Lost prime - vacuum filtrate pump

[IronMike]

Vacuum filtrate receiver pump occasionally pumps receiver empty and loses its prime when level control fails. Pump is about 10 feet below bottom of receiver. An old filter manual says that receivers can be fitted with an added connection for centrifugal pumps to prevent loss of prime. However, no details provided. Does anybody know how this would work?

 

[25362]

I think one possibility would be by connecting the pump's volute highest point to the filtrate receiver via an automatic priming valve.

 

[IronMike]

Thank you for the response. We already have level controls in the receivers that don't work very well and the pumps frequently lose prime. A strictly hydraulic solution would be very attractive. Seems like the balance line would have to be much smaller than the process lines to avoid recirculating too much back to the receivers. Would a larger section of discharge pipe work as well by holding volume equal to or more than pump casing when suction is lost?