A tubular ultrafiltration membrane device for an integrated cleaning system

Abstract

This utility model relates to the field of wastewater treatment technology, specifically to a tubular ultrafiltration membrane device with an integrated cleaning system. The device includes a skid-mounted structure, a cleaning water tank, a cleaning water pump, a circulating water pump, a tubular ultrafiltration membrane assembly, and a piping assembly. The cleaning water tank is located at the bottom of the skid-mounted structure and connected to the cleaning water pump. The cleaning water pump is connected to the circulating water pump, which in turn is connected to the tubular ultrafiltration membrane assembly. The piping assembly connects the cleaning water tank, the cleaning water pump, the circulating water pump, and the tubular ultrafiltration membrane assembly. This utility model integrates the tubular ultrafiltration membrane device with the cleaning system, achieving integration of the tubular ultrafiltration membrane and the cleaning unit. This enhances the modular integration design of the device, resulting in a more compact layout, significantly reduced floor space, and easier equipment maintenance.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, specifically to a tubular ultrafiltration membrane device with an integrated cleaning system. Background Technology

[0002] Ultrafiltration membranes are a physical separation technology driven by pressure difference (0.1MPa-1.0MPa). Among them, tubular ultrafiltration membranes, due to their large channel diameter, strong antifouling ability, and ease of cleaning, show significant advantages in treating water containing high suspended solids and high turbidity. During the operation of tubular ultrafiltration membrane systems, membrane fouling is the main factor affecting their long-term stable operation. To restore membrane performance, the membrane modules need to be cleaned regularly. Currently, the cleaning methods for tubular ultrafiltration membranes include physical cleaning and chemical cleaning. Physical cleaning typically employs methods such as air washing, water washing, or brush cleaning; chemical cleaning mainly involves adding chemical agents such as acids and alkalis.

[0003] However, in existing integrated cleaning systems, the tubular ultrafiltration membrane device and the cleaning system are usually designed separately. This design has the following problems: First, the system layout is not compact, the footprint is large, and the engineering investment cost is high; second, the separate design makes system maintenance inconvenient and increases the difficulty of operation and maintenance; third, the on-site construction workload is large, including equipment installation, pipeline connection, and electrical control system layout, which prolongs the project construction period; finally, the separate design requires more pipeline connections and valve control, which increases the complexity of the system and the number of failure points. These problems seriously restrict the further application and promotion of tubular ultrafiltration membrane technology in the field of water treatment. Utility Model Content

[0004] The purpose of this utility model is to address the shortcomings of the existing technology by providing a tubular ultrafiltration membrane device with an integrated cleaning system, thereby solving the problems of non-compact layout, inconvenient maintenance, large investment and land occupation, large on-site construction workload and long construction period caused by the separation of tubular ultrafiltration membrane device and cleaning system in the existing technology.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] This utility model provides a tubular ultrafiltration membrane device for an integrated cleaning system, comprising:

[0007] Skid-mounted structure, cleaning water tank, cleaning water pump, circulating water pump, tubular ultrafiltration membrane module and piping assembly;

[0008] The cleaning water tank is located at the bottom of the skid-mounted structure and is connected to the cleaning water pump. The cleaning water pump is connected to the circulating water pump and the circulating water pump is connected to the tubular ultrafiltration membrane module. The pipeline assembly is used to connect the cleaning water tank, the cleaning water pump, the circulating water pump, and the tubular ultrafiltration membrane module.

[0009] The piping assembly includes a main inlet pipe, a first common pipe, a second common pipe, a product water pipe, and multiple pipes. The main inlet pipe is connected to the inlet of the circulating water pump. The first common pipe and the main inlet pipe are provided with a raw water inlet and a cleaning concentrate return outlet. The second common pipe and the main inlet pipe are provided with a cleaning inlet and a concentrate return outlet. The inlet of the product water pipe is connected to the outlet of the ultrafiltration membrane module. The outlet of the product water pipe is provided with a product water output outlet and a cleaning product water return outlet. The cleaning product water return outlet is connected to the cleaning water tank through a pipe. The multiple pipes are used to connect the main inlet pipe, the first common pipe, the second common pipe, the product water pipe, the cleaning water tank, the cleaning water pump, the circulating water pump, and the tubular ultrafiltration membrane module.

