Method of transporting viscous hydrocarbons

Claim 1

In the method of transporting a viscous hydrocarbon through a pipe the improvement which comprises forming an oil-in-water emulsion by adding to said hydrocarbon from about 20 to about 80 volume percent of an aqueous solution containing an effective amount of a combination of (a) about 25 to about 20,000 parts per million, based on said hydrocarbon, of a salt of an ethoxylated alcohol sulfate which is represented by the formula [CH.sub.3 (CH.sub.2).sub.x CH.sub.2 (OCH.sub.2 CH.sub.2).sub.n OSO.sub.3 ]M wherein x is an integer in the range of about 10 to about 16, n is a number in the range of about 3 to 12, and M is sodium or ammonium, and (b) about 50 to about 20,000 parts per million of a second surfactant selected from the group consisting of (i) materials represented by the formula ##STR8## a and c are numbers in the range of 2 to 10, with the sum of a and c being in the range of 4 to 20, and b is a number in the range of 6 to 30, (ii) materials represented by the formula ##STR9## a and c are numbers in the range of 3 to 15, with the sum of a and c being in the range of 6 to 30, and b is a number in the range of 4 to 20, and (iii) materials represented by the formula ##STR10## R is a linear alkyl group containing 10 to 18 carbon atoms, a is a number in the range of 6 to 30 and b is a number in the range of 4 to 20.