Ultrafiltration (UF) is a low-pressure filtration process in which the components of a liquid are separated through the pores of a semi-permeable membrane based on their unique molecular sizes.

UF is used in a variety of process water and wastewater treatment applications. For example, ultrafilters are used to clarify liquids such as fruit juice, corn sweeteners and brackish water. UF is also used in the dairy industry to concentrate milk protein and in all automobile assembly plants to recover and reuse water-based electrode position paint.

FII UF systems effectively separate oil, grease, heavy metals and suspended solids from wastewater using FII-manufactured ultrafiltration modules. Water and low molecular weight solutes (e.g., salts and some surfactants) are removed as permeate, while emulsified oil and suspended solids remain in the process stream and are removed as concentrate.

Filter Innovations supplies a full range of standard UF systems that can be customized for high performance in virtually any industrial wastewater treatment or recovery application.

Advantages of Ultrafiltration

Consistent Permeate Quality
Ultrafiltration is a closed system, and no major hourly or daily variation in discharge of permeate will occur. Variations in feed may result in productivity changes, but permeate quality will not be compromised.

Permeate Quality

• Suspended solids: <10 mg/L
• Oil and grease: <50 ppm
• Metals (Mn, Pb, Cu, Ni, Cr, Fe): typically <1 ppm
  • Up to 99% rejection under pH control

Reproducible Performance
Membrane systems are designed for long-term operation, offering long membrane life and predictable daily productivity.

Low Operation and Maintenance Costs
Membrane systems require minimal manpower, and costs associated with membrane systems are competitive with chemical or physical treatment costs.

Ability to Recycle
Ultrafiltration systems often permit the reuse of process water, mop water, coolants and cleaners.

Advantages of Ultrafiltration in Industrial Settings

Many industrial processes generate oily wastewater, and disposal of this wastewater into the sewage system is generally not permitted. When this is the case, a waste generator has two choices: pay a waste disposal company to pick up and dispose of the waste, or treat the wastewater on site and either reuse or recycle the treated water.

In addition to the high cost of disposal services, on-site water treatment is preferential for two reasons:

Cradle to Grave Responsibility
The waste generator's liability does not end when the waste disposal company assumes possession of the wastewater. Since the generator may be held liable if the waste is not processed and disposed of properly, many firms wish to minimize their exposure to such undefined and unlimited liability. This may be accomplished by gaining control of, and responsibility for, the treatment process.

Recycling Capability
The current trend in industry is towards greater recycling and resource utilization. By treating wastewater on site, valuable constituents of the waste may be recovered for reuse. The water itself may even be treated to the point of being acceptable for reuse in the manufacturing operation. For many types of oily wastewater, on-site treatment using membrane filtration is the most effective and lowest cost technology.