Design and Investigation of Fracturing Fluid for High Temperature High Pressure Reservoir

Abstract

Hydraulic fracturing is the most commonly applied stimulation technique used in low permeability reservoir but also extended to high permeability reservoir to enhance the production. Fracturing fluid is a critical component of the hydraulic fracturing treatment. It main functions are to open the fracture and to transport propping agent along the length of the fracture. The viscous properties of the fluid are usually considered the most important for carrying the proppant inside the fracture. The fracturing fluid loses its viscosity at higher temperature & therefore its ability to transport the proppant inside the fracture. The indigenously available fracturing fluids are stable up to 120˚ C only. While many of the Indian reservoirs bear temperature exceeding 120˚ C, which earnestly need hydro-fracturing for its economic exploitation. Although multinational service providers have developed few formulations, but provide them with services at an exorbitant cost. It therefore warrant immediate R&D work to help the Indian industries. The present work is to investigate the factors responsible for Frac-fluid degradation at higher temperature and to provide Indian industries a fluid system, which can open the formation effectively at the high temperatures, the system which uses low polymer-gel loading and an optimized crosslinker system. The Frac-fluid system so developed in the laboratory of well stimulation service (WSS) Ahmedabad in association with a group of scientists from WSS has been found to exhibit very predictable viscosity and efficiency and tends not to thermally thin upto 140˚ C as other fracture fluids. The low gel concentration will help to yield greater regained permeability of the proppant pack. While, experimental procedures perused and parameters achieved have been brought out in the report. The details of chemicals and their concentration have been consciously concealed to facilitate proper documentation for patent of this product. Further R&D efforts will be needed to establish stability up to 200˚ C.