Abstract: A series of specialty formulations of foaming mud cement are injected into an underground cavity containing an active coal fire. The fire is smothered and terminated with a blanket of foaming mud cement that sets into a cellular concrete. The lower section of the backfill involves a formulation of foaming mud cement containing materials conducive to heat transfer, thus forming a heat sink for dispersion of elevated temperature associated with the fire. The backfill continues to complete cavity fill using a formulation of foaming mud cement wherein the aggregate is composed of hazardous waste materials that are permanently stored within the cellular concrete.

Abstract: Production of methane from an underground wet coal seam is initiated by drilling a well from the surface of the earth through the seam. Rather than pumping water to lower hydraulic head on the seam to permit desorption of methane within the coal, high pressure gas is injected into the seam to drive water away from the wellbore. Gas injection is terminated and the well is opened to flow. Initial gas production is return of injected gas, followed by a mixture of return injected gas and methane, followed by free methane from the fracture system of the coal, and then by methane desorbed from the coal. Upon return of displaced water to the wellbore, pumping operations remove water at rates that permit sustained production of desorbed methane.

Abstract: After a linkage channel is established through an underground coal seam connecting two vertical wells, a tubing bender/straightener is positioned in a first well aligned with the linkage channel. Oxidizer injection tubing is inserted from the wellhead into the tubing bender/straightener. The tubing is forced through the tubing bender/straightener and on into the linkage channel. The coal is ignited and the fire sustained by continuous injection of oxidizer through the tubing, creating a reaction zone separated from the first well with products of reaction recovered through the second well.

Abstract: Coal is reduced to ash in place by gasification using in situ production techniques, resulting in significant void space underground, which in turn causes roof fall and subsidence. Overburden collapse is stabilized by backfilling with foaming mud cement that hardens into an expanded solid, which quenches and fills the production module and seals residual ash. Rubble volumes and subsidence cracks are sealed against water incursions and contaminated water excursions. Surface facilities above barrier pillars are protected from destructive forces of subsidence draw.

Abstract: Coal is reduced to ash in place by gasification using in situ production techniques, resulting in significant void space underground, which in turn causes roof fall and subsidence. Overburden collapse is stabilized by backfilling with foaming mud cement that hardens into an expanded solid, which quenches and fills the production module and seals residual ash. Rubble volumes and subsidence cracks are sealed against water incursions and contaminated water excursions. Surface facilities above barrier pillars are protected from destructive forces of subsidence draw.

Abstract: Coal is reduced to ash in place by gasification using in situ production techniques, resulting in significant void space underground, which in turn causes roof fall and subsidence. Overburden collapse is stabilized by backfilling with foaming mud cement that hardens into an expanded solid, which quenches and fills the production module and seals residual ash. Rubble volumes and subsidence cracks are sealed against water incursions and contaminated water excursions. Surface facilities above barrier pillars are protected from destructive forces of subsidence draw.

Abstract: Coal is reduced to ash in place by gasification using in situ production techniques, resulting in significant void space underground, which in turn causes roof fall and subsidence. Overburden collapse is stabilized by backfilling with foaming mud cement that hardens into an expanded solid, which quenches and fills the production module and seals residual ash. Rubble volumes and subsidence cracks are sealed against water incursions and contaminated water excursions. Surface facilities above barrier pillars are protected from destructive forces of subsidence draw.

Abstract: In a dipping underground petroleum reservoir devoid of a natural gas cap, a mixture of gases soluble in petroleum is injected into a well positioned in an up dip location. Gases in the mixture are selected for their diverse solubility and diffusion characteristics. Gas injection is terminated followed by attic oil production wherein the gases accompanying the produced oil are separated and measured. The separated gases are then compared quantitatively with gases injected and the solubility capabilities of the produced oil. Results are used to estimate the size of the attic portion of the reservoir. Alternating cycles of gas injection and attic oil production are continued until the well is engulfed by the expanding artificial gas cap.

Abstract: Heavy oil from underground oil sands or tar sands is liquified with recirculation of superheated water and when brought to the ground surface is then wet oxidized for its heat value. The sulphur content of the products of wet oxidation is then wet reduced to elemental sulphur for by-product. The carbon dioxide gas generated as a product of wet oxidation is injected back to wells for its value as a diluter of the oil. Heat produced from wet oxidation is used for useful work at wells site.

