Silica Transport During Steam Injection into Oil Sands: Dissolution and Precipitation Kinetics of Quartz - New Results and Review of Existing Data

The literature on quartz and silicate dissolution kinetics is briefly reviewed. Fifteen dissolution and seven precipitation experiments, with time as the independent variable, and four dissolution experiments, with the ratio A/M (surface area of sand)/mass of water) as the independent variable, are described. The experiments were carried out at temperatures between 121 and 255 degrees Celsius. Oil sand from which the bitumen had been previously extracted was used in all dissolution experiments. Both parabolic and first-order-rate laws could be fitted to the data. The use of either rate law leads to an activation energy for precipitation in the range 51-55 kJ mole^-1. Depending on the way an experiment is conducted, the ratio A/M may affect the results. The first-order-rate law is useful for predicting silica mass transport during steam injection.