Oil recovery method using an aqueous fluid drive

Claim 2

The process of claim 1 wherein the solids are carbon black particles and wherein said aqueous solution also contains a dispersing surfactant.

Claim 3

A process according to claim 1 wherein therein is injected in said stratum through a well therein from 0.05 to 1 pore volume of an aqueous slug comprising: a. a suspension of minute solids of a size in the range of 0.001 to 1 micron capable of being driven through said stratum by aqueous fluid drive to assist in displacing oil therefrom; b. an oil-displacing surfactant having the formula R-R''-R''''-H wherein R is an aliphatic alkyl of nine to 20 carbon atoms or an alkylaryl of which the alkyl has eight to 20 carbon atoms and the aryl is attached to R'', R'' is O or S, and R'''' is polyethylene oxide of an average of four to 11 units, in solution in a concentration in the range of 0.001 to 2 weight percent; and c. a dispersing surfactant having the formula R-O-R''-H wherein R is an aliphatic alkyl of five to 20 carbon atoms or an alkylaryl, the alkyl having eight to 20 carbon atoms and the aryl is attached to the O, and R''is a polyethylene oxide of an average of 30 to 100 units, in solution in a concentration in the range of 0.001 to 2 weight percent.

Claim 4

The process of claim 4 wherein said solids of (a) are carbon black particles.

Claim 5

The process of claim 4 wherein the surfactant of (b) is nonylphenoxypolyethanol having an average chain length on the hydrophilic end in the range of 6 to 6.5 moles or units of ethylene oxide and is present in a concentration of 0.1 to 1 weight percent.

Claim 6

The process of claim 4 wherein the surfactant of (c) is a nonylphenoxypolyethanol having an average chain length on the hydrophilic end in the range of 95 to 100 moles or units of ethylene oxide and is present in a concentration of 0.1 to 1 weight percent.

Claim 7

The process of claim 4 wherein the solids of (a) are carbon black, the surfactant of (b) is nonylphenoxypolyethanol having an average chain length on the hydrophilic end in the range of 6 to 6.5 moles or units of ethylene oxide and is present in a concentration of 0.1 to 1 weight percent, and the surfactant of (c) is a nonylphenoxypolyethanol having an average chain length on the hydrophilic end in the range of 95 to 100 moles or units of ethylene oxide and is present in a concentration of 0.1 to 1 weight percent.

Claim 8

A waterflooding medium comprising an aqueous liquid; and a mixture of additives including: a. a suspension of minute solids of a size in the range of 0.001 to 1 micron; b. an oil-displacing surfactant having the formula R-R''-R''''-H wherein R is an aliphatic alkyl of nine to 20 carbon atoms or an alkylaryl of which the alkyl has eight to 20 carbon atoms and the aryl is attached to R'', R'' is O or S, and R'''' is polyethylene oxide of an average of four to 11 units, in solution in a concentration in the range of 0.001 to 2 weight percent; c. a dispersing surfactant having the formula R-O-R''-H wherein R is an aliphatic alkyl of five to 20 carbon atoms or an alkylaryl, the alkyl having eight to 20 carbon atoms and the aryl is attached to the O, and R'' is the polyethylene oxide of an average of 30 to 100 units, in solution in a concentration in the range of 0.001 to 2 weight percent; and d. a polysaccharide viscosifying agent in solution in a concentration in the range of 0.1 to about 0.5 weight percent.

Claim 9

The composition of claim 9 wherein (a) is carbon black, (b) is nonylphenoxypolyethanol having an average chain length on the hydrophilic end in the range of 6 to 6.5 moles or units of ethylene oxide, and (c) is a nonylphenoxypolyethanol having an average chain length on the hydrophilic end in the range of 95 to 100 moles or unitS of ethylene oxide, and wherein the concentration of (b) and (c) is in the range 0.1 to 1 weight percent.