Precoat filters are used to treat solutions having traces of insoluble contaminations. They embody a rigid, semi-flexible or flexible screen on which a filter is deposited medium. During the filtration process the filter medium and the filtrated solids form a filter bed, which works as an additional strainer element to collect much finer contaminants. The “bed” medium may filter by adsorption and by mechanical means. The filter vessel is filled with the suspension under pressure and it passes through the filter bed, leaving the solids in the filter bed. The purified water is then collected after the filter element.
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