Tight Gas Stimulation by In-Situ Nitrogen Generation

Abstract

Provided is a method and composition for the in-situ generation of synthetic sweet spots in tight-gas formations. The composition can include nitrogen generating compounds, which upon activation, react to generate heat and nitrogen gas. The method of using the composition includes injecting the composition into a tight-gas formation such that upon activation, heat and nitrogen gas are generated. Upon the generation of nitrogen gas and heat within the formation, microfractures are produced within the formation and the hydrostatic pressure within the reservoir is reduced to less than the reservoir fluid pressure, such that the rate of production of hydrocarbons from the formation is increased.

Description

RELATED APPLICATIONS[0001]This application claims priority to U.S. provisional application Ser. No. 61 / 563,233, filed Nov. 23, 2011, the disclosure of which is incorporated herein by reference in its entirety.FIELD OF THE INVENTION[0002]This invention relates to gas well stimulation and compositions for the stimulation of hydrocarbon reservoirs, including liquid and gas wells.BACKGROUND OF THE INVENTION[0003]The search for and recovery of oil is becoming increasingly difficult as world-wide petroleum reserves decline. In many instances, reserves trapped within certain low permeability formations, such as certain sand, carbonate, and / or shale formations, exhibit little or no production, and are thus economically undesirable to develop at current oil and gas prices. In certain unconventional formations, such as low permeability formations, the most important element that determines whether developing reservoir will be economically viable is finding sweet spots in the reservoir. It is ...

AI Technical Summary

Benefits of technology

[0010]In another aspect, a method for stimulating production of gas in a tight-gas formation, the method comprising the steps of injecting into the formation an aqueous solution that includes an ammonium containing compound and a nitrite containing compound, wherein at least one of the ammonium containing compound and the nitrite containing compound comprise a coating which is operable to prevent reaction therebetween; and then injecting an activator into the formation, the activator being capable of initiating reaction between the ammonium containing compound and the nitrite containing compound such that the reaction generates heat and nitrogen gas. Upon the generation of nitrogen gas and heat within the formation, microfractures are produced within the formation and the hydrostatic pressure within the reservoir is reduced to less than the reservoir fluid pressure, such that the rate of production of hydrocarbons from the formation is increased.

Problems solved by technology

The search for and recovery of oil is becoming increasingly difficult as world-wide petroleum reserves decline.

In many instances, reserves trapped within certain low permeability formations, such as certain sand, carbonate, and / or shale formations, exhibit little or no production, and are thus economically undesirable to develop at current oil and gas prices.

Unfortunately, current technologies are unable to locate or predict when and where sweet spots exist within a given formation.

In tight reservoirs, due to low permeability of the formation, well productivity is typically low, thus making the well non-economical from a standpoint of development.

These methods, however, have limited uses.

These techniques, however, typically use chemicals that require extensive procedures to ensure low environmental impact to the formation and surrounding area.

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