Description

The filtration process is designed to remove suspended and floating particles from water by passing it through a porous bed, typically composed of sand and gravel. The main body or vessel is constructed from steel sheets according to technical specifications and recognized standards to suit various working conditions. It features two inspection ports, fluid inlet and outlet connections, and a steel plate (collector). The water distribution network for inlet, outlet, backwashing, feeding, and draining is installed along with all required fittings before and after the sand filters. To properly backwash the filters, the system must include at least two sand filter units. The incoming water is evenly distributed across the silica surface by a water distributor located at the top of the filter. Clean water is collected at the bottom by specialized nozzles appropriately arranged on the nozzle plate. Multiple layers of crystalline silica media with 98% purity, varying in thickness and particle size based on the physical properties of the water, are arranged sequentially over a perforated steel plate to perform the filtration. The vessels must be equipped with a backwash system, including a timer for wash cycle scheduling, drain and inspection valves, and air release valves. For automatic backwashing, special hydraulic valves should be used. Since each backwashing cycle requires the filter to be refilled, automatic air release valves must be included to prevent air entrapment, which can cause pressure drop and reduced flow rate. These air release valves help avoid corrosion and cavitation phenomena in the system.