Ultrafiltration (UF) equipment is a precision filtration system designed and manufactured by our company, utilizing ultrafiltration membranes as the core separation medium. Under pressure, this product physically screens water particles through the micropores on the membrane surface (typically 0.01-0.1 microns), effectively retaining colloids, bacteria, viruses, macromolecular organic compounds, and suspended solids while allowing water molecules and small-molecule solutes to pass through. As a membrane separation technology bridging traditional filtration and nanofiltration, it provides a solution for liquid clarification, separation, purification, and concentration.
- Structure and Working Principle
- Core structural composition
A complete ultrafiltration system is typically designed in a modular configuration, with core components including:
- Ultrafiltration membrane module: the core separation unit. Based on membrane materials, it can be classified into polyvinylidene fluoride (PVDF), polyethersulfone (PES), polyacrylonitrile (PAN), etc.; based on configuration, it can be categorized into hollow fiber, spiral-wound, and plate-and-frame types, among which the hollow fiber type is widely used in water treatment.
- Pressure vessel and frame: designed to house and secure membrane modules, with integrated piping and instrumentation.
- Circulation and filtration system: includes the feed pump, circulation pump and related valves, providing the power and flow state required for filtration and cross-flow operation.
- Backwash and chemical cleaning system (CIP/CEB): A critical maintenance unit comprising a backwash tank, backwash pump, and chemical dosing system, designed to periodically restore membrane flux.
- The automation system integrates PLC, flow, pressure and water quality instruments to achieve automatic filtration, backwashing, cleaning and protection.
- Working Principle
Under pressure, raw water flows across the ultrafiltration membrane in either continuous flow or cross-flow filtration mode. The pressure differential forces water and solutes smaller than the membrane pores to pass through, yielding permeate (filtrate), while larger particles are retained. After prolonged operation, periodic automatic backwashing and air scrubbing remove retained substances from the membrane surface to restore its performance. When the transmembrane pressure differential exceeds the set threshold, the system initiates either Chemical Enhanced Backwashing (CEB) or Continuous Ion Exchange (CIP) to eliminate irreversible fouling.
- High-precision physical screening: The membrane exhibits uniform pore size distribution, enabling stable retention of substances with molecular weights ranging from thousands to hundreds of thousands of daltons. It demonstrates significant efficacy in removing turbidity, bacteria (>99.99%), and viruses.
- The produced water exhibits excellent and stable quality: its turbidity typically remains consistently low, unaffected by short-term fluctuations in raw water quality, thus providing high-quality feedwater for subsequent treatment processes such as reverse osmosis.
- Operating at room temperature and low pressure, it features relatively low energy consumption: the working pressure typically ranges from 0.1 to 0.3 MPa, significantly lower than reverse osmosis, and requires neither heating nor phase change, resulting in distinct operational energy characteristics.
- High degree of automation with relatively convenient maintenance: The PLC controls fully automated operation, including timed backwashing, air scrubbing, and chemical cleaning. The membrane modules are standardized components, facilitating easy replacement.
- Extensive material compatibility: Membranes of various materials can be selected based on material properties (e.g., pH, temperature, solvent compatibility) to meet diverse separation requirements.
- Main Technical Parameters
|
Parameter item
|
Description / Reference Range
|
|
Membrane pore size/retention molecular weight
|
Pore size: 0.01 – 0.1 μm; Retention molecular weight: 5,000 – 150,000 Daltons
|
|
membrane area of single membrane module
|
Common range by model: 20 – 80 square meters
|
|
design flux
|
Strongly correlated with water quality and temperature, the empirical range for surface water is 40– 80 LMH (liters per square meter per hour).
|
|
working pressure
|
0.05 – 0.30 MPa
|
|
percent recovery
|
Full-flow filtration mode: 90–98%; cross-flow filtration mode: slightly lower
|
|
backwash interval
|
30–60 minutes, each session lasting 1–2 minutes
|
|
chemical cleaning cycle
|
Depending on the pollution level, it usually takes 1 to 3 months.
|
|
filament material
|
PVDF, PES, PAN, etc. are available as options, with PVDF being more widely used due to its chemical stability and anti-contamination properties.
|
- Typical Application Fields
Ultrafiltration equipment is suitable for various scenarios requiring high-precision solid-liquid separation or macromolecular substance separation:
- Deep purification of drinking water: the core treatment unit for municipal waterworks upgrading and residential direct drinking water systems.
- Pre-treatment of industrial water supply: Provides high-quality feedwater with low SDI (Sulfate Dissolved Index) for reverse osmosis (RO) and electrodialysis (EDI) systems, protecting the precision membrane elements downstream.
- Wastewater Treatment and Reuse:
- Advanced treatment and reuse of municipal sewage and industrial wastewater (e.g., electroplating, textile).
- The core membrane separation unit of the membrane bioreactor (MBR) process.
- Food and Biopharmaceuticals: Juice clarification, enzyme preparation concentration and separation, fermentation broth sterilization, pharmaceutical water pretreatment.
- Other fields: seawater desalination pretreatment, oilfield reinjection water treatment, landscape water purification.
en
