| 摘要 |
A manhole for purifying sewage in a river is provided to cut down sewage treatment expenses, and to prevent the river contamination by connecting a sewer pipe to a reservoir tank with a septic tank and draining sewage into a sewage disposal plant after first purifying in the septic tank and the reservoir tank. A manhole(10) includes a reservoir tank having a body(21) in which a fitting edge(25) is protruded and a cover(23) opening and closing the body for restricting inflow of foreign matters, a septic tank(30) installed in the reservoir tank to filter sewage from an inlet of the body and provided with a fitting projection(30a) inserted to the fitting edge of the body, and a bellows tube(40) connected to the inlet of the body and a sewer pipe(1) to communicate the sewer pipe with the inlet of the body. A sand filter tank embedding sand, an active carbon treatment tank and a filter removing floating matters are arranged in the septic tank. Sewage is purified from the sewer pipe through the sand filter tank, the active carbon treatment tank and the filter to the reservoir tank, and drained to a sewage disposal plant. |
