Core Working Principle

The tube wall of each hollow fiber UF membrane is densely covered with micron-scale pores to realize solid-liquid separation via physical sieving without chemical dosing. Driven by water pressure, raw water flows either outside-in or inside-out through the fiber bundles. Water molecules, dissolved ions and small molecular substances smaller than the pore size penetrate the membrane wall to form product water. Large particles including sediment, colloids, algae, bacteria, ova and high-molecular pollutants are trapped on the membrane surface and discharged out of the system via regular blowdown, backwashing and chemical cleaning, ensuring stable effluent quality and long service life of membrane elements.

Main System Components

• Hollow Fiber Membrane Module

The heart of the system, assembled with tens of thousands of bundled hollow capillary fiber filaments, available in two mainstream types: outside-in and inside-out configurations. Membrane materials commonly include PVDF, PAN, PES and PVC, featuring outstanding oxidation resistance, acid & alkali tolerance, strong fouling resistance and high mechanical strength, adaptable to diverse raw water conditions.

• Pipeline & Valve Assembly

Consists of raw water pipelines, product water pipelines, concentrate drainage pipelines and cleaning pipelines, equipped with manual, pneumatic or electric valves to freely switch working modes of water intake, water production, blowdown, backwashing and chemical cleaning.

• Pressurization & Power Equipment

Matched with booster pumps, backwash pumps and chemical dosing metering pumps to provide stable pressure and flow rate for filtration, back flushing and chemical circulation cleaning.

• Automatic Control & Protection System

Integrated with PLC control cabinet, pressure transmitters, flow meters, level switches and differential pressure monitors. It real-timely tracks transmembrane pressure difference, product water flow and operating pressure, with functions of auto start-stop, scheduled backwashing, differential pressure alarming and overload protection, enabling fully unattended automatic operation.

• Auxiliary Pretreatment Unit

Normally fitted with fine filters and security filters to block large particulate contaminants, preventing mechanical scratch damage to fiber filaments and extending the service life of UF membranes.

Operating Modes

• Normal Filtration

Pressurized raw water enters the membrane module to produce qualified purified water, while concentrated water is continuously drained or partially recirculated.

• Combined Air-Water Backwashing

Compressed air together with clean water reversely scours the membrane surface to strip trapped contaminants and mitigate membrane fouling.

• On-Line Chemical Cleaning

Sodium hypochlorite, acidic or alkaline detergents are circulated to remove persistent organic and biological fouling and restore membrane flux.

• Off-Line Chemical Cleaning

When membrane flux declines after long-term operation, the membrane module is disassembled for deep immersion cleaning for performance recovery.

Key Product Advantages

• Stable filtration accuracy and excellent effluent quality; over 99% of bacteria, suspended solids and colloids can be reliably removed.
• Operates at ambient temperature and low pressure with low power consumption; no phase change occurs, so the original physical and chemical properties of water remain intact.
• High fiber packing density leads to small equipment footprint; modular design facilitates capacity expansion, disassembly and routine maintenance.
• Strong anti-shock loading capacity tolerates raw water quality fluctuations; simple operation and high automation level.
• Long service life with excellent flux recovery after cleaning and low operation & maintenance costs, suitable for long-term continuous industrial operation.

Main Application Fields

• Municipal tap water quality upgrading and centralized rural water supply projects
• Industrial water treatment: pretreatment for purified / ultrapure water, circulating water filtration, boiler makeup water purification
• Wastewater treatment: advanced treatment and reclaimed water reuse for domestic sewage and industrial wastewater
• Special industries: water purification for food & beverage, pharmaceutical and aquaculture sectors; electrophoretic paint recovery, material concentration and separation

Operation Precautions

Membrane fouling degree is judged by transmembrane pressure difference, so the backwash cycle shall be strictly set according to actual working conditions. The influent shall be rigorously controlled for large particles and oil content. Regular chemical cleaning shall be scheduled according to water quality to avoid fiber blockage, aging and filament breakage, guaranteeing long-term stable and efficient system operation.