing 20 are arranged on a set of membrane group devices.

[0008] The RO system refers to the entire membrane element and membrane housing. The cleaning system connects to the offline cleaning membrane housing of the RO system, while the test system connects to the test system membrane housing of the RO system. The test system portion of the RO system operates at higher pressures due to the pump and membrane filtration, while the cleaning portion operates at lower pressures. Therefore, the connection materials and membrane housing requirements differ.

[0009] Furthermore, the ratio of the number of membrane tubes in the offline cleaning membrane shell to that in the test system membrane shell is 4-6:1.

[0010] In this reverse osmosis membrane microbubble offline cleaning and testing device, the interface of the micro-nano bubble generating device is a flange or a quick-install interface. The interface is directly embedded and installed in the original water pipeline. The micro-nano bubble generating device must be turned on during the flushing and circulation processes. The micro-nano bubble generating device can be selected from flanges or quick-install interfaces according to needs and directly embedded and installed in the original water pipeline. The hydraulic shear cavitation micro-nano bubble generating device is driven by the original water pressure of the original water pipeline. The formed micro-nano bubble gas-liquid system can enhance the mass transfer process, increase the shear force on the membrane surface, affect the formation of the membrane surface fouling layer, and increase the membrane flux.

[0011] In the present reverse osmosis membrane microbubble offline cleaning and testing device, a produced water cleaning reflux valve 17 and a concentrated water cleaning reflux valve 18 are provided on the connection passage between the offline cleaning membrane housing 19 and the acid-base cleaning water tank 11 .

[0012] In this reverse osmosis membrane microbubble offline cleaning and testing device, the acid and alkali cleaning water tank is provided with a cleaning water tank outlet valve; the acid and alkali cleaning water pump is provided with a cleaning water pump outlet valve; and the RO device is provided with an RO device cleaning water inlet valve.

[0013] The cleaning system valves include a cleaning water tank outlet valve, a cleaning water pump outlet valve, an RO device cleaning water inlet valve, a produced water cleaning return valve, and a concentrated water cleaning return valve.

[0014] In the reverse osmosis membrane microbubble offline cleaning and testing device, the cleaning system instruments include a magnetic flap level meter, an electromagnetic flow meter, an online pH meter, and a pressure sensor.

[0015] In this reverse osmosis membrane microbubble offline cleaning and testing device, the cleaning and testing systems are connected to an electronic control system. The testing and cleaning systems are centrally controlled within a single control module. The pumps and valves are individually controlled with start and stop buttons.

[0016] In the reverse osmosis membrane microbubble offline cleaning and testing device, the test system instruments include a magnetic flap level meter, an electromagnetic flow meter, an inlet water conductivity meter, a product water conductivity meter, and a pressure sensor.

[0017] The utility model provides a reverse osmosis membrane microbubble offline cleaning and testing device. The device is used for offline cleaning and performance testing of reverse osmosis membranes. The device introduces micro- and nano-bubbles into contaminated membrane element cleaning applications, utilizing the high-pressure explosion within the micro- and nano-bubbles and the friction and shearing effects of the gas-liquid system to enhance the cleaning effect. It can also test the cleaning effect and assess the membrane's post-cleaning performance recovery. This device improves cleaning effectiveness, extends membrane service life, and reduces maintenance costs.

[0018] This device is designed to achieve offline microbubble cleaning and testing of reverse osmosis membranes in industrial wastewater zero-discharge process membrane systems. It features excellent cleaning results, simple equipment, and the ability to perform both offline cleaning and testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Flow chart of the reverse osmosis membrane microbubble offline cleaning and testing device.

[0020] Among them, 1-RO raw water tank; 2-RO raw water tank outlet valve; 3-RO water inlet pump; 4-RO water inlet pump outlet valve; 5-RO safety filter; 6-RO high-pressure pump; 7-RO device inlet valve; 8-RO device production water valve; 9-RO device concentrate valve; 10-micro-nano bubble generating device; 11-acid and alkali cleaning water tank; 12-acid and alkali cleaning water pump; 13-cleaning safety filter; 14-cleaning water tank outlet valve; 15-cleaning water pump outlet valve; 16-RO device cleaning water inlet valve; 17-production water cleaning return valve; 18-concentrated water cleaning return valve; 19-offline cleaning membrane shell; 20-test system membrane shell. DETAILED DESCRIPTION

[0021] The specific embodiments of the present invention are described in further detail below with reference to the accompanying drawings.

[0022] This offline reverse osmosis membrane microbubble cleaning and testing device introduces micro-nano bubbles into contaminated membrane element cleaning applications, enabling offline cleaning and performance testing of reverse osmosis membranes. The device consists of a cleaning system and a testing system. The cleaning system includes a micro-nano bubble generator 10, an acid-base cleaning water tank 11, an acid-base cleaning water pump 12, a cleaning safety filter 13, an RO unit, piping, instruments, valves, and an electronic control system. The testing system includes an RO raw water tank 1, an RO water supply pump 3, an RO safety filter 5, an RO high-pressure pump 6, piping, instruments, valves, and an electronic control system.

