Application of a new plant Surfactant in Rock Wettability Alteration

Wettability is one of most important factors affecting oil recovery in oil reservoirs. This factor comes in more consideration in carbonate reservoirs because they are mostly mixed to oil wet and therefore do not allow the large part of underground oil to be mobilized and recovered. Moreover oil wet rocks have weak potential to imbibe water, releasing the oil to be produced so we encounter low oil recovery in water flooding mechanism. Dissolving low concentration of surface active materials which called surfactants in injected water can noticeably improve water flooding oil recovery. This occurs because surfactants can alter wettability of oil wet rocks to more water wet state. But environmental issues and high cost of industrial surfactants have encountered petroleum industry with undesired problems. Therefore, in new oil view, plant surfactants are favorable because of having no environmental problems, availability and low cost of them. In this paper a new plan surfactant (derived from Morus nigra leaves) was introduced and effect of it on wettability alteration (by contact angle method) investigated. The results showed the plant surfactant altered the wettability of carbonate rock pieces from 100 to 20 degrees for water wet state and 150 to 30 degrees for oil wet state.

Keywords:

plant surfactant , Morus nigra , EOR , wettability alteration , GC-MS