Method and system for treating domestic sewage by artificial wet field

An artificial wetland sewage processing method and system belongs to processing of sewage and sludge, can solve problems of present artificial wetland biological film obstruction and short life. Excavating a pool body which filling with sandy soil and planting plant, an influent non-return valve is arranged under the pool body, sewage enters the pool body via the valve and permeates upward, a shoalbank ecosystem containing a biological film is composed of a root system, sandy soil and sewage, which purifies sewage through the biological film. A hard shell formed by the biological film is poured automatically, softened and sank by a L pipe, goes together with sewage scum through an erected scum pipe and a scum non-return valve in thereof, scum is sucked out by pressure difference generated by machinery or manmade. The non-return valve is automatically opened/closed by overflow of the L pipe. The L pipe also can conveniently provide fecal sewage for peasant to water farmland. In order to prevent generating thick biogas in the shoalbank ecosystem to cause explosion, a silo and a movable cover are arranged, people may enter and detect to guarantee safe operation. The invention is fit for domestic sewage treatment.