Mechanisms of scale deposition and scale removal in porous media

Calcium sulfate scaling and scale removal have been studied experimentally and theoretically in a well-defined unconsolidated porous medium. The effects of injection rate, scale concentration and temperature on the rate of scale formation and the rate of its removal are investigated. The results of the experiments are used to develop mechanistic models for the prediction of the scaling process in porous media and for removal of the deposits by dilute sulfuric acid solutions. The predictions of the suggested models for scaling and cleaning are compared with measured data. Deviations ranging from 11% to 14% are observed, which confirm the suitability of the models.