[0010] In some embodiments, the piping assembly further includes an overflow vent pipe, one end of which is connected to the outside and the other end of which is connected to the water production pipe.

[0011] In some embodiments, a first valve group is further included, which is disposed on the first common pipeline and is used to switch the functional state of the raw water inlet and the cleaning concentrate return outlet.

[0012] In some embodiments, a second valve group is further included, which is disposed in the second common pipeline and is used to switch the functional states of the cleaning inlet and the concentrate return outlet.

[0013] In some embodiments, a third valve group is also included, which is disposed in the water production pipeline and is used to switch the functional state of the water production outlet and the cleaning water return outlet.

[0014] In some embodiments, the system further includes a solenoid valve box, which is used to control the opening and closing of the first valve group, the second valve group, and the third valve group.

[0015] In some embodiments, an electrical control cabinet is also included, which is disposed on the bottom side of the skid-mounted structure and located at the bottom of the solenoid valve box.

[0016] In some embodiments, the cleaning water tank has an inspection port on the top, an vent at the bottom, a level gauge port on the side and a level gauge installed thereon, and a pH meter installed on the top of the cleaning water tank.

[0017] In some embodiments, the cleaning water tank is further provided with a stirring system.

[0018] In some embodiments, the cleaning water pump is a corrosion-resistant centrifugal pump made of 316L stainless steel.

[0019] Furthermore, the beneficial effects of this utility model are as follows:

[0020] This utility model integrates the tubular ultrafiltration membrane device with the cleaning system, thereby achieving the integration of the tubular ultrafiltration membrane and the cleaning unit. This enhances the modular integration design of the device, resulting in a more compact layout, a significantly reduced floor space, and more convenient equipment maintenance.

[0021] In addition, tubular ultrafiltration membrane devices and cleaning systems can be prefabricated and integrated in the factory, reducing the amount of on-site construction work and shortening the construction period. Furthermore, the use of tubular ultrafiltration membranes has strong anti-fouling capabilities and is suitable for water treatment applications with high turbidity and high suspended solids content, thereby improving the reliability and stability of system operation. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the tubular ultrafiltration membrane device in the integrated cleaning system of this utility model.

[0023] In the diagram: 1-skid-mounted structure, 2-main inlet pipe, 3-first common pipe, 4-second common pipe, 5-circulating water pump, 6-tubular ultrafiltration membrane module and pipe assembly, 7-product water pipe, 8-product water outlet, 9-overflow vent pipe, 10-pipe, 11-cleaning product water return port, 12-cleaning water tank, 13-cleaning water pump, 14-electrical control cabinet, 15-solenoid valve box, 16-drain port. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model. In the description of the embodiments of the present utility model, unless otherwise stated, " / " means "or", for example, A / B can mean A or B; "and / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. In addition, in the description of the embodiments of the present utility model, "multiple" means two or more. Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of this utility model, unless otherwise stated, "multiple" means two or more.

[0025] like Figure 1 As shown, this utility model provides a tubular ultrafiltration membrane device with an integrated cleaning system, comprising:

[0026] Skid-mounted structure 1, cleaning water tank 12, cleaning water pump 13, circulating water pump 5, tubular ultrafiltration membrane module 6, and pipeline 10 assembly;

[0027] The cleaning water tank 12 is located at the bottom of the skid-mounted structure 1 and is connected to the cleaning water pump 13. The cleaning water pump 13 is connected to the circulating water pump 5. The circulating water pump 5 is connected to the tubular ultrafiltration membrane module 6. The pipeline 10 assembly is used to connect the cleaning water tank 12, the cleaning water pump 13, the circulating water pump 5, and the tubular ultrafiltration membrane module 6.

