Electro-osmotic production of hydrocarbons utilizing conduction heating

Abstract

An electro-osmotic method for the production of hydrocarbons utilizes in situ heating of earth formations having substantial electrical conductivity. A particular volume of an earth formation is bounded with a waveguide structure formed of respective rows of discrete elongated electrodes in a dense array wherein the active electrode area and the row separation are chosen in reference to the deposit thickness to avoid heating barren layers. Electrical power is applied at no more than a relatively low frequency between respective rows of electrodes to deliver power to the formation while producing relatively uniform heating thereof and limiting the relative loss of heat to adjacent regions to less than a predetermined amount. At the same time the temperature of the electrodes is controlled near the vaporization point of water to maintain an electrically conductive path between the electrodes and the formation. A heat sink is provided by supplying aqueous liquid electrolyte to space between the electrodes and the adjacent formation, thereby maintaining the temperature thereat no greater than about the boiling point of water and maintaining a conductive path between said formation. A d.c. polarized potential is applied to enhance flow of reservoir fluid into a preselected row of electrodes, and collected reservoir fluids are removed from the electrodes in the preselected row.