WELL TREATMENT METHODS
Provided herein are compositions and methods for treating wells in geologic formations. The method involves introducing a first aqueous composition containing an organic acid into a well, introducing a second aqueous composition into the well, and forming a third composition useful for stimulating wells, fracturing geologic formations, and cleaning wells of filter cakes and other well blockages.
1 . A method for treating a well in a geologic formation comprising:
a) introducing to the well a first composition comprising about 40 wt. % to about 99.5 wt. % of an acid selected from among an alkylsulfonic acid, an arylsulfonic acid, a phosphorous acid, an alkylphosphonic acid, an arylphosphonic acid, an alkyl carboxylic acid, an aryl carboxylic acid, and combinations thereof; and
b) introducing to the well a second composition comprising water,
wherein the first and second compositions combine in the well to form a third composition comprising about 20 wt. % to about 40 wt. % of the acid.
2 . The method of claim 1 , wherein the third composition increases flow of hydrocarbons from the geologic formation into the well.
3 . The method of claim 1 , wherein the geologic formation is a carbonate formation.
4 . The method of claim 3 , wherein the third composition creates wormholes in the carbonate formation.
5 . The method of claim 1 , wherein the geologic formation is a sandstone or shale formation.
6 . The method of claim 5 , wherein the third composition enhances the permeability of the sandstone or shale formation.
7 . The method of claim 1 , wherein the acid comprises an alkylsulfonic acid.
8 . The method of claim 7 , wherein the acid is methanesulfonic acid.
9 . The method of claim 1 , wherein the first composition comprises about 65 wt. % to about 80 wt. % of the acid.
10 . The method of claim 1 , wherein the first composition comprises about 68 wt. % to about 72 wt. % of the acid.
11 . The method of claim 10 , wherein the first composition comprises about 68 wt. % to about 72 wt. % methanesulfonic acid.
12 . The method of claim 1 , wherein the third composition comprises about 25 wt. % to about 40 wt. % of the acid.
13 . The method of claim 1 , wherein the third composition comprises about 30 wt. % to about 40 wt. % of the acid.
14 . The method of claim 13 , wherein the third composition comprises about 10 wt. % to about 40 wt. % methanesulfonic acid.
15 . The method of claim 1 , wherein the well is a multilateral well comprising at least two lateral sections.
16 . The method of claim 15 , wherein the first composition is introduced to a lateral section of the well in which a filter cake is located.
17 . The method of claim 15 , wherein the first composition is introduced to more than one lateral section before the second composition is introduced to the well.
18 . The method of claim 15 , comprising plugging a lateral section of the well before introducing the first composition.
19 . The method of claim 1 , comprising introducing a diverter to the well before introducing the first composition.
20 . The method of claim 1 , wherein the second composition comprises brine, seawater, hydrochloric acid, formic acid, acetic acid, a carboxylic acid, an alkylsufonic acid, a metal chelating agent, a linear polymer, a crosslinked polymer, a gelling agent, an emulsifier, a foaming agent, a defoaming agent, or combinations thereof.
21 . The method of claim 20 , wherein the second composition comprises about 0.1 wt. % to about 32 wt. % hydrochloric acid.
22 . The method of claim 20 , wherein the second composition comprises about 0.1 wt. % to about 12 wt. % formic acid.
23 . The method of claim 20 , wherein the second composition comprises about 0.1 wt. % to about 20 wt. % acetic acid.
24 . The method of claim 20 , wherein the second composition comprises about 0.1 wt. % to about 20 wt. % methanesulfonic acid.
25 . The method of claim 20 , wherein the second composition comprises a metal chelating agent selected from the group consisting of EDTA, MGDA, GLDA, and HEDTA at a concentration of about 0.1 wt. % to about 40 wt. %.
26 . The method of claim 1 , wherein the first composition is a gel comprising one or more of a linear polymer, a cross-linked polymer, or a viscoelastic surfactant.
27 . The method of claim 1 , wherein the first composition is an emulsion comprising a diesel fuel or an oil.
28 . The method of claim 1 , wherein the first composition is a foam comprising a gas.
29 . The method of claim 28 , wherein the gas is selected from one or more of air, nitrogen, carbon dioxide, methane, ethane, propane, natural gas, oxygen, and hydrogen.
30 . The method of claim 1 , wherein the first composition is simultaneously introduced into the well with a gas.
31 . A method for treating a multi-lateral well in a geologic formation comprising:
a) introducing to a lateral section of the multi-lateral well a first composition comprising about 68 wt. % to about 72 wt. % of an alkylsulfonic acid; and
b) introducing to the lateral section of the multi-lateral well a second composition comprising water,
wherein the first and second compositions combine in the lateral section to form a third composition comprising about 30 wt. % to about 40 wt. % of the alkylsulfonic acid.
32 . The method of claim 31 , wherein the acid is methanesulfonic acid.
33 . The method of claim 32 , wherein the third composition comprises about 30 wt. % methanesulfonic acid.
34 . The method of claim 31 , wherein the first composition is introduced to more than one lateral section before the second composition is introduced to the multi-lateral well.
35 . The method of claim 31 , comprising plugging a lateral section of the well before introducing the first composition.
36 . The method of claim 31 , comprising introducing a diverter to the well before introducing the first composition.
37 . The method of claim 31 , wherein the second composition comprises brine, seawater, hydrochloric acid, formic acid, acetic acid, a carboxylic acid, an alkylsulfonic acid, a metal chelating agent, a linear polymer, a crosslinked polymer, a gelling agent, an emulsifier, a foaming agent, a defoaming agent, or combinations thereof.
38 . The method of claim 31 , wherein the first composition is a gel comprising one or more of a linear polymer, a cross-linked polymer, or a viscoelastic surfactant.
39 . The method of claim 31 , wherein the first composition is an emulsion comprising a diesel fuel or an oil.
40 . The method of claim 31 , wherein the first composition is a foam comprising a gas.