Abstract: Hydrogen is injected into an underground petroleum reservoir that is devoid of natural gas. Due to its high rate of diffusion, hydrogen disperses rapidly throughout the reservoir, including the tight portions that are relatively impermeable to the injection of water. Pressure is lowered in the reservoir when the crude oil is substantially saturated with hydrogen. Hydrogen then migrates from the tight portions of the reservoir, sweeping petroleum into the more permeable portions. Expanding hydrogen experiences a temperature rise which in turn heats the crude oil and further reduces the viscosity for added mobility. A water sweep displaces the oil to production wells. In an alternate embodiment hydrogen is injected into an underground petroleum reservoir as a prelude to fire flood techniques. The absorbed hydrogen dilutes the crude in place and provides a fuel with much wider flammability limits to sustain the underground fire.

Abstract: A reactor vessel is established wherein a fuel is oxidized within an inert oxygen-carrier liquid. A portion of the heat of oxidation is used to raise steam. In one embodiment a double acting engine is interconnected to the reactor vessel wherein the first stroke of the piston is actuated by exhaust gases from the products of oxidation and the return stroke of the piston is actuated by the said steam. In other embodiments generated gases are used to power a turbine and a gas lift pump.

Abstract: Reactor pressure vessel with reactant fluid injectors for forming a liquid environment of an oxygen carrier fluid, sulphur and water in the presence of a catalyst to yield sulphuric acid and heat exchangers to capture generated heat.

Abstract: Hydrogen and other gases that are miscible in petroleum are injected into an underground reservoir to the extent that the volume of hydrogen exceeds the absorption capacity of the petroleum, thereby forming a gas cap composed substantially of hydrogen. Petroleum is withdrawn from the reservoir in part under the influence of gases absorbed into the petroleum and in part under the influence of increased reservoir pressure created by an artificial gas cap. Reservoir temperature is increased by establishing a combustion zone within the underground petroleum reservoir. Hydrogen is withdrawn from the artificial gas cap and is reinjected into the petroleum adjacent to the combustion zone with the resultant hydrogenation of the petroleum.

Abstract: Stack gases derived from combustion of hydrocarbons are scrubbed by direct contact with an inert liquid capable of taking sulphur compounds into solution. The inert liquid pregnant with sulphur compounds is injected into a reactor where the sulphur compounds are converted into sulphurous acid or in the presence of a catalyst wet oxidized into sulphuric acid. Product acid is withdrawn from the reactor and the stripped inert liquid is returned to the scrubber to repeat the process. Waste heat is captured for further useful work.

Abstract: A method for the manufacture of sulphuric acid wherein sulphur, in one case, and a source of sulphur in another case is reacted at superatmospheric temperatures and pressures with oxygen dissolved in an inert liquid in the presence of water, the inert liquid being selected from fluorocarbon compounds having eight or more carbon atoms. Heat is captured from the inert liquid.

Abstract: Materials with unfulfilled chemical oxygen demand are oxidized in a liquid environment at superatmospheric temperatures and pressures. The liquid environment is created within a pressure vessel by an inert liquid that is capable of absorbing and dispersing oxygen. Generated heat is captured for further useful work.

Abstract: This invention relates to the use of superheated water as a heat carrier to melt or reduce the viscosity of a solid or semi-liquid hydrocarbon located in an underground deposit. Steam is injected in one conduit and water is injected in a second conduit. Steam is condensed and mixed with the injected water in an underground mixing chamber under sufficient pressure to maintain the resultant superheated water in the liquid phase.

Abstract: A Frasch process sulphur mine power plant is coupled to a steam-electric generating plant by a coupling heat exchange means, wherein the heat liberated by condensing steam is substantially used to bring Frasch mine water up to operating temperature.

Abstract: Heat carrier fluid is circulated through an underground deposit of immobile petroleum. Circulation patterns are provided for more uniform heat transfer. Petroleum is made flowable and is recovered at the surface of the ground. Excessive underground channeling is controlled. Sand accumulations are removed from the well bore.

Abstract: This invention relates to the recovery of petroleum from tar and heavy oil sands in which one or more injection passages and two or more removal passages are established between the surface of the ground and an underground petroleum deposit. Hot water is injected into the petroleum deposit at a temperature above the pour point temperature of the petroleum substance, and heat is transferred until the petroleum substance becomes flowable. Under the influence of induced pressure, the petroleum substance is made to flow countercurrent to the flow of heat, with the petroleum substance captured at the surface of the ground.