穿越公路埋地长输管道在冻土区的热力变形规律研究

Study on Thermal Deformation Law of Long Distance Pipeline Buried in Highway Permafrost Region

基于某穿越公路埋地原油管道工程,对其在冻土区的热力变形规律进行了研究,结果表明,冻土类型不同,在管道周围,土壤温度场具有较大差异,管道对高温冻土区的热油管道具有较大影响,对冻土有较大破坏;在高温冻土区,其融化速率均大于低温冻土区;通过保温材料的铺设,高温冻土区的最大融化深度可得到有效减小。在高温冻土区,减小管道顶部埋置深度,管道底部的最大融化深度可有效减小,对冻土区效果更好。随着时间的延长,外层等温线距管道中心的距离变化较小,且由于管道向外不断进行热量散发,最外层温度会逐渐升高,保温层越厚,冻土受到铺设输油管道的破坏性越小。通常情况下保温层铺设厚度为5.2-8.2cm,在高温冻土区,管道对其扰动较大,保温层大于8.2 cm时,在热油管道外铺设保温材料,减少管内油品热量损失,减少管道对冻土的扰动,确保管道安全运行,同时将输送成本降低。

In this paper,a road crossing buried oil pipeline project based on the deformation law of the heat in permafrost area were studied,the results show that the permafrost types around the pipeline,soil temperature field has great difference,has a great influence on the oil pipeline pipeline in high-temperature permafrost regions,there is a great damage to the permafrost in high temperature permafrost; the area was greater than the melting rate of low-temperature regions; the thermal insulation material of laying,the maximum thawing depth in high temperature permafrost area can be reduced effectively. In the permafrost zone,the maximum depth of melting at the bottom of the pipeline can be effectively reduced and the effect is better for the frozen soil area,because the buried depth of the pipe top is reduced. With the extension of time,distance from the center of the pipe outer change isotherm is small,and because of a pipeline to continuously heat dissipation,the outer temperature will gradually increase,the insulation layer is thicker,frozen by the destructive laying of oil pipeline is small. Usually the laying of insulation layer thickness is 5. 2 ~ 8. 2 cm,in high temperature permafrost zone,pipeline greater disturbance on the insulation layer is larger than 8. 2 cm,the insulation material in the hot oil pipeline,reducing oil loss of heat pipe,reducing pipe disturbance on permafrost,ensure the safe operation of the pipeline,and will reduce the transportation cost.