Abstract
In this paper, a numerical model for volumetric prediction of sand production in injector wells is presented. Sanding in injector wells is mainly associated with the back-flow and cross-flow generated during shut-in in addition to the waterhammer pressure pulsing in the wellbore due to fast flow rate changes. Emphasis is given to the geomechanical aspects of sanding such as rock fatigue due to cyclic pressure changes and the concomitant degradation of bonding between the sand grains. This model is robust in capturing the key parameters in the sandstone behavior such as stress-dependent elasticity, hardening, softening and dilatancy. Rock degradation is considered to be the necessary condition for sand production which is assumed to obey the erosion mechanics. The model is calibrated and validated using physical model tests carried out under various stresses and fluid flow conditions. The numerical model has been utilized to analyze sanding potential in a cased and perforated injector which will be presented to demonstrate the field application of the proposed concepts.
