Open Access

ARTICLE

An Integrated Optimization Method for CO₂ Pre-Injection during Hydraulic Fracturing in Heavy Oil Reservoirs

by Hong Dong¹, Xiding Gao^2,*, Xinqi Zhang¹, Qian Wang^1,3, Haipeng Xu¹, Binrui Wang², Chengguo Gao¹, Kaiwen Luo², Hengyi Jiang²

1 PetroChina Xinjiang Oilfield Company, Karamay, 834000, China
2 National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, China
3 Department of Modern Mechanics, University of Science and Technology of China, Hefei, 230026, China

* Corresponding Author: Xiding Gao. Email:

Fluid Dynamics & Materials Processing 2024, 20(9), 1971-1991. https://doi.org/10.32604/fdmp.2024.049406

Received 06 January 2024; Accepted 11 March 2024; Issue published 23 August 2024

Abstract

CO₂ pre-injection during hydraulic fracturing is an important method for the development of medium to deep heavy oil reservoirs. It reduces the interfacial tension and viscosity of crude oil, enhances its flowability, maintains reservoir pressure, and increases reservoir drainage capacity. Taking the Badaowan Formation as an example, in this study a detailed three-dimensional geomechanical model based on static data from well logging interpretations is elaborated, which can take into account both vertical and horizontal geological variations and mechanical characteristics. A comprehensive analysis of the impact of key construction parameters on Pre-CO₂ based fracturing (such as cluster spacing and injection volume), is therefore conducted. Thereafter, using optimized construction parameters, a non-structured grid for dynamic development prediction is introduced, and the capacity variations of different production scenarios are assessed. On the basis of the simulation results, reasonable fracturing parameters are finally determined, including cluster spacing, fracturing fluid volume, proppant concentration, and well spacing.

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Keywords

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