[0023] The membrane chemical offline cleaning process includes three processes: flushing, soaking and circulation: reverse osmosis produced water is added to the cleaning water tank, and the cleaning agent is prepared according to the required concentration. The cleaning agent is pressurized by the cleaning water pump, and the safety filter filters out particles larger than 10um. The particles enter the individual membrane shells respectively. In the membrane shells, the cleaning agent flows through the reverse osmosis membrane elements to form two water flows, namely, concentrated water and produced water. The water flows pass through the concentrated water side cleaning return valve and the produced water side cleaning return valve respectively and then return to the cleaning water tank for the flushing, soaking and circulation process.

[0024] The chemical cleaning process of the RO system includes two flushing processes: the flushing at the beginning of the chemical cleaning can effectively scrub the dirt on the membrane surface; the flushing after the chemical cleaning is completed can effectively remove the chemical cleaning solution, providing a necessary guarantee for the quality of the product water.

[0025] Soaking is the key to RO system cleaning. It not only allows the chemical liquid to react with the pollutants, but also allows the pollutants to fall off the surface of the membrane and dissolve in the chemical liquid to achieve the purpose of chemical cleaning.

[0026] The circulation process is the main cleaning process of the RO system. During this process, the chemical liquid comes into physical contact with the molecules inside the membrane, and further reactions such as penetration, friction, and shearing occur, thereby achieving the purpose of chemical cleaning.

[0027] The micro-nano bubble generator must be activated during both the flushing and circulation processes. It can be installed directly into the raw water pipeline using a flange or quick-release connector, utilizing the existing water pressure in the raw water pipeline to drive the hydraulic shear cavitation micro-nano bubble generator. The resulting micro-nano bubble gas-liquid system enhances mass transfer, increases shear force on the membrane surface, mitigates the formation of a fouling layer on the membrane surface, and improves membrane flux.

[0028] The cleaning system valves include the cleaning water tank outlet valve 14, the cleaning water pump outlet valve 15, the RO device cleaning water inlet valve 16, the produced water cleaning return valve 17, the concentrated water cleaning return valve 18, etc.

[0029] The cleaning system instruments include a magnetic flap level gauge, an electromagnetic flow meter, an online pH meter, a pressure sensor, etc.; the magnetic flap level gauge and the online pH meter are located in the acid and alkali cleaning water tank, and the pressure sensor is connected to the water inlet and outlet positions of the safety filter and the membrane shell respectively.

[0030] The membrane system test process is as follows: after cleaning, reverse osmosis water is injected into the cleaning water tank, and a cleaning water pump is used to displace the wastewater after membrane washing out of the system through produced water and concentrated water. A sampling valve is provided at the outlet of each membrane. The test is completed with neutral flushing, and then a recovery performance test is carried out.

[0031] Add reverse osmosis water into the RO raw water tank, pressurize it with the RO water supply pump, and filter out particles larger than 5um with the RO safety filter. Turn on the RO high-pressure pump to increase the water inlet pressure, and let it enter the membrane shell respectively. The water flux of the membrane can be tested by the water flow rate, and the desalination rate can be calculated by the water conductivity to evaluate the cleaning plan and the recovery of the desalination performance.

[0032] The test system valves include RO raw water tank outlet valve 2, RO water pump outlet valve 4, RO device inlet valve 7, RO device water production valve 8, RO device concentrated water valve 9, etc.

[0033] The test system instruments include a magnetic level gauge, an electromagnetic flowmeter, an inlet water conductivity meter, a product water conductivity meter, and a pressure sensor. The magnetic level gauge is located in the RO inlet tank, the electromagnetic flowmeter is located after the inlet pump, the inlet water conductivity meter is located in the pipe after the RO inlet tank, and the product water conductivity meter is located in the membrane housing and product water pipeline. The pressure sensor is connected to the safety filter and the membrane housing water inlet and outlet.

[0034] The electronic control system of the microbubble offline cleaning and testing device consists of a PLC module, electrical components, and a control cabinet. The control cabinet is equipped with a start button, a stop button, a power indicator, an operating indicator, an audible and visual alarm, and an emergency stop button for the entire system. Its primary function is to control the device's start and stop.

[0035] like Figure 1 After the device arrives at the site, install the reverse osmosis offline cleaning device site, prepare the water supply and drainage facilities, make electrical connections, and carry out equipment installation and commissioning. Test the membrane components, water tanks, pumps, micro-nano bubble generators, dosing systems, valves, instruments, and electronic control systems to ensure that the equipment is in normal use;

[0036] When the device's cleaning system is operating: open the cleaning water tank outlet valve 14, the cleaning water pump outlet valve 15, the reverse osmosis cleaning inlet valve 16, the produced water cleaning return valve 17, and the concentrated water cleaning return valve 18. Close all other valves. After priming the cleaning water pump 12, turn the cleaning pump start knob on the electrical control box to start the acid-base cleaning water pump 12 and the micro-nano bubble generator 10. After completing the three cleaning processes of rinsing, soaking, and circulating according to the cleaning plan, stop the cleaning water pump 12, open the cleaning water tank drain valve, and drain all the water from the cleaning system.

