An Experimental Study of the Effects of Salt Solutions on Formation Damage in a Water Injection Operation in Petroleum Reservoirs

Abstract

Many laboratory studies show that numerous variables related to crude oil, reservoir rock, and salt water exists that affect production rates. Meanwhile, many observations have shown that the combination of salt-water properties and injection conditions has a prominent effect on the microscopic displacement of crude oil by injecting water. A crucial reduction of injectivity of wells may occur due to formation damage during the process of water injection in petroleum reservoirs. Therefore, study of the effect of different salts in the injected water on the level of permeability reduction of reservoir rock and formation damage and the corresponding reduction of oil production is critical. The authors investigated the effect of salts including NaCl, KCl, CaCl2, and MgCl2 on reduction of the permeability of formations in different temperatures, flow rates, and concentrations. Also, a comparison of the type of salt in the same conditions was performed. Moreover, different solutions were made by a combination of salts including NaCl, CaCl2, and KCl and the solutions were compared based on the permeability reduction at the same concentration, temperature, and flow rates. At the end, of interesting suggestions were proposed regarding the composition and conditions of injected water to minimize formation damage and increases crude oil production.