Arif
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02:07:09 pm on December 25, 2009 | # |
Processes such as steam flooding involve injecting high-pressure steam at about 340° C into the oil bearing rock formations. The steam heats the crude oil, reducing its viscosity and applying pressure to force the material through the rock matrix toward recovery wells. Unfortunately, the same changes in the physical characteristics of the crude oil that make it more mobile in the formation also render it more susceptible to capillary phenomena that can cause the oil mass to break up within the pores of the rocks and leave inaccessible pockets of oil droplets. In such processes, surfactants are used to alter the wetting characteristics of the oil–rock–steam interfaces to improve the chances of successful recovery. Those surfactants must be stable under the conditions of use such as high temperatures and pressures and extremes of pH.