Colloidal silica, typically found in surface waters, is a complex with organic matter that creates problems in high pressure boiler operations. Particulate silica (sand particles) can be removed by conventional pre-treatment and reactive silica (ionized) can be removed by ion exchange and/or reverse osmosis (RO). Colloidal or polymerized silica however can only partly be removed by conventional treatment methods. The presence of silica in boiler feed water is harmful as it gets deposited as glassy and hard scales on the turbine blades. These silica deposits seriously affect the plant performance and can even lead to turbine failure.
HFS 60 Silica is a robust tight ultrafiltration membrane that can offer a true alternative in silica removal from surface water as it offers the most reliable protection for boilers and turbines. The silica removal rate is 10 times better than standard ultrafiltration, no coagulant is needed and the membranes can be used in the process as pre-treatment instead of polishing. By reducing the colloidal silica, the boiler efficiency is maximized and the number of plant shutdowns is reduced significantly.