Abstract
The effect of flow-through drying in sand production is analyzed. In flow-through drying, evaporation of the connate water of the reservoir sandstone occurs into the gas phase during natural gas production. This results from the compressibility of the gas. Near the wellbore the gas pressure drops and thus its relative humidity level drops as well. When an unsaturated gas flows through a medium, it can evaporate the connate water in the medium. Simultaneously, rock drying leads to capillary wicking form regions of higher water saturation. The strength of sandstone is affected by the water saturation with dry rock being stronger than water saturated rock. Drying the formation near the well due to gas flow will thus lead to an increase in the critical stresses for failure and sand production. Results from coupled finite element simulations are presented that demonstrate this effect on the hollow cylinder test configuration. Experimental results corroborate the observed drying and the well strengthening.