[0028] The pipeline assembly 10 includes a main inlet pipeline 2, a first common pipeline 3, a second common pipeline 4, a product water pipeline 7, and multiple pipelines 10. The main inlet pipeline 2 is connected to the inlet of the circulating water pump 5. The first common pipeline 3 is connected to the main inlet pipeline 2 and has a raw water inlet and a cleaning concentrate return outlet. The second common pipeline 4 is connected to the main inlet pipeline 2 and has a cleaning inlet and a concentrate return outlet. The inlet of the product water pipeline 7 is connected to the outlet of the ultrafiltration membrane module. The outlet of the product water pipeline 7 is provided with a product water outlet 8 and a cleaning product water return outlet 11. The cleaning product water return outlet is connected to the cleaning water tank 12 through the pipeline 10. The multiple pipelines 10 are used to connect the main inlet pipeline 2, the first common pipeline 3, the second common pipeline 4, the product water pipeline 7, the cleaning water tank 12, the cleaning water pump 13, the circulating water pump 5, and the tubular ultrafiltration membrane module 6.

[0029] In the above embodiments, the cleaning water pump 13 is a corrosion-resistant centrifugal pump, and its material meets at least the 316L stainless steel standard. It has excellent corrosion resistance and can adapt to the working environment of chemical cleaning agents such as acids, alkalis, and sodium hypochlorite. This application does not make specific limitations in this regard. The pump inlet is connected to the outlet of the cleaning water tank 12 to provide the required flow rate and pressure for cleaning the tubular ultrafiltration membrane module 6.

[0030] The circulating water pump 5 is a corrosion-resistant horizontal centrifugal pump, made of material that meets at least the 316L stainless steel standard. It possesses excellent corrosion resistance and can withstand working environments with chemical cleaning agents such as acids, alkalis, and sodium hypochlorite. This application does not impose specific limitations on this aspect. The pump body is installed horizontally. The inlet of the circulating water pump 5 is connected to the raw water inlet or the cleaning water pipe, and the outlet is connected to the inlet of the ultrafiltration membrane element, forming the main circulation of the membrane filtration system. This provides sufficient cross-flow velocity and pressure for the operation and cleaning of the tubular ultrafiltration membrane module 6. The circulating water pump 5 is designed with a variable frequency control system, which can adjust the flow rate and pressure according to different operating conditions to optimize system operation.

[0031] Furthermore, the tubular ultrafiltration membrane module 6 is used for solid-liquid separation filtration. It adopts a tubular structure design, featuring strong anti-fouling ability, good cleaning effect, and long service life. It is worth noting that the tubular ultrafiltration membrane module 6 can be any commonly used tubular ultrafiltration membrane. Those skilled in the art are capable of selecting a suitable tubular ultrafiltration membrane for separation filtration; this application does not impose specific limitations in this regard. The inlet of the tubular ultrafiltration membrane module 6 is connected to the outlet of the circulating water pump 5, the product water outlet is connected to the product water pipeline, and the concentrate outlet is connected to the concentrate return port or the cleaning concentrate return port. The ultrafiltration membrane element consists of multiple tubular membranes, each with an inner diameter of 5 mm and a length of 3 meters. The membrane material is PADF, and the total filtration area is 4.8 square meters. In addition, the tubular ultrafiltration membrane element has a maximum operating pressure of 1 MPa, a maximum operating temperature of 60 degrees Celsius, and a pH range of 2-12. It adopts a modular design, with each module containing several tubular membranes. The entire system is divided into several modules, facilitating installation and maintenance.

[0032] In one possible implementation, the pipe 10 assembly also includes an overflow vent pipe 910, one end of which is connected to the outside and the other end is connected to the water production pipe 7. The overflow vent pipe 910 is used to prevent overflow caused by excessive water flow or excessive water volume during the use of the entire device of this utility model.

