High efficiency reservoir stimulation based on temporary plugging and diverting for deep reservoirs

Abstract

To tackle the challenge of great depth, high pressure and high temperature (HPHT), low permeability and porosity, serious heterogeneity in deep oil/gas reservoirs, this paper proposed high efficiency reservoir stimulation based on temporary plugging & diverting, which can realize multi-stage stimulation to improve stimulated rock volume (SRV) without mechanical isolating tools. A series of degradable nanometer ester temporary plugging material with high temperature resistance and high strength has been developed. The feasibility of the method was tested by modeling experiment, and the performance of the plugging material was evaluated. The high efficiency stimulating technology based on chemical plugging & diverting can avoid the problems of high cost and high risk operations by mechanical isolating tools in HPHT deep wells. This technology has been applied in 211 wells from 10 deep oil/gas reservoirs in China, with average production increment per well 3.5 times higher than conventional technologies. This technology enhanced reservoirs production and stimulation effect, lowered the operation difficulty and risk, and decreased multi-stage stimulation cost for deep reservoirs. Key words: deep reservoir, reservoir stimulation, temporary plugging and diverting, high temperature resistance, high strength, degradable chemical plugging material