Abstract: The process for obtaining oil, gas and other products from pyrobituminous shales and the like includes introducing crushed shale into a retort and contacting the crushed shale in the top portion of the retort with a stream of retort gases. Hot gases are injected at an intermediate point of the retort and a stream of cold gases are injected at the bottom of the retort. The gaseous retorted matter above the zone where the shale undergoes pyrolysis is removed and directed to a cyclone from separation of heavy liquid components from a gaseous stream. The gaseous stream is then purified and compressed with a portion of the compressed stream being heated and reinjected as the steam of hot gases into the retort. The other portion of the compressed stream of gases is cooled and a liquid component consisting primarily of water and heavy oil is separate therefrom in a spray tower.

Abstract: An improved filling and discharge valve for use with a hydraulic cylinder is provided, the valve comprising a valve body having a first chamber therein supporting a spring-biased main valve piston having an extending portion containing a chamber in which a second spring-biased valve is supported, the valves operationally being interdependent and being capable of being coupled to a hydraulic cylinder so as to control the flow of oil from oil-storage means to said hydraulic cylinder and back to said oil-storage means according to a pre-determined working cycle. Control valves and switches are provided to control the operation of the filling and discharge valve.