埋地天然气管道泄漏量计算与分析

为计算埋地天然气管道泄漏量,获得合理的埋地管道泄漏计算模型与埋地管道土中天然气吸收量,通过分析燃气管道泄漏的模型划分标准,建立等温与等熵模型计算小孔泄漏量。结合天然气管线泄漏强度的实验数据进行对比分析,得出了等熵与等温模型分别为实际小孔泄漏量的上下限;利用菲克定律推导埋地管道泄漏扩散浓度方程,并分析扩散范围,结合工程实例对泄漏量进行计算分析。研究结果表明,小孔泄漏孔径越小,处于爆炸浓度极限的时间越长,危险性越高。根据埋地管道周围土中各点天然气浓度分布规律,提出了土壤吸收量计算方法,改进了地面蒸气云泄漏质量计算方法,结合工程实例定量地给出了土壤的天然气吸收率。

Calculation and analysis of buried gas pipeline leakage

To calculate the leakage rate of gas pipeline, the reasonable calculation model of buried pipeline leakage and the amount of natural gas absorption were proposed. The isothermal and isentropic models were established by the model classification of gas pipeline leakage to calculate the leakage of small hole, and the experimental data of leakage of gas pipeline obtained by comparative analysis. The isothermal and isentropic models are the upper and lower limits of actual leakage of small holes, respectively. Ficks Model was used to deduce the equation of buried pipeline leakage concentration and calculate the leakage combining with the actual engineering. The smaller the hole, the longer the explosion concentration limit, which causes higher risk. According to the concentration distribution of each point in the soil, the calculation of absorption capacity was proposed. Combining with project case, the calculation method of surface vapor cloud leakage was improved, and the gas absorption rate of natural gas was given.