A process for continuously extracting oil from a
solid or liquid oil-bearing material comprises (a) removing air from the extraction
system, (b) introducing an
inert gas into the extraction
system at a pressure sufficient to maintain a normally gaseous
solvent in
liquid state, (c) introducing an oil-bearing material into a
silo, (d) passing the oil-bearing material from the to a jet pump mixing device, (e) introducing a liquified normally gaseous
solvent into the jet pump mixing device, (f) mixing the oil-bearing material and the
solvent in the jet pump mixing device for a time sufficient to permit complete
wetting of oil-bearing material by the solvent to form a mixture, (g) heating the mixture to near supercritical conditions; (h) passing the mixture through an extractor having a
screw conveyor adapted to rotate at a first rpm range and a centrifugal drum adapted to rotate at a second rpm range, (i) treating the mixture within the extractor in such a manner that supercritical
temperature and pressure are attained, wherein treating the mixture includes a combination of increasing the rpms of the centrifugal drum, increasing the temperature inside the extractor and increasing the
inert gas pressure inside the extractor, (j) extracting oil from the mixture by
pressure diffusion provided by the combination of increased rpms, increased temperatures and increased
inert gas pressures at supercritical conditions, (j) removing liquids extracted from the mixture through a liquids exit port, and (k) removing solids extracted from the mixture through a solids exit port.