Patent ID: 7686964

Claim:
A method for dewatering and washing a lime mud before dewatered lime mud is transported to a lime mud kiln, comprising: dewatering the lime mud in a pressurized filter, connecting the pressurized filter to a closed gas circulation system, connecting a filtrate tank to a filtrate side of the pressurized filter and where a fluid level of filtrate is established from the pressurized filter, pressurizing the pressurized filter, a compressor drawing on a suction side thereof a gas phase from the filtrate tank, and a pressurized side of the compressor pressurizing, via the gas circulation system, a lime mud side of the pressurized filter, venting a pre-determined amount of the gas phase directly from the gas circulation system, and adding an equivalent pre-determined amount of fresh air directly to the gas circulation system to maintaining a partial pressure of oxygen gas above a pre-determined minimum level.