基于甲烷催化燃烧的油页岩原位开采技术研究

Research on in-situ oil shale extraction technology based on methane catalytic combustion

摘要:

针对油页岩开采过程中产生的含甲烷废气，提出了一项创新性的技术方案，即利用含低浓度甲烷裂解气进行催化燃烧以促进油页岩的开采，并借助Fluent和CMG软件进行了详尽的模拟分析。Fluent模拟研究发现，较小的孔径和增加的催化段长度能有效提升甲烷的转化率和燃烧温度，甲烷转化率可达到92.4%的高值，尾气温度亦可达到1050 K。CMG模拟结果显示，在不同的甲烷转化率条件下，油页岩开采过程中的温度场分布及油气产量存在显著差异，甲烷转化率92%时总产油量最高，为20.5 m3；同时，随着转化率的降低，日产气量呈现上升趋势，且峰值出现时间提前。研究证实了该方案在实现废气循环利用、提升能源利用效率的同时，还能有效减轻环境负担，为油页岩的绿色、高效开采提供了崭新的技术路径和方法。

Abstract:

In this study， for the methane-containing waste gas generated during the oil shale extraction process， an innovative technological solution， i.e.， catalytic combustion using methane cracking gas containing low concentration of methane to facilitate oil shale extraction， was proposed and analysed by means of detailed simulations with the help of Fluent and CMG software. In Fluent simulation， the role of pore size and length of porous media on the efficiency of catalytic combustion was explored. It is found that smaller pore size and increased catalytic section length could effectively enhance the methane conversion rate and combustion temperature. After model optimisation， the methane conversion rate can reach a high value of 92.4%， and the tail gas temperature can reach 1050 K. The CMG simulation results show that there are significant differences in the temperature field distribution and oil and gas production during the oil shale extraction process under different methane conversion rate conditions. The total oil production reaches the highest value of 20.5 m3 at a methane conversion rate of 92%. Meanwhile， the daily gas production shows an increasing trend with the decrease of the conversion rate， and the peak appears earlier. The study confirms that the scheme can effectively reduce the environmental burden while realising the recycling of waste gas and improving the efficiency of energy use， providing a brand new technical path and methodology for the green and efficient exploitation of oil shale.