Abstract: A method for heat injection into a subterranean formation is provided. The method utilizes flameless combustion and a gas fired heater having an electrical heated surface for ignition of the gas. The absence of a flame eliminates the flame as a radiant heat source and results in a more even temperature distribution throughout the length of the burner. Flameless combustion is accomplished by preheating the fuel and the combustion air to a temperature above the autoignition temperature of the mixture. Preheating hydrocarbon fuel requires the inclusion of a carbon formation suppressant such as carbon dioxide or steam to prevent carbon formation.

Abstract: A process to recover oil is provided wherein an oil containing subterranean formation is heated by conductive heat transfer. The high temperature levels of this process result in high recoveries of initial oil in place, and recovery of the oil within a short time period. This process is particularly applicable to diatomite formations that have low permeabilities.

Abstract: A process to recover oil is provided wherein an oil containing subterranean formation is heated by conductive heat transfer from heat injectors operating at temperatures above 900.degree. C. The high temperature levels of this process result in high recoveries of initial oil in place, and recovery of the oil within a short time period. This process is particularly applicable to diatomite formations that have low permeabilities.

Abstract: An apparatus and method are disclosed for producing thick tar sand deposits by preheating of thin, relatively highly conductive layers which are a small fraction of the total thickness of a tar sand deposit, with horizontal electrodes and steam stimulation. The preheating is continued until the viscosity of the tar in a thin preheated zone adjacent to the highly conductive layers is reduced sufficiently to allow steam injection into the tar sand deposit. The entire deposit is then produced by steam flooding.

Abstract: An apparatus and method are disclosed for producing thick tar sand deposits by electrically preheating paths of increased injectivity between an injector and producers, wherein the injector and producers are arranged in a triangular pattern with the injector located at the apex and the producers located on the base of the triangle. These paths of increased injectivity are then steam flooded to produce the hydrocarbons.

Abstract: An apparatus and method are disclosed for producing thick tar sand deposits by preheating of thin, relatively conductive layers which are a small fraction of the total thickness of a tar sand deposit, with horizontal electrodes. The preheating is continued until the viscosity of the tar in a thin preheated zone adjacent to the conductive layers is reduced sufficiently to allow steam injection into the tar sand deposit. The entire deposit is then produced by steam flooding.

Abstract: A method is disclosed for producing thick tar sand deposits by preheating of thin, relatively conductive layers which are a small fraction of the total thickness of a tar sand deposit. The thin conductive layers serve to confine the heating within the tar sands to a thin zone adjacent to the conductive layers even for large distances between rows of electrodes. The preheating is continued until the viscosity of the tar in a thin preheated zone adjacent to the conductive layers is reduced sufficiently to allow steam injection into the tar sand deposit. The entire deposit is then produced by steam flooding.

Abstract: Hot liquid-containing water-swollen tar is produced from a tar sand by injecting steam into a well, which is at least initially open and substantially free of obstruction to vertical fluid flow throughout a long vertical interval from the bottom of the tar sand, by producing said liquid from the bottom of the tar sand and maintaining injection and production flow rates that keep the steam temperature above about 450.degree. F. at a pressure high enough to keep the produced liquid substantially free of steam and near to, but less than high enough to damage the reservoir.