油页岩原位开采井下燃烧加热器催化燃烧特性及参数优化研究

Study on catalytic combustion characteristics and parameter optimization of underground combustion heaters for in-situ oil shale extraction

摘要:

针对油页岩原位转化开采过程中的环境污染与能源效率问题，本研究提出一种将井下开采产生的甲烷废气回收，并用于催化燃烧加热器的能源循环利用方法。研究选定催化燃烧与多孔介质燃烧相结合的方式，以甲烷为燃料，构建二维轴对称模型，系统模拟了孔径、注气速率及甲烷摩尔分数对燃烧效果的影响。研究结果表明：减小孔径可显著提高甲烷转化率与尾气温度；注气速率的变化对燃烧效果影响微弱；贫燃状态下甲烷浓度的微量变化对转化率提升有限。本研究为油页岩井下废气中甲烷的资源化利用与燃烧加热器的优化设计提供了理论依据，对推动油页岩绿色开采具有重要的工程参考价值。

Abstract:

To address the issues of environmental pollution and energy efficiency in the in-situ conversion and exploitation of oil shale， this study proposes an energy recycling method that involves recovering methane-rich waste gas generated from the downhole process and utilizing it as a fuel for a catalytic combustion heater. In this research， a combined approach of catalytic combustion and porous medium combustion was adopted， with methane as the fuel. A two-dimensional axisymmetric model was constructed to systematically simulate the effects of pore diameter， gas injection rate， and methane mole fraction on combustion performance. The results indicate that： reducing the pore diameter can significantly enhance methane conversion rate and exhaust gas temperature； variation in the gas injection rate has a negligible impact on combustion performance； under fuel-lean conditions， minor changes in methane concentration lead to limited improvement in the conversion rate. This study provides a theoretical basis for the resource utilization of methane from downhole waste gas in oil shale operations and the optimized design of combustion heaters， offering significant engineering reference value for advancing the green extraction of oil shale.