A downhole tool includes a main body, and a setting member configured to press the main body radially outwards so as to set the main body with the surrounding tubular, made at least partially from a dissolvable material configured to dissolve in a well fluid, and defining a bore therein. The tool also includes an acid pill positioned in the bore of the setting member. The acid pill contains an acid therein, and is made at least partially from a dissolvable material configured to dissolve in the well fluid such that the acid mixes with the well fluid upon the acid pill at least partially dissolving. The acid mixed in the well fluid increases a rate at which the dissolvable material of the setting member dissolves in the well fluid.

A downhole tool includes a main body, and a setting member configured to press the main body radially outwards so as to set the main body with the surrounding tubular, made at least partially from a dissolvable material configured to dissolve in a well fluid, and defining a bore therein. The tool also includes an acid pill positioned in the bore of the setting member. The acid pill contains an acid therein, and is made at least partially from a dissolvable material configured to dissolve in the well fluid such that the acid mixes with the well fluid upon the acid pill at least partially dissolving. The acid mixed in the well fluid increases a rate at which the dissolvable material of the setting member dissolves in the well fluid.

A method for the fracking or stimulation of a hydrocarbon-bearing formation, said method comprising the steps of: providing a wellbore in need of stimulation; inserting a plug in the wellbore at a predetermined location; inserting a perforating tool and a spearhead or breakdown acid into the wellbore; positioning the tool at said predetermined location; perforating the wellbore with the tool thereby creating a perforated area; allowing the spearhead acid to come into contact with the perforated area for a predetermined period of time sufficient to prepare the formation for fracking or stimulation; removing the tool from the wellbore; and initiating the fracking of the perforated area using a fracking fluid. Also disclosed is a corrosion inhibiting composition for use with the acid composition.

A method for selective solution mining mineral recovery may include heating a wellfield injection brine to a temperature from about 100° C. to about 250° C.; injecting the heated wellfield injection brine into an underground wellfield to dissolve soluble minerals therein, creating a hot brine solution; removing the hot brine solution from the underground wellfield; and recovering the soluble minerals from the hot brine solution by cooling the hot brine solution to a temperature of from about −10° C. to about 5° C. and causing the soluble minerals to precipitate recovered minerals in a solid form.

Injection fluids formed of reverse emulsions and related methods of forming and using reverse emulsions for cavity control in solution mining. The reverse emulsion can reduce the volume of oil required to create an oil pad at the roof of a solution mining cavern in order to prevent vertical leaching and cavern collapse. The reverse emulsion can be formed from an emulsifier, a brine solution and oil. The emulsifier concentration can range from about 1% to about 5% by weight of the reverse emulsion. The emulsifier and the oil can be combined to form an oil/emulsifier mixture, wherein the oil/emulsifier mixture is combined with the brine solution to form the reverse emulsion. The oil/emulsifier mixture can be from about 1% to about 5% by weight of the reverse emulsion.

Injection fluids formed of reverse emulsions and related methods of forming and using reverse emulsions for cavity control in solution mining. The reverse emulsion can reduce the volume of oil required to create an oil pad at the roof of a solution mining cavern in order to prevent vertical leaching and cavern collapse. The reverse emulsion can be formed from an emulsifier, a brine solution and oil. The emulsifier concentration can range from about 1% to about 5% by weight of the reverse emulsion. The emulsifier and the oil can be combined to form an oil/emulsifier mixture, wherein the oil/emulsifier mixture is combined with the brine solution to form the reverse emulsion. The oil/emulsifier mixture can be from about 1% to about 5% by weight of the reverse emulsion.

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 system and method for harnessing geothermal energy using fracturing of hot rock. The system has at least a first well and a second well. The method involves introducing an alkali metal downhole in a first well. A solution is also introduced into the first well. The solution produces an exothermic reaction with the alkali metal. The gas and heat fracture the hot rock producing fractures. The fractures fluidly connects the first well to the second well. A solution, such as water, can be pumped through the first well, through the fractures, and into the second well. The hot rock passes geothermal energy to the water which can then be utilized.

Methods for the fracking or stimulation of a hydrocarbon-bearing formation are provided in multiple embodiments. According to one method, it comprises the steps of: providing a wellbore having a casing; inserting a plug in the wellbore at a predetermined location; inserting a perforating tool and an acidic composition into the wellbore; wherein the acidic composition includes a corrosion inhibiting composition comprising at least two compounds selected from: Group A-I, and wherein at least two compounds are selected from different groups of the Groups A-I.

The disclosure provides methods and systems for recovering a target mineral from a mineral-bearing deposit. One or more first wells and one or more second wells are drilled into the deposit, each well having a substantially vertical section and a substantially horizontal section, the horizontal section of the second wells located above the horizontal section of the first wells. At least one channel from the horizontal section of each first well toward the horizontal section of the second wells is established. A fluid is injected into the deposit from the horizontal section of the first wells to form one or more slots. A brine is recovered from the horizontal section of the second wells, forming a cavity. A salt solution is then injected into the cavity from the horizontal section of the second wells and a target mineral-enriched solvent is recovered from the first wells.