A Model System to Study the Precipitation and Migration of Colloidal Particles in Porous Media (original) (raw)
1996, Journal of Colloid and Interface Science
these fines lead to severe changes in the permeability of Studies on the formation and migration of colloidal iron sulfide the porous rock that result in a decline of the overall oil in porous media were carried out using consolidated artificial aluproduction. In the petroleum industry this phenomena is mina-kaolin cores sintered at 1500ЊC. The artificial aluminacalled ''formation damage'' (2). kaolin cores were imbibed with a solution containing thioacetam-Despite its importance, there are few studies on the formaide and ferrous ions and heated at 80ЊC to obtain the formation tion and migration of colloidal particles in porous media. of FeS particles. Scanning electron micrographs showed particles Matijevic and co-workers have studied the adhesion of partiless than 1 mm in diameter and aggregates of different sizes covcles to macroscopic flat surfaces and the mechanisms inering the surface of the porous media. Core flooding experiments volved in their removal or mobilization (3, 4). Their results, showed that the migration of the fine FeS particles reduced the permeability of core and the injection of surfactant solutions at however, do not apply to porous rocks. The migration of constant salinity restored the original permeability after the profines in porous media has received attention due, mainly, to duction of the redispersed iron sulfide particles, in some cases. its importance in oil production (5). In most of the studies, ᭧ 1996 Academic Press, Inc. porous rocks, like Berea sandstone (6, 7), already containing particles have been used and the results are usually interpreted in terms of colloidal forces, assuming a particular composition for both the porous media and the particles. Another 1
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