[0033] One possible implementation also includes a first valve group, which is installed in the first common pipeline 3 and is used to switch the functional state of the raw water inlet and the cleaning concentrate return port; a second valve group, which is installed in the second common pipeline 4 and is used to switch the functional state of the cleaning inlet and the concentrate return port; and a third valve group, which is installed in the product water pipeline 7 and is used to switch the functional state of the product water outlet 8 and the cleaning product water return port 11.

[0034] In one possible implementation, the cleaning water tank 12 has an inspection port on the top, an vent 16 on the bottom, a level gauge port on the side and a level gauge installed on the side, a pH meter on the top, a stirring system inside, and a corrosion-resistant centrifugal pump 13 made of 316L stainless steel. The cleaning water tank 12 has a volume of 2-2.5 cubic meters and is used to prepare chemical cleaning solutions, such as acids, alkalis, and sodium hypochlorite, for cleaning ultrafiltration membranes after they become fouled. The inspection port facilitates internal inspection and maintenance. The drain port 16 at the bottom of the cleaning water tank 12 is equipped with a drain valve to facilitate the emptying and cleaning of the cleaning water tank 12. The level gauge at the level gauge port monitors the liquid level in the tank in real time. The cleaning water tank 12 has an overflow port at the top to prevent overflow caused by excessive liquid level. The water inlet of the cleaning water tank 12 is located at the top for adding cleaning solution or replenishing water. The stirring system ensures that the chemicals are completely dissolved.

[0035] One possible implementation also includes a solenoid valve box 15 and an electrical control cabinet 14. The solenoid valve box 15 is used to control the opening and closing of the first valve group, the second valve group, and the third valve group. The electrical control cabinet 14 is located on one side of the bottom of the skid-mounted structure 1, at the bottom of the solenoid valve box 15. The solenoid valve box 15 is used for centralized control of automatic valves. The material of the solenoid valve box 15 must meet at least the 304 stainless steel standard, and the protection level must meet at least the IP54 standard. The solenoid valve box 15 is designed with multiple solenoid valves inside to control the switching of various pipelines in the system. The solenoid valves are controlled by signals from the PLC controller in the electrical control cabinet 14 to realize pipeline switching under different operating conditions of the system. The solenoid valve box 15 is equipped with pressure gauges and flow meters inside to monitor system operating parameters. The solenoid valve box 15 is connected to various pipelines in the system through pipes 10 to form a complete control network.

[0036] Furthermore, the entire device of this utility model is 7500 mm long and 2300 mm wide, with a high degree of integration, facilitating hoisting and transportation. The skid-mounted structure 1 in the device adopts a steel skid structure with anti-corrosion surface treatment, possessing good strength and rigidity. The internal equipment, valves, instruments, pipelines 10, and cables are installed and debugged in the factory, with only external interfaces reserved, greatly reducing the amount of on-site engineering and labor intensity. The bottom of the device is equipped with a hoisting hole for easy overall hoisting and transportation. Maintenance access is provided around the device for easy equipment maintenance and operation.

[0037] The working process of this utility model is described below with reference to specific embodiments:

[0038] First, before starting the electrical control cabinet 14 and solenoid valve box 15, check the environmental safety and confirm the equipment status, including shutting off the main power supply and the air / liquid inlet valves. Next, open the electrical control cabinet 14 for internal inspection, ensuring there are no loose parts or burn marks, and wait for the capacitors to discharge. After powering on and initializing, check for no current / short circuit alarms. Test the motor load in manual mode to ensure correct start and emergency stop responses. Afterward, recheck the wiring and air circuit of the solenoid valve box 15 before startup, verifying the cables and air supply connections. After a single-unit jog test, switch to automatic mode and start the linkage to complete the startup process.

