APPARATUS AND METHOD FOR SUPERCRITICAL FLUID EXTRACTION OR SUPERCRITICAL FLUID CHROMATOGRAPHY

摘要

A variable-orifice fluid restrictor (11) for use with a supercritical extractor or chromatograph includes an inlet line for fluid at a pressure above its critical pressure, an extended tubular probe having an inner and an outer surface and a proximal and a distal end. The proximal end of the probe is disposed toward the inlet line. The distal end of the probe includes an adjustable orifice means (1240) adapted for metering the fluid and having first and second orifice members and an adjusting stem having first and second ends. The adjustable orifice means (1240) is adjacent to the outer surface of the probe and the orifice means (1240) is adjustable with the adjusting stem. The end of the stem is located at the distal end of the probe and is adapted for moving the first orifice member with respect to the second orifice member to control the adjustable orifice (1240) for varying the restriction of the fluid passing through the adjustable orifice (1240).