NOVELTY - Conversion of excrements into methane comprises constructing a sedimentation basin (4) at the sewage (2) corresponding to the waste pipe (1) of an apartment building, setting a filtering net (3) at the downstream of sedimentation basin, constructing a methane tank for fermentation (10), installing downward sloping connecting pipe (6) for sedimentation basin and methane tank, setting a sealing gate (5) on connecting pipe, setting methane tank, feed pipe (12) and hydraulic pressure chamber (11) underground, and conveying methane to the user in residential building through an air duct (9).    USE - Conversion of excrement into methane for residential use (claimed).    ADVANTAGE - The method is simple, easily operated, low investment and has good effect. The method not only solves the problem on people's unwillingness to process excrements and air pollution but also saves an amount of life expenditure for inhabitants, lowers the cost of sewerage treatment and city pollution discharge, and improves resources utilization ratio.    DETAILED DESCRIPTION - Conversion of excrements into methane comprises:    (A) constructing a sedimentation basin (4) at the sewage (2) corresponding to the waste pipe (1) of an apartment building;    (B) setting a filtering net (3) at the downstream of sedimentation basin to make the sewage flow automatically while filtering and concentrating the excrements in the sedimentation basin;    (C) constructing a methane tank (10) underground near the sedimentation basin;    (D) installing a downward sloping connecting pipe (6) between the sedimentation basin and methane tank;    (E) setting a sealing gate (5) on the connecting pipe which can be lifted on time through a handle (7) to let the excrements automatically flow into the methane tank for fermenting;    (F) setting all methane tank, feed pipe (12) and hydraulic pressure chamber (11) underground; and    (G) conveying the methane to the user in the residential building through an air duct (9).    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic sectional view of a sewerage treatment unit converting excrements into methane.    Waste pipe (1)    Sewage (2)    Filtering net (3)    Sedimentation basin (4)    Sealing gate (5)    Connecting pipe (6)    Handle (7)    Air duct (9)    Methane tank (10)    Hydraulic pressure chamber (11)    Feed pipe (12)