Abstract: Underground viscous hydrocarbon deposits, such as the viscous residues in conventional oil wells, are heated by mechanical wave energy to fluidize the hydrocarbons thereby to facilitate extraction thereof. For uniform, circular, symmetrical dispersion of mechanical wave energy of high-power and low-frequency, a mechanical wave energy radiator is provided comprising a cylindrical elastic tube of springy steel or the like preferably dimpled or corrugated and closed at one end and containing a liquid medium. Mechanical wave energy is applied to the liquid medium by a reciprocating source or the like connected to the radiator by a rigid walled tubular pipe or the like. The axial length of the radiator tube should be an odd multiple of one-quarter wavelength of the mechanical wave energy transmitted. Cavitation within the liquid is avoided by biasing the system with a steady state pressure at least as great as the maximum negative pressure swing of the mechanical waves in the liquid.

Abstract: A method of extracting hydrocarbons, energy and other products in situ from an underground coal deposit. A selected part of the coal deposit is heated by electrical induction to temperatures high enough to effect the destructive distillation of coal. The gases and liquids so produced are collected. Next, air or oxygen is injected into the remaining deposit which consists primarily of coke in order to burn it in place. The hot combustion gases thereby yielded are led to the surface of the deposit to generate energy. Lastly, the heat remaining underground after the coke has been burned is extracted by injecting water or steam into the deposit. The resulting steam is conducted to the surface to drive a steam turbine. The electrical induction heating is conveniently effected by passing a selected time varying current through a conductive path encompassing that part of the coal deposit to be heated.

Abstract: A method of heating hydrocarbons in situ in an underground hydrocarbon deposit such as bituminous sands or oil shale. A selected part of the deposit is heated by electrical induction coils arranged in a quasi-toroidal configuration to temperatures high enough to facilitate extraction. The coils are preferably comprised of interrupted rectangular turns. A series of generally concentric quasi-toroidal configurations can be used to heat large volumes. A hexagonal honeycomb array of such configurations can be used to heat deposits underlying very large surface areas.

Abstract: A method of extracting hydrocarbons in situ from an underground hydrocarbon deposit such as oil shale. A selected part of the deposit is heated by one or more electrical induction coils arranged in a quasi-toroidal configuration to temperatures high enough to drive off hydrocarbon fractions as gases or vapors, which are then collected and utilized in surface operations or recovered for transportation or temporary storage. The deposit may optionally be heated through a coking and cracking stage. Any remaining hydrocarbons may be burned in situ and the combustion gases utilized for energy. Steam may be obtained by injecting water into the heated shale after extraction of the hydrocarbons.

Abstract: The electric induction heating in situ of a selected portion of an underground deposit of hydrocarbons (such as petroleum, especially petroleum entrapped within a sand formation or the like, or lignite), for the purpose of facilitating extraction of hydrocarbons from the deposit. The heating is conveniently effected by passing alternating current through a conductor encompassing the selected portion. The conductive path is preferably a toroid, helix, or simulated toroid or helix, created by drilling and passing one or more conductors through the drill holes.

Abstract: A method of extracting metal from an underground ore body. The body is heated by electric induction to a temperature sufficient to break up the metallic ore compound and liquefy the metal. The metal flows into production wells where it is collected and transported to the surface, as by rapid solidification into powder or pellets in a pressurized gas stream. The electric induction is conveniently effected by passing alternating current through a conductor encompassing that portion of the ore body to be heated.

Abstract: A method of extracting hydrocarbons in situ from an underground hydrocarbon deposit (such as petroleum or lignite). A selected part of the deposit is heated by electrical induction to temperatures high enough to drive off hydrocarbon fractions as gases or vapors, which are then collected. The deposit may be heated through a coking and cracking stage. The electrical induction heating is conveniently effected by passing alternating current through a conductive path encompassing that part of the deposit to be heated.