Abstract
Experiments have been performed to determine the rate of water vaporization in core samples at initial water saturation. The effect of pressure on rate of water vaporization has been studied. The experiments indicate that as pressure decreases from 2000 to 1000 psi, at constant temperature of 90°C, the rate of water vaporization increases from approximately 0.016 to 0.025 g/min. The effect of increase in temperature from 90°C to 100°C, at constant pressure of 1500 psi, is to increase the rate of water vaporization from 0.018 to 0.029 g/min. All the experiments were performed with the core samples at initial water saturation of 18%. As vaporization takes place, the brine remaining in the core sample becomes more concentrated. If concentration exceeds the critical supersaturation value, minerals will precipitate out into the formation. Additionally, the effect of salt precipitation on absolute permeability was determined. The results indicate that reduction in absolute permeability after the vaporization experiments ranges from approximately 14 to 30%.
