Treatment of subterranean formations
AssigneeInnospec Limited
InventorsIan Malcolm McRobbie, William Trenholme
Life of this patent
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Abstract
A method of treating a subterranean formation by contacting the formation with the following (a) ammonium bicarbonate; (b) and oxidizing agent selected from a perchlorate or a nitrite or combinations thereof; and (c) an acid (AA).
Claims23
1-34. (canceled)
A method of treating a subterranean formation, the method comprising contacting the formation with the following:
- (a) ammonium bicarbonate;
- (b) an oxidizing agent selected from a perchlorate or a nitrite or combinations thereof;
- and
- (c) an acid (AA).
A method of treating a subterranean formation, the method comprising contacting the formation with the following:
- (a) ammonium bicarbonate;
- (b) an oxidizing agent which is sodium nitrite;
- (c) an acid (AA) selected from sulfamic acid and ammonium bisulfate;
- and mixtures of sulfamic acid and ammonium bisulfate;
- wherein a ratio (A) defined as the number of moles of ammonium bicarbonate divided by the number of moles of nitrite contacted with the formation and/or reacted in the formation is in the range 0.3 to 0.6;
- wherein a ratio (E) defined as the number of moles of ammonium bicarbonate divided by the sum of the number of moles of sulfamic acid and ammonium bisulfate contacted with the formation is greater than 0 and is 10 or less;
- and
- wherein a ratio (K) defined as the number of moles of nitrite divided by the sum of the number of moles of sulfamic acid and ammonium bisulfate which are arranged to react with materials contacted with the formation, to produce a gas is in the range 0.1 to 10.
A method of treating a subterranean formation to create or enhance a fracture in the formation, the method comprising contacting the formation with the following:
- (a) ammonium bicarbonate;
- (b) an oxidizing agent which is sodium nitrite;
- (c) an acid (AA) selected from sulfamic acid and ammonium bisulfate;
- and
- mixtures of sulfamic acid and ammonium bisulfate;
- wherein a ratio (A) defined as the number of moles of ammonium bicarbonate divided by the number of moles of nitrite contacted with the formation and/or reacted in the formation is in the range 0.3 to 0.6;
- wherein a ratio (E) defined as the number of moles of ammonium bicarbonate divided by the sum of the number of moles of sulfamic acid and ammonium bisulfate contacted with the formation is in the range 0.3 to 0.6;
- wherein a ratio (K) defined as the number of moles of nitrite divided by the sum of the number of moles of sulfamic acid and ammonium bisulfate which are arranged to react with materials contacted with the formation, to produce a gas is in the range 3 to 1.7;
- wherein in the method the sum of the wt % of a formulation (F1) comprising said ammonium bicarbonate, a formulation (F2) comprising said nitrite, and a formulation (F3) comprising an or said acid (AA) introduced into the formation is at least 98 wt % of the total weight of materials introduced into the formation as part of the fracturing of the formation by production of gas within the formation;
- wherein the method includes introducing proppant and/or microproppant into the formation to enter fractures formed in the method.
Dependencies are inferred from the claim text.