Experimental study of hydraulic fracturing fluid effect on proppant permeability

Abstract

During hydraulic fracturing treatment, huge quantities of gel and Proppant are pumped into the formation. The fracture dimensionless conductivity (FCD) is a key parameter to optimize the hydraulic fracturing, to estimate the productivity index (PI) and the Folds of Increase (FOI). However, these parameters are affected by the closure pressure and gel residues which decrease the fracture conductivity. In this work some laboratory tests were proposed for gel viscosity measurement under bottom-hole conditions where the parameters temperature and fracturing fluid were investigated. A huge drop in the fracturing fluid viscosity was observed, varied between 74% to 77%, at a varied temperature of 85°C and 110oC. The results show that the gel was not broken, taking into consideration that the Hassi Messaoud reservoirs are under-pressurized which leads to a low retained fracture permeability that will affect the FCD and, as results, the PI due to the insufficient energy that needed for a better cleanup of the fracture.