Soil temperature field around buried carbon dioxide pipelines under different transport phases
In order to study the distribution law of the soil temperature field around the buried carbon dioxide pipeline,a numerical model of the soil temperature field around the pipeline was established based on the carbon dioxide transportation pipeline of million-ton carbon capture,utilization and storage(CCUS)demonstration project of Qilu Petrochemical Company-Shengli Oilfield.The soil temperature field in typical conditions under three transport phases of carbon dioxide(low-pressure liquid phase,high-pressure liquid phase,and supercritical phase)was calculated by Fluent software.On the basis of low-pressure liquid phase transportation,the seasonal variation of the soil freezing range around the pipeline and the influence of different buried depths and different operating temperatures on the soil freezing range around the pipeline were analyzed.The results show that with the increase in buried depth,the range of permafrost around the pipeline increases,and the range of seasonal frozen soil is less affected.With the increase in the starting temperature,the range of permafrost and seasonal frozen soil around the pipeline decreases,and frozen soil will no longer form when the temperature rises to 0℃.On the basis of high-pressure liquid phase transportation and supercritical transportation,the influence of the operating temperature of the pipeline on surface vegetation is analyzed,with wheat as an example.The results show that to make the soil temperature meet the growth requirements of crops along the pipeline,the medium temperature should not be lower than 5℃during high-pressure liquid phase transportation of carbon dioxide and should not be higher than 50℃during supercritical transportation.
carbon dioxide pipelinesoil temperature fieldCCUSnumerical simulation