Abstract: A flow back separator including a housing including a bore housing for communicating with a solid collection chamber, an inlet port for receiving formation fluid flow, and a helical member disposed within the housing bore for directing formation fluid flow received through the inlet port along a helical path wherein solids within the formation fluid flow are forced towards a wall of the housing bore under centrifugal force.

Abstract: A rheological test apparatus and method using a helical screw rheometer. The screw in the rheometer is driven by a hydraulic motor controlled by a proportioning valve. A pressure transducer provides a pressure signal at the outlet of the rheometer, and a solenoid valve is used to close the outlet downstream from the pressure transducer. In a test, fluid is flowed into the rheometer. With the screw stopped and the discharge closed, a static pressure is measured by the pressure transducer, and a computer means resets this to a zero reference value. The screw in the rheometer is then rotated at a constant speed with the discharge closed, and the dynamic pressure at the outlet is measured by the pressure transducer. Because the static pressure was zeroed, the dynamic pressure value is substantially equal to the differential pressure across the rheometer. The test is repeated for different speeds.