Optimizing Fracturing-Fluid Cleanup in the Bossier Sand

This article, written by Assistant Technology Editor Karen Bybee, contains highlights of paper SPE 90030, "Optimizing Fracturing-Fluid Cleanup in the Bossier Sand Using Chemical Frac Tracers and Aggressive Gel-Breaker Deployment," by R. Sullivan, SPE, Anadarko Petroleum Corp.; R. Woodruff, SPE, ProTechnics Div. of Core Laboratories; A. Steinberger-Glaser, SPE, and R. Fielder, SPE, Anadarko Petroleum Corp.; and M. Asadi, SPE, ProTechnics Div. of Core Laboratories, prepared for the 2004 SPE Annual Technical Conference and Exhibition, Houston, 26-29 September. Proper fluid and proppant placement are critical to a successful propped-fracture stimulation treatment. Even with effective treatment placement, well performance often is affected detrimentally by incomplete gel breaking and fluid recovery. A technique that uses a family of environmentally friendly, fracturing-fluid-compatible chemical tracers has been used to quantify segment-by-segment fracturing-fluid recovery. With this technology, individual-fluid-segment cleanup and recovery can be enhanced by optimizing fracturing-fluid selection. Chemical Fracture Tracers (CFTs) Chemical fracture tracing was developed to increase the understanding of the dynamics of hydraulic-fracture placement and fluid flowback/cleanup. Borrowing from many years of experience with interwell tracing, several families of nonradioactive chemical compounds were identified that could be placed in segmented portions of the fracture fluid to measure the flowback efficiency of each fluid segment. CFTs are designed to be placed in chemically differentiated and/or proppant-differentiated fluid segments of the fracturing fluid to assess the cleanup of the fracture as a function of segment fluid chemistry and/or fracture geometry.