DILUTION CENTRIFUGING OF BITUMEN FROTH FROM THE HOT WATER PROCESS FOR TAR SAND

摘要

In the known operation wherein naphtha-diluted bitumen froth is pumped from a scroll-type centrifugal separator to a disc-type centrifugal separator, an improved pumping system is provided. The system comprises at least two centrifugal pumps in series, each operating at less than 65% of design capacity. The invention is based on the discovery that dilution with naphtha greatly increases the emulsification tendency of the froth components; therefore it is necessary to reduce shearing of this stream to keep the solids and water content of the disc product within a desirable limit. This is achieved by using staged pumps and operating the pumps at a relatively low tip speed.