Patent ID: 8778193

Claim:
A method for the separation of liquid from a three phase slurry bubble column, comprising the steps of: a) applying a filtering pressure differential across a filtering media of a hollow and enclosed filter element and any filter cake build-up on an outside of said hollow filter element, to obtain and withdraw a filtrate from inside the hollow filter element, wherein there is no direct liquid communication between the inside of the hollow and enclosed element and the outside of the hollow and enclosed filter element except for passage of fluids through the filtering media; b) in parallel or followed by; charging, through at least one conduit configured for inflow of a rinsing fluid, the inside of the hollow and enclosed filter element with the rinsing fluid to clean the inside of the hollow and enclosed filter element of catalyst fines, wherein a charging pressure of the rinsing fluid when charging the inside of the hollow and enclosed filter element is equal to or lower than a pressure on the outside of the hollow filter element, in a slurry phase; thereafter c) removing the rinsing liquid together with any fines suspended therein from the inside of the hollow and enclosed filter element via a conduit configured for outflow of the rinsing fluid from an internal volume of the hollow and enclosed filter element; and thereafter d) applying a backwashing pressure differential opposite to the filtering pressure differential to force a backflushing fluid in an opposite direction across the hollow filtering media to dislodge filter cake build-up.