Ultrafiltration membrane

In today's water treatment field, ultrafiltration (UF) technology is gaining popularity due to its efficiency, cost-effectiveness, and versatility. Ultrafiltration technology, through its unique filtration principles, not only significantly improves water quality but also effectively reduces operational costs. Let's delve into the working principles of ultrafiltration technology and its advantages in water treatment. What is Ultrafiltration Technology? Basic Principle: Ultrafiltration membrane is a filtration technology that utilizes a semipermeable membrane to physically separate substances. The pore size of ultrafiltration membranes typically ranges from 0.01 to 0.1 microns, effectively removing suspended particles, bacteria, and viruses, while allowing water and dissolved salts to pass through. Advantages of Improving Water Quality Efficient Removal of Pollutants: Ultrafiltration membranes can effectively remove most suspended solids, bacteria, and viruses, thereby improving water quality. This results in clean water suitable for various applications such as drinking water, industrial purified water, and other high-quality water demands. Retention of Beneficial Minerals: Unlike reverse osmosis, ultrafiltration technology does not remove beneficial minerals from water. This ensures that essential nutrients remain in the water, which is crucial, especially for drinking water applications. Enhanced System Reliability: Ultrafiltration systems are highly effective in removing microorganisms and suspended solids, reducing the load on downstream equipment. This enhances the overall reliability and efficiency of the entire water treatment system. Advantages of Reducing Operating Costs Reduced Chemical Usage: Due to the effective removal of suspended solids and pathogens, ultrafiltration membranes often require fewer or no chemicals for treatment. This reduces chemical procurement and handling costs, as well as minimizes environmental impact. Lower Energy Consumption: Ultrafiltration systems typically operate at lower pressures compared to other high-pressure filtration systems like reverse osmosis. This directly reduces daily operational energy costs. Lower Maintenance Costs: Ultrafiltration membranes have longer cleaning and replacement cycles, making maintenance relatively straightforward. This reduces downtime and maintenance expenses, further lowering operational costs. Extended Equipment Lifespan: Effective pretreatment by ultrafiltration technology protects subsequent treatment equipment, prolonging the overall lifespan of the water treatment system. This reduces equipment replacement frequency and related costs. Application Examples Municipal Drinking Water Treatment: Ultrafiltration technology is widely used in municipal drinking water treatment to remove bacteria and suspended solids, ensuring safe water supply for residents. It preserves minerals in water, enhancing water taste and quality. Industrial Wastewater Treatment: Ultrafiltration technology excels in industrial wastewater treatment, particularly in pretreatment stages, effectively removing suspended solids and oils. This protects downstream treatment equipment and reduces overall treatment costs. Seawater Desalination Pretreatment: In seawater desalination processes, ultrafiltration serves as a crucial pretreatment step by removing most suspended particles and microorganisms. This reduces the burden on reverse osmosis systems, prolongs membrane lifespan, and lowers overall operational costs. Through ultrafiltration technology, not only can water quality be significantly enhanced but operational costs can also be effectively reduced. Whether it's municipal drinking water treatment, industrial wastewater treatment, or seawater desalination, ultrafiltration technology demonstrates unique advantages and promising applications. If you have further interest or inquiries about ultrafiltration technology, please feel free to contact us.

