DE-SLUDGING SYSTEMS

摘要

Apparatus for periodically drawing accumulated sludge (12) from a settlement tank (10) includes a hydraulically powered ram type positive displacement pump (14), operation thereof being controlled automatically in a timed or other sequence in response to signals derived from a pressure transducer (34), conveniently in the hydraulic supply line (24), said signals being a function of the pressure exerted by the pump ram (22) in operation and hence the density or other properties of the material being handled by the pump, a higher pressure showing the presence of sludge and a lower pressure its absence.