Ultrafiltration
Removing Microscopic Contaminants While Preserving Essential Minerals
What is Ultrafiltration?
Bacteria and Pyrogen Removal
Effectively eliminates most bacteria, pyrogens, and colloids from the water.
Mineral Retention
Keeps beneficial minerals in the water while filtering out harmful contaminants.
Non-Electric Operation
Uses regular water pressure to push water through the filter, no electricity required.
Chemical-Free
Does not involve any chemicals, making it safe for consumption.
Ultrafiltration (UF) is a membrane filtration process where water is forced through a semipermeable membrane under hydrostatic pressure. This process retains larger suspended solids and high molecular weight substances while allowing water and smaller solutes to pass through. UF employs a hollow fiber membrane that traps contaminants inside each fiber. The effectiveness of UF depends on the size of the contaminants it can filter out.
How Ultrafiltration Works
For optimal Ultrafiltration (UF), the membrane pores should be between 0.01 and 1.0 microns in size. This allows the UF membrane to filter out particles that are up to 5,000 times smaller than a human hair. In Singapore, where water pressure typically exceeds 2 bar (50 psi), UF membranes can effectively remove contaminants. UF is ideal for eliminating colloids, proteins, bacteria, pyrogens, and large molecules. High-quality UF membranes can remove most bacteria, a significant amount of viruses, and parasites while retaining essential minerals.
Types of Filtration: Particle Filtration, Microfiltration (MF), Ultrafiltration (UF), and Reverse Osmosis (RO)
Here’s a comparison of the four most common water filtration methods:
Particle Filtration
1 to 20 μm
Microfiltration (MF)
1 to 0.1 μm
Ultrafiltration (UF)
0.1 to 0.001 μm
Reverse Osmosis (RO)
0.001 to 0.0001 μm
The key difference between these methods is their pore size. UF and RO are effective for removing bacteria and viruses, but UF only partially removes minerals, whereas RO removes them completely. RO-filtered water is often more acidic compared to UF-filtered water due to the lack of minerals. Therefore, RO-filtered water may require remineralization to restore its balance.
In Singapore, since chlorine is used to disinfect the water, there are no significant levels of bacteria or viruses, which reduces the need for RO. Thus, Puriwell Global uses UF as the third stage in our filtration system, providing a final level of protection against potential contaminants. Particle and MF filters are used as the first line of defense to eliminate larger particles and lessen the load on the UF filter.
How Often Should You Replace the Ultrafiltration (UF) Filter?
It is recommended to replace the UF filter every 9 to 12 months. However, this can vary based on factors such as the filter material, the condition of the water pipes, and the water source. To extend the life of the UF membrane, installing a Particle Filter or MF before the UF filter is advised.
How Often should I Change the Ultrafiltration (UF) Filter?
The recommended duration is every 9-12 months but the exact duration is highly dependent on various factors like material used, age of the water pipe and water source. To prolong the UF membrane filter, it is suggested to have either Particle Filtration or MF installed before UF.