A new process was developed at the Kemper IGCC plant to filter ultrafine particles from water used in gasification processes. By using flocculation sedimentation with membrane filtration, over 99% of suspended solids were removed, and filtration rates increased tenfold compared to standard methods. A four-step sedimentation process removed 90-95% of solids before membrane filtration, producing clear water. The process involved adding polymers to the water, using static mixers for mixing, and a cleaning technique with sodium hypochlorite for regenerating filter media. The filtration process reached a maximum flow rate of 842 gpm, with the ability to handle higher flow rates.