Experimental Study of External as well as Internal Core Formation Damage

Water injection is always considered the optimum technique for recovery of additional oil from mature fields, as it can be used to support the reservoir energy as a secondary recovery method. It can also be part of the waste water management industry, where the produced water is filtered and re-injected to the ground. Apart from the purpose of water injection, the phenomenon of low injection is always linked to water injection projects. One of the main reasons for this phenomenon is the solid particles that are suspended in water. These solid particles are filtered by the porous medium and are retained in the pores of the grains matrix. Water quality is considered one of the most important factors that affect the injectivity decline phenomenon. In the first part of this study, water quality has been characterized by studying the stability of the suspended solid particles in water in order to determine the optimum conditions of salinity, PH and suspended solid particles size and concentration at which the effect of flocculation and coagulation is very low. By the end of this study a certain range of brine salinity, PH and suspended solid particles size and concentration were selected to be used in the second part of this research. After that, Core flooding experiments were conducted on Bentheimer sandstone core plugs using brine solution representing the North Sea composition and Baracarp solid particles (CaCo3) at different flow rate. Pressure measurements were obtained along the core in order to analyse the retention of the suspension particles along the core plug. Moreover, the influent and effluent samples were taken during the core flood experiments to study the change in the suspension concentration and how the core plug is acting as a filter.