Method of transporting viscous hydrocarbons

An improvement in the method of transporting viscous hydrocarbons through pipes is disclosed. Briefly, the improvement comprises adding water, certain specific surfactants and a basic material to the hydrocarbon. The resulting emulsion has a much lower viscosity and is more easily transported.

Application Ser. No. 13,358, filed Feb. 21, 1979, and having the same 
assignee as the present application, discloses and claims an improvement 
in the method of transporting viscous hydrocarbons through pipes wherein 
the improvement comprises adding water containing an effective amount of a 
low molecular weight alkaryl sulfonate. 
BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention is in the general field of improved methods of pumping 
viscous hydrocarbons through a pipe, such as a well-bore or a pipeline. 
2. General Background 
The movement of heavy crudes through pipes is difficult because of their 
high viscosity and resulting low mobility. One method of improving the 
movement of these heavy crudes has included adding to the crude lighter 
hydrocarbons (e.g. kerosine distillate). This reduces the viscosity and 
thereby improves the mobility. This method has the disadvantage that is is 
expensive and the kerosine distillate is becoming difficult to obtain. 
Another method of improving the movement of these heavy crudes is by 
heating them. This requires the installation of expensive heating 
equipment and thus is an expensive process. 
The use of oil-in-water emulsions, which use surfactants to form the 
emulsion is known in the art. 
I have found that the use of a small amount of a basic compound (e.g. NaOH) 
in conjunction with certain specific surfactants provides an improvement. 
The use of the basic compound reduces the amount of surfactant required 
and thereby reduces the cost. Furthermore, the use of the basic compound 
enables the use of such a small amount of surfactant that refining 
problems are reduced or eliminated. 
BRIEF SUMMARY OF THE INVENTION 
Briefly stated, the present invention is directed to an improvement in the 
method of pumping a viscous hydrocarbon through a pipe wherein the 
improvement comprises forming an oil-in-water emulsion by adding to said 
hydrocarbon from about 20 to about 80 volume percent water, containing 
minor but effective amounts of the combination of (a) an alkali metal or 
ammonium hydroxide and (b) certain specific surfactants which are selected 
from the group consisting of water-soluble alkylbenzene sulfonates and an 
ethoxylated phenol nonionic. 
DETAILED DESCRIPTION 
Insofar as is known my method is suitable for use with any viscous crude 
oil. 
The amount of water which is used is suitably in the range of about 20 to 
about 80 volume percent based on the hydrocarbon. A preferred amount of 
water is in the range of about 40 to 60 volume percent. The water can be 
pure or can have a relatively high amount of dissolved solids. Any water 
normally found in the proximity of a producing oil-well is suitable. 
Suitable basic compounds for addition to the water include the hydroxides 
of sodium, potassium and ammonium. Sodium hydroxide is preferred by reason 
of cost and availability. The amount of basic compound present in the 
water suitably is in the range of about 400 to about 10,000 parts per 
million (ppm) by weight. Preferably, the amount of basic compound is in 
the range of about 600 to about 1250 parts per million by weight. 
Two types of surfactants are suitable for use in my invention. The first 
type is a sodium or potassium salt of an alkylbenzene sulfonate containing 
about 8 to about 14 carbon atoms in the alkyl group or groups. The benzene 
can be either monoalkyl- or dialkyl-substituted, but preferably is 
monoalkyl. The alkyl group or groups can be linear or branched chain. The 
preferred surfactant, in this type, is a sodium monoalkylbenzene sulfonate 
wherein the alkyl group contains about 11 to about 13 carbon atoms. 
The second type of surfactant comprises two specific nonionics. First, an 
ethoxylated mono- or dialkyl phenol, wherein each alkyl group contains 
from about 8 to about 12 carbon atoms, said ethoxylated alkyl phenol 
containing from about 20 to about 100 ethoxy groups, preferably from about 
30 to about 70 ethoxy groups. Second, in some cases the ethoxylated phenol 
can be in combination with a polyethylene glycol, said polyethylene glycol 
having a molecular weight in the range of about 1,000 to about 3,000, 
preferably about 1800 to about 2200. When the glycol is present typically 
the combination contains a phenol to glycol weight ratio of about 4:1. 
A suitable amount of surfactant is in the range of about 10 to about 500 
parts by million by weight, preferably about 50 to about 100 parts per 
million (ppm) by weight. 
In order to illustrate the nature of the present invention still more 
clearly the following examples will be given. It is to be understood, 
however, that the invention is not to be limited to the specific 
conditions or details set forth in these examples except insofar as such 
limitations are specified in the appended claims. 
The following materials were used in the tests described herein: 
Crude Oil--Goodwin lease crude from Cat Canyon oil field, Santa Maria, 
California 
Water--Goodwin synthetic (Water prepared in laboratory to simulate water 
produced at the well. It contained 4720 ppm total solids.) 
Sodium Hydroxide--C.P. grade, pellet form 
Surfactants 
A--sodium monoalkylbenzene sulfonate having a molecular weight of 
approximately 334 
B--A nonionic as described in the foregoing. 
The nonionic will be identified more specifically in the examples. 
Viscosities were determined using a Brookfield viscometer, Model LV with 
No. 3 spindle. The procedure is described below. 
Test Procedure 
Three hundred ml of crude oil, preheated in a large container to about 
93.degree. C. in a laboratory oven, was transferred to a Waring blender 
and stirred at medium speed until homogeneous. Stirring was stopped, 
temperature recorded, and the viscosity measured using the Brookfield 
viscometer at RPM's (revolutions per minute) of 6, 12, 30 and 60. 
Viscosity was calculated by using a multiplication factor of 200, 100, 40 
and 20 for the respective speeds times the dial reading on the viscometer.