Patent ID: 8758622

Claim:
A method of cleaning a membrane in a membrane filtration system, the membrane filtration system including a membrane module having a drain valve, a feed inlet connected to the membrane module, a feed line having a pressure reducing device fluidly connected to the feed inlet, a source of gas fluidly connected to the pressure reducing device, and a check valve connected between the source of gas and the pressure reducing device, the method comprising: flowing a liquid through the feed line and the pressure reducing device; opening the drain valve to create a reduced pressure within the feed line and cause the check valve to open; allowing a flow of gas from the source of gas to flow into the liquid to produce a liquid and gas mixture; introducing the liquid and gas mixture into the membrane module; scouring a surface of the membrane with the liquid gas mixture; and flowing the gas from the source of gas into the liquid until an increase in resistance in the membrane increases the pressure within the feed line and causes the check valve to close and prevent flow of the gas from the source of gas.