[0037] When the device test system is in operation: reverse osmosis water is injected into the acid and alkali cleaning water tank 11, and the acid and alkali cleaning water pump 12 is used to replace the wastewater after membrane washing out of the system through produced water and concentrated water. A sampling valve is provided at the outlet of each membrane. The detection is completed with neutral flushing, and then the recovery performance test is carried out.

[0038] Place the cleaned membrane element in the membrane housing 20 of the test device, add reverse osmosis water into the RO raw water tank 1, open the RO raw water tank outlet valve 2, the RO water inlet pump outlet valve 4, the RO device inlet valve 7, the RO device water valve 8, and the RO device concentrated water valve 9.

[0039] After pressurization by the RO water inlet pump 3, the RO safety filter 5 filters out particles larger than 5 μm. When the pressure of the low-pressure protection switch in front of the high-pressure pump 6 is ≥0.1 MPa, the RO high-pressure pump 6 is turned on to increase the inlet pressure of water, and the water enters the test membrane shell 20 respectively. The water flux of the membrane can be tested by the water flow rate, and the desalination rate can be calculated by the water conductivity to evaluate the cleaning plan and the recovery of the desalination performance.

[0040] The reverse osmosis membrane microbubble offline cleaning and testing device incorporates a micro-nano bubble air-water cleaning system, integrating cleaning and testing. This device enhances membrane fouling cleaning while also verifying and evaluating cleaning results. It provides basic data and effective evaluation for membrane element reuse.

[0041] This utility model proposes a reverse osmosis membrane microbubble offline cleaning and testing device, applying micro-nano bubble technology to reverse osmosis membrane cleaning. By injecting micro-nano bubbles into the reverse osmosis cleaning solution, membrane contaminants are removed from the membrane surface, improving cleaning effectiveness, extending the membrane's service life, and reducing maintenance costs. The cleaning device is also equipped with a testing system to simultaneously verify the effectiveness of the cleaning effect.

Claims

1. A reverse osmosis membrane microbubble offline cleaning and testing device, the device comprising a cleaning system, characterized in that: The cleaning system is connected to a test system and also includes instruments, necessary pipes and valves; the cleaning system includes a micro-nano bubble generating device (10), an acid-base cleaning water tank (11) connected to the micro-nano bubble generating device (10), an acid-base cleaning water pump (12) and a cleaning safety filter (13) are provided between the micro-nano bubble generating device (10) and the acid-base cleaning water tank (11); an offline cleaning membrane shell (19) is connected to the acid-base cleaning water tank (11) to form a closed loop; The test system comprises an RO raw water tank (1), an RO water supply pump (3), and an RO safety filter (5); an RO raw water tank outlet valve (2) is connected between the RO raw water tank (1) and the RO water supply pump (3); an RO water inlet pump outlet valve (4) is connected between the RO water supply pump (3) and the RO safety filter (5); an RO high-pressure pump (6) is connected to the outlet of the RO safety filter (5); the RO high-pressure pump (6) is connected to the test system membrane shell (20); the RO device comprises an offline cleaning membrane shell (19) and a test system membrane shell (20); the number of the offline cleaning membrane shells is greater than the number of the test system membrane shells.

2. A reverse osmosis membrane microbubble offline cleaning and testing device according to claim 1, characterized in that: The offline cleaning membrane shell (19) and the test system membrane shell (20) are arranged on a set of membrane group devices.

3. A reverse osmosis membrane microbubble offline cleaning and testing device according to claim 2, characterized in that: The ratio of the number of membrane tubes in the offline cleaning membrane shell to that in the test system membrane shell is 4-6:

1.

4. The reverse osmosis membrane microbubble offline cleaning and testing device according to claim 1, characterized in that: The interface of the micro-nano bubble generating device is a flange or a quick-install interface.

5. The reverse osmosis membrane microbubble offline cleaning and testing device according to claim 1, characterized in that: A produced water cleaning reflux valve (17) and a concentrated water cleaning reflux valve (18) are provided on the connection passage between the offline cleaning membrane shell (19) and the acid-base cleaning water tank (11).

6. The reverse osmosis membrane microbubble offline cleaning and testing device according to claim 1, characterized in that: The acid and alkali cleaning water tank is provided with a cleaning water tank outlet valve; the acid and alkali cleaning water pump is provided with a cleaning water pump outlet valve; the RO device is provided with an RO device cleaning water inlet valve.

7. The reverse osmosis membrane microbubble offline cleaning and testing device according to claim 1, characterized in that: The cleaning system instruments include a magnetic flap level meter, an electromagnetic flow meter, an online pH meter, and a pressure sensor.

8. The reverse osmosis membrane microbubble offline cleaning and testing device according to claim 1, characterized in that: The cleaning system and the testing system are connected with an electric control system.

9. The reverse osmosis membrane microbubble offline cleaning and testing device according to claim 1, characterized in that: The test system instruments include a magnetic flap level meter, an electromagnetic flow meter, an inlet water conductivity meter, a product water conductivity meter, and a pressure sensor.

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