Laboratory Investigation of Regained Rock Permeability Using High Viscosity Friction Reducer in Comparison to Linear Guar Fracture Fluids

Abstract

Hydraulic fracturing is a method employed for extracting oil and gas from unconventional reservoirs by pumping a mixture of water, sand, and additives into the reservoirs to fracture oil formations. A high viscosity friction reducer (HVFR) based on polyacrylamide is a popular chemical that has been employed recently during hydraulic fracturing treatments to help transport proppant and to reduce friction. However, the use of HVFRs at high concentrations, especially in regions with high concentration levels of total dissolved solids (TDS), has raised concerns over the possibility of formation damage. In this research, a new type of HVFR was investigated for its capacity to damage a formation utilizing various total dissolved solids (TDS) concentrations of Marcellus produced water (i.e., 22.9k [10%], 114.5k [50%] and 229k ppm [100%]) at a reservoir temperature of 65.5°C (150°F). The effect of the HVFR on the formation damage was assessed using various HVFR concentrations (i.e., 2, 4, and 8 gpt). For comparison, linear guar was utilized at different concentrations (i.e., 15, 25, and 35 ppt) under identical conditions. In addition, the study investigated the efficacy of several breaker types (i.e., ammonium persulfate [APS], sodium bromate [SB], and sodium persulfate [SPS]) in eliminating fracture fluid and reducing formation damage. This study aimed to optimize the design of hydraulic fracturing operations by evaluating the potential for formation damage caused by a high viscosity friction reducer (HVFR) and analyzing the ability of different breaker types to remove the HVFR after its use.