[0039] For first-time use, rinse the inside of pipe 10 with clean water, turn on the cleaning mode, and inject clean water into the cleaning water tank 12 through the inlet until the liquid level reaches 85% to 90% of the tank. Keep the water temperature at around room temperature, open the corresponding valve of pipe 10, start the cleaning water pump 13 and the circulating water pump 5, observe the system instruments, and adjust the pressure and flow rate to the rated values ​​to clean the pipe 10 throughout the device with clean water. Ensure that the pipe 10 system is unobstructed. Open the drain valve to purge the gas from pipe 10. Observe that no gas is discharged from the drain pipe, close the drain valve, and continue cleaning pipe 10 for no less than 30 minutes.

[0040] After cleaning, the cleaning mode is turned off, the working mode is started, the first valve group is opened, the first common pipe 3 is switched to the raw water inlet, and the circulating water pump 5 is started. Under the pressure drive of the circulating water pump 5, the raw water flows through the raw water inlet pipe to the tubular ultrafiltration membrane module 6. There is a transmembrane pressure difference inside the tubular ultrafiltration membrane module 6. The raw water passes through the membrane pores to form permeate, while suspended solids, colloids, bacteria, etc. are trapped on the inner side of the membrane to form concentrate. The permeate is output through the permeate outlet, and the concentrate is recovered or discharged through the concentrate return outlet. Some suspended solids accumulate on the inner surface of the membrane, causing the filtration load to gradually increase and the filtered water flow rate to decrease. When the system reaches the threshold, the ultrafiltration membrane module is cleaned immediately. The cleaning conditions are: the permeate flow rate decreases by 15% or more compared with the initial operating permeate flow rate; the transmembrane pressure difference increases by 0.05 MPa compared with the initial operating transmembrane pressure difference or reaches the value specified by the membrane manufacturer.

[0041] Perform the pre-rinse procedure, switch to the cleaning mode, inject room temperature clean water into the cleaning water tank 12 to 85% to 90% of the rated capacity, check and open the second valve group on the second pipeline, switch to the cleaning inlet function, close the first valve group on the first pipeline, start the cleaning water pump 13, flush the entire pipeline for 30 minutes to replace the water in the system, and after the flushing is completed, switch to the circulation cleaning.

[0042] Turn off cleaning water pump 13 and circulating water pump 5, then add clean water to the water tank to 50% level. Precisely control the water temperature at 30-40℃ and the cleaning pressure below 0.4MPa. Add cleaning agents to the water tank at a ratio of 2.5% of the clean water volume: 0.2%-0.5% hydrochloric acid, 1.0%-2.0% citric acid or oxalic acid solution, 0.2% sodium hypochlorite + 0.1% sodium hydroxide. Start the stirring system to ensure the agents are completely dissolved. Use an online pH meter to monitor the pH value of the cleaning solution in real time, and make the pH value of the cleaning solution reach 1-2. Perform acid washing first, followed by alkaline washing.

[0043] During the acid cleaning stage, the pH value should be controlled within the range of 1-2, while during the alkaline cleaning stage, the pH value should be controlled within the range of 11-12. The acid cleaning stage is used to circulate inorganic salt scale, and the circulation flow rate is adjusted according to the membrane module specifications. The cleaning time is 30 minutes. If the membrane surface is severely fouled, it can be extended to 2-24 hours and intermittent soaking can be used. In addition, after the acid cleaning stage is completed, the cleaning water tank 12 and pipe 10 should be emptied immediately and rinsed with clean water for 30 minutes. Then, alkaline cleaning is carried out to remove organic matter and biofilm contaminants. The circulation parameters are consistent with the acid cleaning, acid cleaning first and then alkaline cleaning. After the main cleaning stage is completed, rinse with clean water for 30 minutes until the pH value of the effluent is close to that of the influent.

[0044] The concentrated cleaning water generated during the cleaning process returns to the cleaning water tank 12 through the concentrated cleaning water return port for continued recycling, while the cleaning product water returns to the cleaning water tank 12 or is discharged through the cleaning product water return port 11.

