Sand and gravel filters and centrifugal separation systems are offered for use on cooling tower or chilled water systems requiring large capacity, heavy-duty suspended solids removal.

     Filters are shipped complete with: tank; valve      manifold; gauges; initial charge of sand and gravel.

   The system switches valves automatically. Two backwash control mechanisms are available. Backwash cycles can be based on a time cycle (SG-250A) or pressure differential across the unit SG-250P. Filters must be installed in a bypass line so that plugging of the filter or temporary shutdown required for backwashing does not hinder process operation. The Centri-Separator System (CSS-150) is designed to handle up to 150-ton (453,600 Kcal/hr) tower systems. The CSS-150 includes centrifugal separator, 1/3 hp (0.25 kW) pump, 1/2” PVC electrically activated ball valve, and a 115 volt single-phase 60 hertz control station. The CSS-150 can be mounted on a pump tank or piped in a bypass line. The system performs all operations, including separator purging, automatically. The CSS-400 has been designed for larger tower water system applications. BF Series bag filters can be used in full flow or bypass configurations. A bypass configuration is recommended for chilled water systems.

Sand and Gravel Automatic Backwash Filters

    SG-250A sand and gravel automatic backwash filters are available in 250-ton (756,000 Kcal/hr) tower (Model SG-250A) and 500-ton (1,512,000 Kcal/hr) chiller (Model SG250P) maximum capacity. Please specify when ordering.

    Model SG-250A is equipped with automatic valves operated from a time device so that backwash is accomplished periodically on an automatic basis.

   Model SG-250P. Automatic valves are operated from pressure switch. Pressure switch monitors the pressure drop in the filter media and activates backwash cycle at preset pressure drop.