In practical operations, ultrafiltration membranes often face two major technical challenges: first, fluctuations in influent water quality lead to instability in key parameters such as effluent resistivity and turbidity, making it impossible to meet the demands for high-purity water. Second, during long-term operations, ultrafiltration membrane modules are prone to clogging by impurities such as suspended solids and colloids in the influent water, resulting in reduced water flux and frequent cleaning, which significantly increases operational and maintenance costs. Based on practical experience, we offer the following solutions.

To address the challenge of water quality fluctuations, the core solution involves “pre-treatment adaptation + real-time monitoring and control.” First, based on the characteristics of the influent water entering theultrafiltration (UF) membranes, a pre-treatment module is installed upstream of the UF membrane modules. This module employs a combined process of quartz sand filtration and activated carbon adsorption to remove suspended solids, colloids, and some organic matter from the influent water in advance, thereby effectively reducing the treatment load on the UF membrane modules; Second, an online turbidity meter is installed to collect real-time data on both feed and effluent water quality. When feed turbidity exceeds 10 NTU or resistivity shows abnormal fluctuations, the system automatically adjusts the feed flow rate and chemical dosing to ensure stable influent water quality for the UF membrane modules and prevent effluent parameters from exceeding standards.

To address the issue of membrane fouling, a dual-pronged approach combining “tiered cleaning” and “anti-fouling optimization” is implemented. During routine operation and maintenance, a periodic backwash program is preset. Based on operating time, an air-water backwash is initiated to use gas to flush the surface of the UF membranes, reducing the accumulation of impurities. When the water flux of the UF membranes drops to 50% of the initial value, or when the feed water pressure and concentrate pressure increase significantly, a chemical cleaning process is initiated to thoroughly remove stubborn contaminants from the surface of the UF membranes.

Establish a standardized routine inspection mechanism to check the sealing performance and piping connections of  PVDF UF membrane modules on a weekly basis, and promptly replace aged seals to prevent fluctuations in water quality caused by water or air leaks. Conduct comprehensive performance tests on the UF membrane modules on a quarterly basis, and promptly repair or replace any membranes that fail to meet the standards for water permeability or retention rate, thereby ensuring the long-term stable operation of the equipment and meeting the requirements of various high-precision water applications.