A Key Technology in Efficient Water Treatment Ultrafiltration membranes (UF) are at the core of modern water treatment technologies, widely recognized for their high filtration efficiency, broad applications, and cost-effectiveness. Their uses span municipal water supply to industrial wastewater treatment, providing reliable solutions for different water purification needs. In this blog, we will explore the key advantages of ultrafiltration membranes and how they excel in water treatment. 1. High-Precision Filtration Ultrafiltration membranes typically have pore sizes ranging from 0.01 to 0.1 microns, making them highly effective in removing suspended particles, bacteria, viruses, colloids, and large organic molecules from water. This allows for high-precision filtration in various applications, such as in drinking water purification, where ultrafiltration ensures the removal of pathogens while retaining beneficial minerals in the water. 2. Low Operating Pressure and Energy Consumption Compared to other membrane separation technologies (such as reverse osmosis membranes), ultrafiltration membranes operate at lower pressures, meaning they require less energy. This lower energy consumption can result in significant cost savings during extended operations, which is particularly important for industries requiring large volumes of water treatment. 3. Excellent Chemical Stability Ultrafiltration membranes are typically made from materials that are resistant to chemical corrosion, such as polyvinylidene fluoride (PVDF) and polyethersulfone (PES). This allows them to be used in a wide range of water treatment environments, adapting to different water qualities and chemical compositions. Whether treating acidic, alkaline, or wastewater containing organic solvents, ultrafiltration membranes maintain stable performance. 4. High Throughput and Easy Cleaning Ultrafiltration membranes offer high water throughput, meaning they can process large volumes of water with the same membrane surface area. Additionally, ultrafiltration systems are typically equipped with automatic backwashing functions that periodically clean the membrane surface, extending the membrane's lifespan and reducing maintenance costs. This self-cleaning ability ensures long-term, stable system operation. 5. Broad Application Scenarios Due to their high-efficiency separation and stable performance, ultrafiltration membranes are widely used across various industries: Municipal water supply: Ultrafiltration membranes remove microorganisms and suspended solids to ensure safe drinking water. Industrial wastewater treatment: They are effective in treating various industrial wastewaters, especially in removing suspended solids and large organic contaminants. Food and beverage industry: Ultrafiltration is used for the concentration and purification of products like juices and milk, ensuring high-quality standards. Pharmaceutical and biotechnology: Ultrafiltration membranes perform well in separating biological macromolecules and proteins.

1. Overview During the long-term operation of the ultrafiltration device, the impurities in the water will accumulate over time, and the separation performance of the membrane is gradually affected. Therefore, the ultrafiltration device needs to chemical clean the membrane components regularly and irregularly to restore the performance of the membrane. Compared with normal operation, the water production of the ultrafiltration system decreases by more than 10%~20% or the transmembrane pressure difference increases by 0.08~0.1MPa (the transmembrane pressure difference shall not exceed 0.2MPa at any time), and the membrane flux cannot be restored by backwashing, the ultrafiltration system should be cleaned chemically. Chemical cleaning is using a certain concentration of specific chemical agents in the membrane system for circulation and soak, to clean the dirt on the surface of the membrane wire. Chemical agents are selected according to the type of water quality and the pollution characteristics of the membrane components. 2. Selection of chemical cleaning agents (1) Alkali washing: 0.2% sodium hypochlorite (according to the effective chlorine meter) + 0.1% sodium hydroxide solution, that is, the ratio of 10% sodium hypochlorite solution adding 20L and 1kg sodium hydroxide solid per 1 ton of water. Scope of application: when the organic content in the water is high, it may cause the filter membrane to be organic matter pollution. And when the conditions are conducive to biological survival, some bacteria and algae will also multiply in the ultrafiltration membrane components, resulting in biological contamination.     (2) pickling: 1~2% citric acid solution or 0.2% hydrochloric acid solution, that is, the ratio of 7kg of industrial hydrochloric acid or 10~20kg of citric acid per ton of water. Scope of application: when the content of Fe, Mn or other metals in the inlet water exceeds the design standard, or the suspended matter in the inlet water of ultrafiltration membrane components is particularly high, and the non-organic pollution caused to the inlet side of the membrane. 3. Specification table of common agents Table 1 Specification table of common agents for chemical cleaning name specifications Active substance content Clean the use concentration Sodium Hypochloride (NaClO) 25KG / barrel Effective chlorine concentration of 8 to 10% 0.1~0.5% (as active chlorine meter) Sodium hydroxide (NaOH) 25KG / package 99% 0.1~0.2% Industrial hydrochloric acid (HCl) 25KG / package 26%~30% 0.1~0.5% citric acid 25KG / barrel 99% 1~2% 4. Flow chart of chemical cleaning   Figure 1 Flow chart of ultrafiltration chemical cleaning 5. Cleaning steps A. Close the ultrafiltration device according to the shutdown procedure, and close all the valves on the device; B. Prepare the acid / base solution in the cleaning solution box and stir well to mix well;C. Open the cleaning water inlet valve (V03) and the cleaning fluid return valve (V04, V05), and then start the cleaning pump.Allow the wash solution into the membrane assembly and return to the wash solution chamber. The cycle cleaning time is60min-120min； D. Close the cleaning pump, set the static soak, the time depends on the pollution situation, generally more than 60min; E. Wash in recirculation for 10-20min; F. Backwash and forward wash of the ultrafiltration device alternately until the drainage PH value of the ultrafiltration device is neutral; G. Continue the second agent cleaning or return to the production run state.