Method and solvent composition for stimulating the production of oil from a producing well

Claim 1

The method for removing viscous crude oil, waxes, asphaltenes and resin precipitates of petroleum origin from pore spaces of oil-bearing formations, wells and flow lines comprising contacting said waxes, asphaltenes and resin precipitates of petroleum origin with a solvent composition consisting essentially of between about 45 to 85 volume percent of a normally liquid aliphatic hydrocarbon boiling in the range of about 120° to about 550° F. selected from the group consisting of kerosene and aviation turbine fuels; about 5 to 45 volume percent of a normally liquid aromatic hydrocarbon having a boiling point above about 175° F. selected from the group consisting of benzene, toluene, ethylbenzene, cumene, mesitylene and propylbenzene; about 0.5 to 6 volume percent of an aliphatic ether of an aliphatic polyhydric alcohol containing at least one free hydroxyl group, having a boiling point above 212° F. and containing less than about 20 carbon atoms selected from the group consisting of ethylene glycol monobutyl ether and monomethyl ether diethylene glycol; and about 1 to 15 volume percent of a lower alkyl monohydric alcohol selected from the group consisting of methanol, ethanol, propanol, isopropanol and butanol.

Claim 2

The method for removing viscous crude oil, waxes, asphaltenes and resin precipitates of petroleum origin from pore spaces of oil-bearing formations, wells and flow lines comprising contacting said waxes, asphaltenes and resin precipitates of petroleum origin with a solvent composition consisting essentially of between about 45 to 85 volume percent of a normally liquid aliphatic hydrocarbon boiling in the range of about 120° to about 550° F. selected from the group consisting of kerosene and aviation turbine fuels; about 5 to 45 volume percent of a normally liquid aromatic hydrocarbon having a boiling point above about 175° F. selected from the group consisting of benzene, toluene, ethylbenzene, cumene, mesitylene and propylbenzene; about 0.5 to 6 volume percent of an aliphatic ether of an aliphatic polyhydric alcohol containing at least one free hydroxyl group, having a boiling point above 212° F. and containing less than about 20 carbon atoms selected from the group consisting of ethylene glycol monobutyl ether and monomethyl ether diethylene glycol; and about 1 to 15 volume percent of a lower alkyl monohydric alcohol selected from the group consisting of methanol, ethanol, propanol, isopropanol and butanol.

Claim 4

The method of treating an oil-bearing formation which comprises introducing into a well penetrating said formation a solvent consisting essentially of about 45 to 85 volume percent of a normally liquid aliphatic hydrocarbon boiling in the range of about 120° to about 550° F. selected from the group consisting of kerosene and aviation turbine fuels, about 5 to 45 volume percent of a normally liquid aromatic hydrocarbon having a boiling point above about 175° F. selected from the group consisting of benzene, toluene, ethylbenzene, cumene, mesitylene and propylbenzene, about 0.5 to 6 volume percent of an aliphatic ether of an aliphatic polyhydric alcohol containing at least one free hydroxyl group, having a boiling point above 212° F. and containing less than about 20 carbon atoms selected from the group consisting of ethylene glycol monobutyl ether and monomethyl ether diethylene glycol, and about 1 to 15 volume percent of a lower alkyl monohydric alcohol selected from the group consisting of methanol, ethanol, propanol, isopropanol and butanol; and thereafter applying fluid pressure to said solvent to force it into the interstices of said formation.

Claim 5

The method of treating an oil-bearing formation which comprises introducing into a well penetrating said formation a solvent consisting essentially of about 45 to 85 volume percent of a normally liquid aliphatic hydrocarbon boiling in the range of about 120° to about 550° F. selected from the group consisting of kerosene and aviation turbine fuels, about 5 to 45 volume percent of a normally liquid aromatic hydrocarbon having a boiling point above about 175° F. selected from the group consisting of benzene, toluene, ethylbenzene, cumene, mesitylene and propylbenzene, about 0.5 to 6 volume percent of an aliphatic ether of an aliphatic polyhydric alcohol containing at least one free hydroxyl group, having a boiling point above 212° F. and containing less than about 20 carbon atoms selected from the group consisting of ethylene glycol monobutyl ether and monomethyl ether diethylene glycol, and about 1 to 15 volume percent of a lower alkyl monohydric alcohol selected from the group consisting of methanol, ethanol, propanol, isopropanol and butanol; and thereafter applying fluid pressure to said solvent to force it into the interstices of said formation.

Claim 6

The method for removing waxes, asphaltenes and resin precipitates of petroleum origin from pore spaces of oil-bearing formations, wells and flow lines comprising placing in contact with said waxes, asphaltenes and resin precipitates of petroleum origin a solvent composition comprising about 50 to 80 volume percent of Jet A aviation turbine fuel, about 10 to 30 volume percent of toluene, about 1 to 5 volume percent of ethylene glycol monobutyl ether, and about 1 to 10 volume percent of isopropanol.

Claim 7

The method for removing waxes, asphaltenes and resin precipitates of petroleum origin from pore spaces of oil-bearing formations, wells and flow lines comprising placing in contact with said waxes, asphaltenes and resin precipitates of petroleum origin a solvent composition comprising about 50 to 80 volume percent of Jet A aviation turbine fuel, about 10 to 30 volume percent of toluene, about 1 to 5 volume percent of ethylene glycol monobutyl ether, and about 1 to 10 volume percent of isopropanol.