An Experimental Study on Permeability Reduction Resulting from Mixed BaSO4, CaSO4, and SrSO4 Scale Deposition in Porous Media during Water Injection

Sulfate scale deposition (BaSO4, CaSO4, and SrSO4) is a common problem in oilfield operationsaround the world, which causes significant formation damage during production and injectionactivities. This paper presents the results of an experimental study on the permeability reduction ofporous media due to sulfate scale deposition. A set of experiments were conducted to investigate theeffects of cation (Ba2+, Ca2+, and Sr2+ ions) concentration and the number of cation species on thepermeability reduction resulting from single sulfate scales (single BaSO4, CaSO4, and SrSO4 scales)and mixed BaSO4, CaSO4, and SrSO4 scale deposition in porous media during water injection. Theexperiments were performed at a constant temperature of 70 °C and a constant anion (SO42- ion)concentration of 3968 ppm in the pack of glass beads as the porous media. The results show that theintensity of permeability reduction increases with increasing cation concentration. These results alsodeclare that the permeability reduction of porous media due to mixed BaSO4, CaSO4, and SrSO4 isclearly severer than single scales.

Keywords:

Mixed Scale Formation , Single Scale , Permeability Reduction , Porous Media , Sulfate Scale