摘要
为探究CO2埋地管道泄漏对土壤区热力特性的影响,依托DN250、长260 m的工业级试验管道,搭建了DN100规格埋地管道泄漏试验装置,通过设置4个不同孔径和开孔方向的泄漏孔,对超临界CO2埋地管道泄漏时的土壤形貌及土壤区温度变化情况进行了分析。结果表明:土壤区会形成冻土球,由外向内分为冻土层和干冰球两部分;干冰球内部存在冲击空腔,其外表面布满凹坑;3 mm孔径泄漏生成干冰球体积是1 mm孔径泄漏的5.5倍;水平和顶部泄漏试验生成干冰球体积接近,约为底部泄漏的1.9倍;总结了干冰球增长过程,干冰球高度与时间满足正弦函数和指数函数关系;3 mm泄漏土壤区温降起始时刻比1 mm泄漏早,前者温降速度是后者的50倍。
The paper is oriented to explore the soil thermal change in case the CO2 buried pipeline would be leaked through.To simulate the actual buried situation,a buried leakage device(in nominal diameter of 100 mm)in different orifice diameters and directions(diameter 3 mm for horizontal,top,bottom respectively and diameter 1 mm for horizontal)based on the industrial scale CO2 one(of 260 m in length,with its nominal diameter of 260 mm)was established herein.And the influence of the orifice diameters and directions on the soil morphology and temperature through leakage experiment of the supercritical CO2 pipeline buried underneath was analyzed.The results showed that a frozen soil ball which consisted of a stratum of frozen earth outside and a dry ice ball inside would be formulated in the soil area.There was an impact-cavity in the interior of the dry ice ball.The outer surface of the dry ice ball was pockmarked with pits,whereas the volume of the dry ice ball generated by the 3 mm leakage experiment was proven in a size 5.5 times through the 1 mm leakage experiment.In addition,the volumes of the dry ice ball generated by the horizontal and upward leakage experiments could be approximately proven to be equal,with 1.9 times as that of the downward leakage experiment.As to the growth process of the frozen soil ball,it could be divided into 3 stages,known as the augmentation-stabilization-and-again-augmentation.In the first stage,the growth rate of the height was2.3 times of the third stage.And,moreover,in the first stage,the relationship between the dry ice height and time was in the sine function.But in the 3-rd stage,the relation between the dry ice height and the time tended to be in an exponential function.That is,the horizontal leakage experiment with 3 mm orifice diameter could likely be getting to start earlier with a faster temperature down-drop than the horizontal leakage with 1 mm orifice.And,in such a situation,the temperature drop pace of the 3 mm leakage experiment could be turned to be up to 50 times that of
作者
喻健良
于帅
闫兴清
曹琦
闫振汉
YU Jian-liang;YU Shuai;YAN Xing-qing;CAO Qi;YAN Zhen-han(School of Chemical Engineering,Dalian University of Technology,Dalian 116024,Liaoning,China;School of Mechanical and Electrical Engineering,Jilin Institute of Chemical Technology,Jilin 132000,Jilin,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2021年第5期1963-1970,共8页
Journal of Safety and Environment
关键词
安全工程
埋地管道
泄漏
超临界CO_(2)
土壤形貌
温度
safety engineering
buried pipeline
leakage
supercritical CO_(2)
soil morphology
temperature
