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arXiv · 2309.03997

Energy-Efficient Fracturing Based on Stress-Coupled Perforation

Abstract

Hydraulic fracturing is one of the key technologies for reservoir stimulation in low-permeability/unconventional oil and gas fields. In response to the high energy consumption and greenhouse gas emissions caused by extreme flow-limiting perforation in hydraulic fracturing, stress-coupled perforation technology has been proposed to promote low-energy consumption and high efficiency in artificial fracturing. Based on the stress distribution in perforation hole and fracture propagation mechanism, a mathematical model for fracture propagation was established based on linear elastic fracture mechanics theory. Taking into account rock mechanical parameters, tensile effects at the crack tip, stress on both sides of the main crack and fracturing parameters, the real-time stress distribution and fracturing energy consumption were calculated using Monte Carlo random method and Newton's iterative method. With the unit fracture area energy consumption, total fracture area, and fracture uniformity as objective functions, the number and diameter of perforation holes were fully coupled and optimized. The developed simulator balances the calculation efficiency and accuracy of multiple fracture propagation. The study shows that under the condition of the same reservoir fracture volume, stress-coupled perforation technology will reduce energy consumption by 37%. This technology has been successfully applied to the reservoir stimulation of Fan Ye 1 well horizontal well in Jiyang Depression, improving the energy utilization efficiency of hydraulic fracturing and reducing carbon emissions.

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BibTeXRIS

Cheng Cheng. 2023-08-28. Energy-Efficient Fracturing Based on Stress-Coupled Perforation. https://arxiv.org/abs/2309.03997

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