Membrane filtration is a technology that undertakes physical separation process using pressure. Although the technology has been commercially available more than 30 years ago, it is not ordinarily used in potable water treatment practices.

The first commercial membrane system was built in the mid-1980s with the purpose to recover the high value, niche product such as wine, juices and water for pharmaceutical in view of its relatively high cost. Similarly in Malaysia, membrane filtration was first introduced by the commercial and manufacturing sector such as beverage, electronics and pharmaceuticals, whereby high quality or pure water is required for their products. The treatment plant is normally installed in their own premises with the raw water source obtained from the municipal water supply. The membrane filtration was used to further polished the water by means of desalting, softening and removal of dissolved organics, colour causing compound and fine particle.

However, membrane filtration is now fast becoming a common technology used to treat potable drinking water in developed countries and is also rapidly gaining acceptance throughout the world as an effective and economical water treatment method. The application continues to grow, as the membranes are now increasingly cost effective with better performance characteristics.

Furthermore, with the ever-increasing load of a variety of pollutants in our surface water such as endocrine disrupting chemicals, eco-hazard, carcinogens etc, and also the ever-increasing demand for high water quality by the consumers, the use of membrane filtration technology is expected to become popular and will be the future water treatment technology.

The system is now widely used in many developed parts of the world like USA, Europe, Japan, Middle East for potable water treatment including our neighbouring country, Singapore for desalting and NEWater production. In potable water industry in Malaysia, Perbadanan Bekalan Air Pulau Pinang Sdn Bhd has started to use the system as a pilot project at its 5 MLD Bukit Panchor WTP in the mid of 2006.

There are many benefits in using membrane filtration for potable water production when compared to the conventional treatment method as listed below:

• The Membrane Filtration system is reliable to consistently produce very high quality and crystal clear filtered water. This is achievable as the pore size of the membrane filtration media is very small, in the range of microns instead of millimetres or centimetres.
• Membrane Filtration is able to remove suspended solids without the need to use chemicals. With less chemical consumption, the associated health risks that are always related to chemical use in water treatment process such as aluminium is eliminated.
• The chemical-free waste arising from non-useable of chemicals in the treatment process will not pollute the environment and can be discharged directly to local water bodies and waterways without further treatment.
• Membrane filtration can remove microorganisms in water such as protozoa, bacteria and viruses as the pore size of the membrane is very much smaller than these microorganisms. In fact, it can effectively and completely remove chlorine-resistant pathogenic protozoan cysts and oocysts of Cryptosporidium and Giardia. The effective removal of these microorganisms makes the water very safe for consumption.
• The chemical consumption required for disinfection especially chlorine will be substantially reduced as most of the microorganism will be removed at the filtration stage.
• The membrane filtration water treatment system is of modular design and compact. Thus, it will require small footprint and does not require large space, which will lead to cheaper development cost if built in land-starved urban areas. Furthermore, it can be easily expanded corresponding to the water supply demand.
• The system can be easily integrated into simple automation and remote control system and makes its operation simple.