A process and system for recovering hydrocarbonaceous products from in situ oil shale formations. A hole is drilled in the oil shale formation and a processing gas inlet conduit is positioned within the hole. A processing gas is pressurized, heated, and introduced through the processing gas inlet conduit and into the hole. The processing gas creates a nonburning thermal energy front within the oil shale formation so as to convert kerogen in the oil shale to hydrocarbonaceous products. The products are withdrawn with the processing gas through an effluent gas conduit positioned around the opening of the hole, and are then transferred to a condenser wherein a liquid fraction of the products is formed and separated from a gaseous fraction.
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.degree. 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.
