Abstract: To recover oil, including viscous oil, from an underground reservoir, a cyclic solvent-dominated recovery process may be used. A viscosity reducing solvent is injected, and oil and solvent are produced. Unlike steam-dominated recovery processes, solvent-dominated recovery processes cause viscous fingering which should be controlled. To control viscous fingering, operational synchronization is used within groups and not between adjacent groups.

Abstract: The invention provides an actuator for moving a threaded valve stem along a longitudinal axis to selectively open or close a valve. The actuator comprises a carrier rotatably mounted within a housing. A portion of the carrier has a bore threaded to receive the threaded valve stem. The actuator further comprises a gear arrangement configured for transmitting a rotational force to the carrier. A cylindrical operator rotatably mounted to the housing has a plurality of splines on its circumference and is configured for receiving a rotational input force from a drive mechanism. An annular collar slidably disposed around the operator rotates with the operator but can slide longitudinally along the operator between a first position in which it engages the gear arrangement and a second position in which it engages the carrier.

Abstract: The invention provides an actuator for moving a threaded valve stem along a longitudinal axis to selectively open or close a valve. The actuator comprises a carrier rotatably mounted within a housing. A portion of the carrier has a bore threaded to receive the threaded valve stem. The actuator further comprises a gear arrangement configured for transmitting a rotational force to the carrier. A cylindrical operator rotatably mounted to the housing has a plurality of splines on its circumference and is configured for receiving a rotational input force from a drive mechanism. An annular collar slidably disposed around the operator rotates with the operator but can slide longitudinally along the operator between a first position in which it engages the gear arrangement and a second position in which it engages the carrier.

Abstract: An economic method for in situ maturing and production of oil shale or other deep-lying, impermeable resources containing immobile hydrocarbons. Vertical fractures are created using horizontal or vertical wells. The same or other wells are used to inject pressurized fluids heated to less than approximately 370° C., and to return the cooled fluid for reheating and recycling. The heat transferred to the oil shale gradually matures the kerogen to oil and gas as the temperature in the shale is brought up, and also promotes permeability within the shale in the form of small fractures sufficient to allow the shale to flow into the well fractures where the product is collected commingled with the heating fluid and separated out before the heating fluid is recycled.

Abstract: Methods are provided that include the steps of providing wells in a formation, establishing one or more fractures (12) in the formation, such that each fracture intersects at least one of the wells (16, 18), placing electrically conductive material in the fractures, and generating electric current through the fractures and through the material such that sufficient heat (10) is generated by electrical resistivity within the material to pyrolyze organic matter in the formation into producible hydrocarbons.

Abstract: In a mining scheme, a mobile continuous haulage system follows a miner and transports material onto a floor mounted beltway. The beltway supports a roadway on which the haulage system is carried. The roadway has wheels captured in outboard rails on the beltway and lift cylinders on the roadway when lowered, raise the beltway off the floor so that the beltway can be advanced for a belt move to facilitate adding additional belt sections.

Abstract: A continuous mining machine is provided which includes a frame assembly having a material dislodging head mounted on one end of the frame. Ground engaging traction treads or wheels propel the machine within a mine to advance the dislodging head into a mine face to dislodge material therefrom. The mining machine also includes roof support apparatus capable of assuming a free-standing position separated from the mining machine to install supports in the roof above the mining machine as the mining machine continuously advances. The roof support apparatus includes a transverse beam having a pair of end portions extending outwardly from the sides of the frame assembly. Connected to the ends of the transverse beam are a pair of support assemblies each including apparatus for lifting the roof support apparatus vertically off the mining machine and initially supporting the mine roof.