Patent ID: 8683858

Claim:
A recirculating, constant backpressure apparatus for flooding a core with at least one chosen fluid, comprising: a core holder for containing said core and having a longitudinal axis, an inlet port for introducing the at least one fluid into contact with said core, an outlet port, and a port for applying a chosen pressure to an exterior surface of said core; an overburden pressure pump in fluid connection with the pressure port of said core holder; at least one fluid pump for pumping the at least one chosen fluid in fluid communication with the inlet port of said core holder; a separator for separating the at least one fluid from said at least one fluid pump by density thereof from other fluids exiting the core holder after having passed through said core, said separator having a first bottom port, a second bottom port, and at least one fluid return port for returning fluid to said at least one fluid pump; a backpressure pump in fluid communication with the outlet port of said core holder for maintaining a chosen back pressure at the outlet port of said core holder, and in fluid communication with the first bottom port of said separator for transferring the at least one fluid exiting said core holder to said separator; and a pressure compensation pump in fluid communication with the second bottom port of said separator for preventing a change in pressure as the at least one fluid is transferred to said separator by said back-pressure pump.