Abstract: A self-cleaning return pump system for use with a clean-in-place system for cleaning vessels includes a recirculation loop for providing flow communication including a return pump, an eductor, and a separator. The return pump is arranged to discharge a liquid through the eductor into the separator and is supplied with a substantially continuous flow of liquid from the separator. A return line provides flow communication between the vessel to be cleaned and a suction port of the eductor. The separator has a top discharge port and a bottom discharge port. The top discharge port is configured to discharge a liquid or a liquid-air mixture therefrom to the clean-in-place system. The return pump causes liquid flowing through the recirculation loop at the eductor to have sufficient dynamic head to draw liquid or a mixture of liquid and air from the vessel through the return line, into the eductor. The liquid or liquid air mixture is discharged into the separator.

Abstract: Improvements are disclosed in a rotary, lobar, positive-displacement pump and in a rotary, centrifugal pump, whereby all product-contacting areas of the pumps can be effectively cleaned without disassembly, i.e., cleaned in place. Non-rotating seals seal the impellers and isolate the pump shafts from the product zone. Each seal has an elastomeric member molded integrally thereto. The seal is biased by the elastomeric member so as to be slidably pressed against an impeller. In the lobar pump, certain passageways can be selectively closed and opened, so as to adapt the pump for being used to pump a pumpable material when closed and for being cleaned by a cleaning solution flowing therethrough when opened. Valves may be alternatively provided for analogous purposes.