Pressurised liq. filter subsequently clears residual liq. - by spare elements, held inactive by valves during main operation

摘要

Liq. is filtered under pressure while flowing radially inwards through tubular elements enclosed in individual casings. Filtrate discharges via valved outlets into a common header. During normal filtration, the valves controlling discharge in outlet and header cut off the discharge flow from one or more filter units, pref. near the edge of the assembly. In this period, liq. is delivered from a base outlet in a by-pass route, with a pump discharging liq. into the channel formed by an inclined collar plate below the pump discharge. A vertical weir in the channel ensures a free gap remains between collar and filter element. After cake build up terminates normal filtration, header valve is closed and outlet valves opened, enabling unused filters now to be used for residual liq. in the system. The valves may be manually or automatically controlled. ADVANTAGE - No separate filter is needed, as with known systems, for residual liq. after the main operation.