Patent ID: 8512568
Filing Date: 2013-08-20
Classification: B01D

Abstract:
1. A method for cleaning a membrane filtration module, the module comprising at least one membrane located in a feed-containing vessel, the membrane comprising a permeable wall, the method comprising: conducting a filtration operation wherein a feed is applied to a first side of the permeable wall and a filtrate is withdrawn from a second side of the permeable wall; suspending the filtration operation; performing a cleaning process on the permeable wall to dislodge a contaminant therefrom into a liquid surrounding the membrane; forming a gas-containing region on the first side of the permeable wall; sealing the feed-containing vessel; pressurizing a gas within the gas-containing region via a backwash operation; opening a lower valve of the feed-containing vessel to atmosphere when a pressure on the first side of the membrane equals a pressure on the second side of the membrane to generate an instantaneous negative transmembrane pressure, whereby the gas-containing region expands and produces a high velocity sweep of the feed-containing vessel to remove the liquid containing the dislodged contaminant through the lower valve; and suspending the backwash operation when the high velocity sweep of the feed-containing vessel is complete.