Closed loop heating and cooling water systems can contain high levels of suspended solids, these solids can be in the form of large particulate such as sealing tape, swarf, soil, brick dust and pebbles and various construction materials down to very small particulate and biological matter. This particulate can range in size from >5mm to below 5 micron and can cause damage to system components such as pumps, valves and heat exchangers. This is where side stream filtration is effective.
Side-Stream filtration is an effective method of removing these solids without system interference from the filter system itself. As the filter is connected in side-stream not all the heating water flowing through the system is filtered at the same time and as such the side stream filter can be a relatively small unit which in turn keeps capital cost to a minimum.
The Velocitek OVF (optimum velocity filter) system is a self cleaning filtration system which provides filtration down to a grade of below 1 micron nominally. The Velocitek OVF filter system can be connected in side stream to provide effective side stream filtration to heating and cooling water system for the removal of suspended solids to avoid system damage. The Velocitek OVF filter connected as a side-stream filter is manufactured from stainless steel and can be supplied suitable for operating pressures up to 10 bar and temperatures up to 90 degrees C.
The picture of water samples opposite show samples taken from a system water of a heating water system with the Velocitek OVF self cleaning filter connected as a side stream filtration system. (LHS filter inlet water, middle filter outlet water, filter backwash – solids removed by filter)