Method, apparatus and composition to increase recovery of hydrocarbons by reaction of selective oxidizers and fuels in the subterranean environment

Abstract

A method, apparatus and composition are described for safe energy delivery down hole resulting in increased recovery of subterranean hydrocarbons. The method utilizes the reaction of non-alkane fuels and selective oxidizers which are non-selective toward alkane chemical compounds. The energy released in the subterranean reaction is utilized to heat the wellbore, the formation or the formation hydrocarbons thereby lowering fluid viscosity and permitting greater flow especially for heavy oils. Further, safe delivery of oxidizers can be accomplished without limit on depth as the selective oxidizer may be delivered to point of use down hole as most all formations of interest contain primarily alkane hydrocarbons and will not react with the non-alkane selective oxidizer. In addition some products of reaction may be insoluble in water and can be utilized for fluid loss prevention, flow diversion, abrasive drilling and or as proppants.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority to U.S. Provisional Patent Application No. 61 / 795,016, filed Oct. 9, 2012 entitled, “Method, Apparatus and Composition to Increase Recovery of Hydrocarbons by Selective Oxidation of Fuels in the Subterranean Environment” and the disclosure of which are incorporated herein by reference.TECHNICAL FIELD[0002]Embodiments of the present invention are generally directed toward enhanced oil and gas production by means of the thermal stimulation of formation hydrocarbons in situ or in the wellbore during production.BACKGROUND ART[0003]It is well known in the oil and gas industry that production from oil wells will increase upon heating the oil and thereby lower the viscosity of that oil. This is especially true for the more viscous heavy oil and tar sand deposits where incremental changes in temperature can lead to an order of magnitude change in viscosity. To date there have been but a few successful thermal meth...

AI Technical Summary

Benefits of technology

This patent is about a new way to increase the production of oil from underground oil layers. This is done by using special chemicals called selective oxidizers that are introduced into the oil layer through a wellbore. These chemicals react with certain molecules in the oil layer to release energy that can help to get the oil out of the layer. The special thing about these chemicals is that they are not harmful to the oil or the environment, making the process safer and more efficient. Additionally, the chemicals can be used at much greater depths in the oil layer, making the process even more effective.

Problems solved by technology

Although the fire flooding method has produced very desirable results in some cases it suffers from two main problems.

The first of which is safety related in that the oxygen utilized can be an unwanted fire and explosive hazard when combined with natural gas either at the injection well or at the production well.

Another issue with fire flooding technology is the use of a gaseous oxidizer in which the compressor horse power requirements and available installed well casing place a depth limit of utilizations to shallower formations.

Hence, a significant resource remains out of technical reach.

In addition there are at present electrical bottom hole heaters which are also restricted to fairly shallow depths and suffer from a major heat transfer defect in that the produced flow takes the heat away from bottom hole where it is needed (Prats, M., 1985.

The primary of these hazards being that oxygen is produced by decomposing the hydrogen peroxide from which if the system is improperly operated may form a combustion / explosive mixture with methane either down hole or in the production lines.

While the intention would be to consume all of this oxygen an explosion hazard is still present and must be accounted for.

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