[0045] After the cleaning process is completed, the cleaning effect is verified. Under standard operating conditions, the permeate flux of the membrane module is measured. The permeate flow rate is restored to 90% or more of the initial operating permeate flow rate, and the permeate pressure difference is not higher than 10% of the initial operating permeate pressure difference. The cleaning is considered effective when the color of the cleaning solution no longer changes, the pH value is stable for three consecutive times, or the pH value of the flushing water is stable. After the cleaning is completed, the system introduces clean water through the cleaning inlet to rinse and remove the residual cleaning solution. Then, it switches back to the working mode and enters the next operating cycle.

[0046] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A tubular ultrafiltration membrane device with an integrated cleaning system, characterized in that, include: Skid-mounted structure, cleaning water tank, cleaning water pump, circulating water pump, tubular ultrafiltration membrane module and piping assembly; The cleaning water tank is located at the bottom of the skid-mounted structure and is connected to the cleaning water pump. The cleaning water pump is connected to the circulating water pump and the circulating water pump is connected to the tubular ultrafiltration membrane module. The pipeline assembly is used to connect the cleaning water tank, the cleaning water pump, the circulating water pump, and the tubular ultrafiltration membrane module. The piping assembly includes a main inlet pipe, a first common pipe, a second common pipe, a product water pipe, and multiple pipes. The main inlet pipe is connected to the inlet of the circulating water pump. The first common pipe and the main inlet pipe are provided with a raw water inlet and a cleaning concentrate return outlet. The second common pipe and the main inlet pipe are provided with a cleaning inlet and a concentrate return outlet. The inlet of the product water pipe is connected to the outlet of the ultrafiltration membrane module. The outlet of the product water pipe is provided with a product water output outlet and a cleaning product water return outlet. The cleaning product water return outlet is connected to the cleaning water tank through a pipe. The multiple pipes are used to connect the main inlet pipe, the first common pipe, the second common pipe, the product water pipe, the cleaning water tank, the cleaning water pump, the circulating water pump, and the tubular ultrafiltration membrane module.

2. The tubular ultrafiltration membrane device of the integrated cleaning system as described in claim 1, characterized in that, The pipeline assembly also includes an overflow venting pipe, one end of which is connected to the outside and the other end is connected to the water production pipe.

3. The tubular ultrafiltration membrane device of the integrated cleaning system as described in claim 1, characterized in that, It also includes a first valve group, which is installed on the first common pipeline and is used to switch the functional state of the raw water inlet and the cleaning concentrate return outlet.

4. The tubular ultrafiltration membrane device of the integrated cleaning system as described in claim 1, characterized in that, It also includes a second valve assembly, which is installed in the second common pipeline and is used to switch the functional status of the cleaning inlet and the concentrate return outlet.

5. The tubular ultrafiltration membrane device of the integrated cleaning system as described in claim 1, characterized in that, It also includes a third valve group, which is installed in the water production pipeline and is used to switch the functional state of the water production outlet and the cleaning water return outlet.

6. The tubular ultrafiltration membrane device of the integrated cleaning system as described in claim 5, characterized in that, It also includes a solenoid valve box, which is used to control the opening and closing of the first valve group, the second valve group and the third valve group.

7. The tubular ultrafiltration membrane device of the integrated cleaning system as described in claim 6, characterized in that, It also includes an electrical control cabinet, which is located on one side of the bottom of the skid-mounted structure, at the bottom of the solenoid valve box.

8. The tubular ultrafiltration membrane device of the integrated cleaning system as described in claim 1, characterized in that, The cleaning water tank has an inspection port on the top, an vent at the bottom, a level gauge port on the side and a level gauge installed thereon, and a pH meter installed on the top of the cleaning water tank.

9. The tubular ultrafiltration membrane device of the integrated cleaning system as described in claim 1, characterized in that, The cleaning water tank is also equipped with a stirring system.

10. The tubular ultrafiltration membrane device of the integrated cleaning system as described in claim 1, characterized in that, The cleaning water pump is a corrosion-resistant centrifugal pump made of 316L stainless steel.

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