Use of Wet Gas To Model Long-Term Fracture Conductivity

Significant advances have recently been made in laboratory attempts to measure realistic fracture conductivity values for proppants at reservoir conditions. This paper will give a brief overview of recent work throughout the industry related to conductivity testing, and efforts being made to simulate the environment of fracturing proppants during a well's producing life. Also presented will be data showing that test results can be significantly different when using wet gas as the flowing medium following a short period of flowing brine water. Listed below are the nine most important test parameters that need to be incorporated into the test procedure: -Reservoir Temperature -Extended test times -Core wafers -Gel residue within the proppant pack -Gel filter cakes from dynamic fluid loss tests -Shear preconditioning of fluids in fluid loss tests -Frac fluid clean-up -Wet nitrogen gas as flowing medium (to model gas wells) -Multiple closure stress values. Previous authors have modeled some of these variables, but this paper will present data where all parameters listed above are included. These test results will allow an operator to more accurately model a fracturing treatment with a design simulator and thus predict the post-frac production using a reservoir simulator.