Laying structure for vacuum sewer pipe of vacuum sewage collecting system.

摘要

A laying structure for a vacuum sewer pipe of a vacuum sewage collecting system for collecting sewage discharged from homes and facilities into a collecting tank through a vacuum sewer pipe kept negative in pressure internally is disclosed. The vacuum sewer pipe includes a portion laid in a plain topography which comprises a downward pitch portion sloped toward downstream, and a short upward pitch portion connected to the downstream end of the downward pitch portion to return a depth of the vacuum sewer pipe to an original level, the downward pitch portion and the upward pitch portion are alternated at least once. The upward pitch portion starts from a spot deepened from the original laying level by a depth corresponding to 0.8 to 1.0 times of a bore of the vacuum sewer pipe. By this arrangement, an air lock is not produced at the upward pitch portion even if the quantity of air flowing in the vacuum sewer pipe is low.