Abstract: In filters of the type in which a cake of solids deposited from a liquid slurry thereof on a generally horizontal filter medium is subjected to treatment involving passage of liquid through the cake while on the filter medium, means is provided for increasing the drainage rate of the formed cake by causing the cake to form on the medium from the slurry fed thereto by gravity settling in the liquor of the slurry and by removing liquor of the slurry from above the cake while the liquor still contains unsettled fine particles.

Abstract: In filters of the type in which a cake of solids deposited from a liquid slurry thereof on a generally horizontal filter medium is subjected to treatment involving passage of liquid through the cake while on the filter medium, means is provided for increasing the drainage rate of the formed cake by causing the cake to form on the medium from the slurry fed thereto by gravity settling in the liquor of the slurry and by removing liquor of the slurry from above the cake while the liquor still contains unsettled fine particles, such means including means providing a backflushing flow of liquid through the underside of the filter medium and the cake forming thereon into the slurry.