Detritus separator associated with sand and grit trap used on wastewater treatment plant, has rearwardly-descending drainage shaft

摘要

From the base (4) of the waste water passage (1) a waste drainage shaft (5) descends, inclined against the direction of flow in the passage. With the passage connected to a grit catcher chamber (2), water is recirculated by a pump around the circuit comprising passage, drainage shaft (5) and grit chamber. The drainage shaft discharges into the grit catcher. The drainage shaft is connected to an extraction screw (17). The waste shaft has a known form of actuated valve, which is opened to extract the detritus separated. This includes a cover which is spring-loaded to open. It is operated by fluid pressure in an expansion bellows, which acts against the spring. An opening connects fluid from the waste shaft into the bellows.