An acid mixture includes hydrochloric acid, a monoamine corrosion inhibitor, and at least one of a diamine corrosion inhibitor and an acid additive. A method for inhibiting corrosion in an acid treatment operation includes introducing an acid mixture comprising hydrochloric acid and a monoamine corrosion inhibitor into at least one of a subterranean formation and subterranean wellbore. The method also includes maintaining the amount of the monoamine corrosion inhibitor in the acid mixture in the subterranean formation and/or the subterranean wellbore in a range of 10 ppm to 400 ppm for the duration of the acid treatment operation. The corrosion rate of steel parts of an acidic fluid circulation system in the acid mixture may be within an acceptable corrosion rate in a temperature range of 20° C. to 135° C.

An acid mixture includes hydrochloric acid, a monoamine corrosion inhibitor, and at least one of a diamine corrosion inhibitor and an acid additive. A method for inhibiting corrosion in an acid treatment operation includes introducing an acid mixture comprising hydrochloric acid and a monoamine corrosion inhibitor into at least one of a subterranean formation and subterranean wellbore. The method also includes maintaining the amount of the monoamine corrosion inhibitor in the acid mixture in the subterranean formation and/or the subterranean wellbore in a range of 10 ppm to 400 ppm for the duration of the acid treatment operation. The corrosion rate of steel parts of an acidic fluid circulation system in the acid mixture may be within an acceptable corrosion rate in a temperature range of 20° C. to 135° C.

Multiple charged cationic compounds, which are derived from polyamines through an aza-Michael addition with an α, β-unsaturated carbonyl compound, in a clay treatment composition to reduces clay swelling, clay migration, and sludge formation in a subterranean formation in oil and gas operations are provided. The disclosed methods or compositions are found to be more effective than those methods or compositions commonly used for reducing clay swelling, clay migration, and sludge formation.

Multiple charged cationic compounds, which are derived from polyamines through an aza-Michael addition with an α, β-unsaturated carbonyl compound, in a clay treatment composition to reduces clay swelling, clay migration, and sludge formation in a subterranean formation in oil and gas operations are provided. The disclosed methods or compositions are found to be more effective than those methods or compositions commonly used for reducing clay swelling, clay migration, and sludge formation.

Solvent mixtures for downhole elemental sulfur removal and formation stimulation, and methods for utilizing such solvent mixtures, are described herein. One method includes providing a solvent mixture that includes an elemental sulfur solvent fraction and an odorant fraction that includes a lactate ester solvent. The method also includes injecting the solvent mixture into a hydrocarbon well such that the elemental sulfur solvent fraction of the solvent mixture dissolves elemental sulfur deposited on well components, and contacting the solvent mixture with water such that the lactate ester solvent within the odorant fraction reacts with the water to generate lactic acid. The method further includes stimulating a formation through which the hydrocarbon well extends by flowing the solvent mixture including the lactic acid through the hydrocarbon well and into the formation.

Solvent mixtures for downhole elemental sulfur removal and formation stimulation, and methods for utilizing such solvent mixtures, are described herein. One method includes providing a solvent mixture that includes an elemental sulfur solvent fraction and an odorant fraction that includes a lactate ester solvent. The method also includes injecting the solvent mixture into a hydrocarbon well such that the elemental sulfur solvent fraction of the solvent mixture dissolves elemental sulfur deposited on well components, and contacting the solvent mixture with water such that the lactate ester solvent within the odorant fraction reacts with the water to generate lactic acid. The method further includes stimulating a formation through which the hydrocarbon well extends by flowing the solvent mixture including the lactic acid through the hydrocarbon well and into the formation.

A method of repairing a well is provided. The method includes injecting a brine solution into the well, injecting carbon dioxide into the well, and reacting the brine solution in the reservoir rock with the carbon dioxide to form calcite such that calcite precipitates into the desired flow path between a cold well and a hot well to effectively repair short circuits within the EGS reservoir.

A method of repairing a well is provided. The method includes injecting a brine solution into the well, injecting carbon dioxide into the well, and reacting the brine solution in the reservoir rock with the carbon dioxide to form calcite such that calcite precipitates into the desired flow path between a cold well and a hot well to effectively repair short circuits within the EGS reservoir.

The disclosure is directed to a process for treating a subterranean earth formation by introducing a buffered acidizing treatment fluid comprising a monovalent salt of monochloroacetic acid and at least one acid into said subterranean earth formation, wherein the pH of the buffered acidizing treatment fluid is from about 1.2 to about 5. It also pertains to a buffered acidizing treatment fluid comprising a monovalent salt of monochloroacetic acid, at least one acid and optionally an element to suppress salt precipitation.

The disclosure is directed to a process for treating a subterranean earth formation by introducing a buffered acidizing treatment fluid comprising a monovalent salt of monochloroacetic acid and at least one acid into said subterranean earth formation, wherein the pH of the buffered acidizing treatment fluid is from about 1.2 to about 5. It also pertains to a buffered acidizing treatment fluid comprising a monovalent salt of monochloroacetic acid, at least one acid and optionally an element to suppress salt precipitation.