Problems Deserving of Attention in Designing Siphon Filter Air Water Washing Process Chen Zhongzheng;Cheng XiaoruThis paper has analysed the cause of mudballs forming in the filter bed, it also proposes a newprocess varying water washing to air water washing with moving air supply device to remove mud-balls\Based on the test results, opinions of the process design are given.Siphon filter;;Dirt;;Air water washing process