A test was conduced to purify sewage from CAU with a modeling cylinder filled by artificial soil with 3 irrigating time and 4 ratios of wetting-drying. The result showed that a plan with short irrigating time and short dry time was beneficial to return infiltration function of infiltration bed, if there was a long irrigation time to be used during treatment, and long dry time correspond to it. It has been found that there were highest removal effects for COD, BOD 5, SS and TN of sewage in 4 seasons with 8 h...