Effect of acidizing rate on enhanced oil recovery for Eocene Thebes limestone, Eastern of the Gulf of Suez, Egypt

摘要

Thebes Limestone of Eocene age contributes to oil producing reservoir of Abu Rudeis Field. Acidizing process has been applied successfully for many years to increase the productivity of petroleum wells in carbonate formations, consequently demands of application acidizing techniques are increasing. Carbonate acidizing differs than that occurs in sandstone because the reactive nature of a carbonate rock, as a result of this, carbonate acidizing causes formation of large flow channels in some portions of the rock comparing with the original pore size distrubution, in addition enlarging of some aspects as diameters, areas and volumes of original pores. This study investigated that the presence of oil slows reaction rate of HCL acid with a carbonate reservoir rock, where the treatment of carbonate reservoir rock with high concentrated HCL acid speeds up the acidizing rate, decreases the effect of oil within the rock and creates much new channels that facilitate injectivity and productivity of oil wells. The effects of acidizing on carbonate rocks at various conditions were different and obvious, consequently help us to improve the oil recovery from reservoir rocks.