The invention relates to an inverse polymer emulsion having the particular feature of auto-inverting without any need for the use of an inverting agent and containing a polymer of at least one water-soluble monomer and at least one LCST macromonomer. The invention also relates to the use of the inverse emulsion in the fields of the oil and gas industry, water treatment, slurry treatment, paper manufacturing, construction, mining, cosmetics, textiles, detergents or agriculture.

The invention relates to an inverse polymer emulsion having the particular feature of auto-inverting without any need for the use of an inverting agent and containing a polymer of at least one water-soluble monomer and at least one LCST macromonomer. The invention also relates to the use of the inverse emulsion in the fields of the oil and gas industry, water treatment, slurry treatment, paper manufacturing, construction, mining, cosmetics, textiles, detergents or agriculture.

The present application concerns a water-in-oil inverse emulsion comprising: oil; water; at least one water-soluble anionic polymer of average molecular weight higher than 3 million daltons, containing between 4 and 14 mol % of sulfonated anionic monomers, between 0 and 17 mol % of carboxylated anionic monomers and between 69 and 94 mol of nonionic monomers; at least one inverting agent and at least one emulsifying agent, the weight ratio R between the total amount of inverting agent and the total amount of emulsifying agent being higher than 1.8; the inverting agent being selected from among an ethoxylated nonylphenol preferably having between 4 and 10 ethoxylations; an ethoxylated/propoxylated alcohol preferably having ethoxylations/propoxylations to obtain a total number of carbons of between C12 and C25, an ethoxylated tridecylic alcohol and an ethoxylated/propoxylated fatty alcohol; the emulsifying agent being selected from among sorbitan monooleate, polyethoxylated sorbitan esters or the diethanolamide of tall oil fatty acids, polyethoxylated fatty acids, and use thereof for hydraulic fracturing.

The present application concerns a water-in-oil inverse emulsion comprising: oil; water; at least one water-soluble anionic polymer of average molecular weight higher than 3 million daltons, containing between 4 and 14 mol % of sulfonated anionic monomers, between 0 and 17 mol % of carboxylated anionic monomers and between 69 and 94 mol of nonionic monomers; at least one inverting agent and at least one emulsifying agent, the weight ratio R between the total amount of inverting agent and the total amount of emulsifying agent being higher than 1.8; the inverting agent being selected from among an ethoxylated nonylphenol preferably having between 4 and 10 ethoxylations; an ethoxylated/propoxylated alcohol preferably having ethoxylations/propoxylations to obtain a total number of carbons of between C12 and C25, an ethoxylated tridecylic alcohol and an ethoxylated/propoxylated fatty alcohol; the emulsifying agent being selected from among sorbitan monooleate, polyethoxylated sorbitan esters or the diethanolamide of tall oil fatty acids, polyethoxylated fatty acids, and use thereof for hydraulic fracturing.

A method for recovering subsurface fluid from rock formations by adding an enzyme-based green solvent to a carrier fluid and injecting the enzyme-based green solvent and the carrier fluid into a production well. The enzyme-based green solvent and the carrier fluid are directed down a flow path of the production well. The solvent soaks in the production well before reversing the flow path of the production well. The enzyme-based green solvent and the carrier fluid travel up the flow path with a plurality of recovered deposits from the production well in the enzyme-based green solvent.

A method for reducing lost circulation in a subterranean formation. The method includes providing a treatment fluid comprising a base fluid and a lost circulation material comprising cane ash. The treatment fluid is introduced into a wellbore within the subterranean formation such that at least a portion of the cane ash bridges openings in the subterranean formation to reduce loss of fluid circulation into the subterranean formation.

A method for reducing lost circulation in a subterranean formation. The method includes providing a treatment fluid comprising a base fluid and a lost circulation material comprising cane ash. The treatment fluid is introduced into a wellbore within the subterranean formation such that at least a portion of the cane ash bridges openings in the subterranean formation to reduce loss of fluid circulation into the subterranean formation.

A method for reducing lost circulation in a subterranean formation. The method includes providing a treatment fluid comprising a base fluid and a lost circulation material comprising brown mud. The treatment fluid is introduced into a wellbore within the subterranean formation such that at least a portion of the brown mud bridges openings in the subterranean formation to reduce loss of fluid circulation into the subterranean formation.

A method for reducing lost circulation in a subterranean formation. The method includes providing a treatment fluid comprising a base fluid and a lost circulation material comprising brown mud. The treatment fluid is introduced into a wellbore within the subterranean formation such that at least a portion of the brown mud bridges openings in the subterranean formation to reduce loss of fluid circulation into the subterranean formation.

Certain invert emulsion treatment fluids for use in subterranean formations are provided. In certain embodiments, the methods comprise: providing an invert emulsion treatment fluid that comprises an oleaginous external phase, and an internal phase that comprises one or more alcohols and one or more polar organic compounds that are soluble in the internal phase; and introducing the treatment fluid into at least a portion of a subterranean formation.