| 摘要: |
| 目的 水合物法封存CO2,具有良好的稳定性和高的储气密度,是目前最有潜力的一种碳封存方式之一,其中利用冻土区的地层条件更具独特优势。将CO2气体注入冻土区地层中,在一定的温度压力条件下形成固态CO2水合物实现封存。方法 依据我国冻土地区地层深度对应的温度和压力条件,选取不同地层深度(150和200 m)对应温度(1.27和2.72 ℃)和有效孔隙含水率40%,研究不同注入压力(3.50、4.50和5.50 MPa)的封存特征。分析封存过程的温度压力变化、封存速率、最终水转化率和最终封存率等动力学规律。结果 封存压力越高,水合物法封存所需的诱导时间越短,压力降幅越大。较高的封存压力,在初期封存速度较慢,且缓慢封存期的持续时间减少。且封存压力越高,封存率、最终水转化率和水合物相饱和度越高。封存温度越高,压力对封存率的影响效果越明显。结论 在地层深度150 m(对应地层平均温度1.27 ℃)和5.50 MPa条件下CO2封存效果最佳。 |
| 关键词: 冻土区 水合物 CO2 封存 注入压力 |
| DOI： |
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| 基金项目:太原科技大学科研启动基金（20232107）；博士后面上71批基金（2022M712337）；山西省回国留学人员科研资助项目（2020-046） |
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| Experimental study of CO2 sequestration using hydrate method under various pressures in permafrostGao Qiang1, 2, Zhao Jianzhong2, Hou Bin2, Zhang Chi2 |
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高强1, Taiyuan2, Shanxi2, China2
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1.Taiyuan University of Science and Technology;2.Key Laboratory of In-situ Property-improving Mining of Ministry of Education,Taiyuan University of Technology,Taiyuan,Shanxi,China
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| Abstract: |
| Objective CO2 sequestration via hydrate method is one of the potential carbon sequestration methods because of its stability and high gas storage rate. The use of formation conditions in permafrost has more unique advantages. CO2 is injected into the permafrost region, and CO2 hydrate is formed under certain temperature and pressure conditions to achieve long-term stable storage. Methods According to the temperature and pressure conditions of the formation in the permafrost region of China, the temperature (1.27 and 2.72 °C) and effective pore water content (40 %) corresponding to different formation depths (150 and 200 m) and different initial injection pressures (3.50, 4.50 and 5.50 MPa) were selected. The characteristics of kinetic parameters such as temperature and pressure changes, storage rate, final water conversion rate and final storage rate in the CO2 storage process via hydrate method were analyzed. Results The results of CO2 hydrate sequestration process under different initial injection pressures show that the higher the initial injection pressure, the shorter the induction time required for hydrate generation and the larger the pressure drop. Higher injection pressure results in slower generation rate at the initial stage and reduced duration of slow generation period. The higher the injection pressure, the higher the hydrate sequestration rate, the higher the final water conversion rate, and the higher the final hydrate phase saturation at the end of the reaction. The higher the experimental temperature, the more obvious the effect of pressure on the gas sequestration rate. Conclusion The best CO2 sequestration effect was achieved under the condition of 40% water content at the depth of 150 m (the average temperature of the formation is 1.27 ℃) and 5.50 MPa. |
| Key words: permafrost region hydrate CO2 sequestration injection pressure |
