A method of reducing the viscosity of a crude oil, the method comprising adding to the crude oil (i) a surfactant compound including at least two hydrophobic groups wherein the resultant mixture has a water content of less than 10 vol %.

A method and hydraulic fracturing fluid that is a viscoelastic surfactant (VES) fracturing fluid having a surfactant and an inorganic oxidizer salt for hydraulic fracturing of a geological formation. The VES fracturing fluid is provided through a wellbore into the geological formation to hydraulically fracture the geological formation to form hydraulic fractures in the geological formation. The method includes oxidizing organic material in the hydraulic fractures with the VES fracturing fluid.

A method and hydraulic fracturing fluid that is a viscoelastic surfactant (VES) fracturing fluid having a surfactant and an inorganic oxidizer salt for hydraulic fracturing of a geological formation. The VES fracturing fluid is provided through a wellbore into the geological formation to hydraulically fracture the geological formation to form hydraulic fractures in the geological formation. The method includes oxidizing organic material in the hydraulic fractures with the VES fracturing fluid.

A method of removing calcium-containing water-based filter cake from a wellbore involving contacting the calcium-containing filter cake with a biodegradable acid solution of water, hydrochloric acid, formic acid, citric acid, and a surfactant. The method is performed at a pressure of 200 to 400 psi and a temperature of 50 to 125° C. The method removes calcium-containing filter cake made of water, calcium carbonate, a polymer or starch and a clay. The method meets industry standard steel corrosion rates of less than 0.049 lb/ft.sup.2 per day. Also disclosed is a biodegradable acid solution of water, hydrochloric acid, formic acid, citric acid, and a surfactant that meets OECD 301B thresholds for ready biodegradability.

A method of removing calcium-containing water-based filter cake from a wellbore involving contacting the calcium-containing filter cake with a biodegradable acid solution of water, hydrochloric acid, formic acid, citric acid, and a surfactant. The method is performed at a pressure of 200 to 400 psi and a temperature of 50 to 125° C. The method removes calcium-containing filter cake made of water, calcium carbonate, a polymer or starch and a clay. The method meets industry standard steel corrosion rates of less than 0.049 lb/ft.sup.2 per day. Also disclosed is a biodegradable acid solution of water, hydrochloric acid, formic acid, citric acid, and a surfactant that meets OECD 301B thresholds for ready biodegradability.

A brine-based viscosified pill including (1) a viscosified brine, (2) a surfactant-solvent blend containing about 5 wt. % to about 40 wt. % of at least one nonionic surfactant; about 5 wt. % to about 20 wt. % of at least one polyglycerol ester, about 20 wt. % to about 60 wt. % of at least one co-solvent; about 20 wt. % to about 25 wt. % water; and optionally about 1 wt. % to about 15 wt. % of at least one hydrophobic solvent, and (3) no solid weighting agent, may be introduced to a wellbore in an effective amount to clean the wellbore or displace fluid in the wellbore at a wide range of temperatures.

A brine-based viscosified pill including (1) a viscosified brine, (2) a surfactant-solvent blend containing about 5 wt. % to about 40 wt. % of at least one nonionic surfactant; about 5 wt. % to about 20 wt. % of at least one polyglycerol ester, about 20 wt. % to about 60 wt. % of at least one co-solvent; about 20 wt. % to about 25 wt. % water; and optionally about 1 wt. % to about 15 wt. % of at least one hydrophobic solvent, and (3) no solid weighting agent, may be introduced to a wellbore in an effective amount to clean the wellbore or displace fluid in the wellbore at a wide range of temperatures.

Disclosed are molybdenum-containing complexes used in compositions and methods for inhibiting or reducing the deposition of foulant on equipment.

Disclosed are molybdenum-containing complexes used in compositions and methods for inhibiting or reducing the deposition of foulant on equipment.

The subject invention provides multi-functional biochemical compositions, as well as their use in enhancing oil recovery from an oil-bearing subterranean formation. Advantageously, the compositions and methods of the subject invention are operationally-friendly, cost-effective, and environmentally-friendly. More specifically, in preferred embodiments, the subject invention provides a multi-functional composition for enhanced oil recovery (EOR) comprising one or more surfactants, one or more chelating agents, and one or more solvents.