高温高压下C_(3)H_(8)/C_(2)H_(4)在空气中的爆炸上限

The upper explosion limit of C_(3)H_(8)/C_(2)H_(4)mixtures in air at high temperatures and pressures

为了防控高温高压工艺流程中可燃混合气体潜在的爆炸风险,利用自行搭建的20 L球形爆炸特性实验装置,测试了初始温度20~200℃、初始压力0.1~1.5 MPa下C_(3)H_(8)/C_(2)H_(4)混合气体在空气中的爆炸上限,分析了温度、压力和C_(2)H_(4)体积分数对混合气体爆炸上限的影响。结果表明,随着温度和压力的升高,C_(3)H_(8)/C_(2)H_(4)混合气体爆炸上限升高。当初始压力高于0.3 MPa时,随着C_(2)H_(4)体积分数的增加,爆炸上限的上升速率明显降低。随着C_(2)H_(4)体积分数的增加,高温和高压下爆炸上限的提升幅度和速率比常温常压下更高。温度和压力的协同作用对爆炸上限的影响远大于二者单独作用的影响之和,即高温和高压协同作用下,C_(3)H_(8)/C_(2)H_(4)混合气体具有更高的爆炸风险,且随着C_(2)H_(4)体积分数的增加,爆炸风险会进一步提升。分别拟合得到了爆炸上限与温度参数、爆炸上限与压力参数以及爆炸上限与温度和压力双参数下的函数关系。

It is necessary to understand the upper explosion limits of C_(3)H_(8)/C_(2)H_(4)mixtures to prevent the potential explosive risks of flammable gas mixtures in the process of high temperatures and pressures.An experimental device of a 20 L spherical vessel with high pressure placed in a high-temperature oven was set up to test the upper explosion limits of C_(3)H_(8)/C_(2)H_(4)mixtures at high pressure and temperature.The partial pressure method was used to prepare the mixtures of C3H8,C_(2)H_(4),and air with a certain concentration.A pressure rise amplitude of 5%was adopted to judge whether the explosion occurred.The initial temperature ranged from 20℃to 200℃,and the initial pressure ranged from 0.1 MPa to 1.5 MPa in the experiments.The effects of temperature,pressure,and volume fraction of C_(2)H_(4)on the upper explosion limit of C_(3)H_(8)/C_(2)H_(4)mixtures were analyzed.The results show that the upper explosion limit of C_(3)H_(8)/C_(2)H_(4)mixtures increases with the rises of temperature and pressure,but the increase rate of the upper explosion limit decreases significantly with the increase of C_(2)H_(4)concentration when the initial pressure is higher than 0.3 MPa.The amplitude increase and rate of the upper explosion limit with C_(2)H_(4)at high temperatures and pressures are higher than those at normal conditions.The influences of temperature and pressure on the upper explosion limit are much greater than the sum of the two effects alone,indicating that the C_(3)H_(8)/C_(2)H_(4)mixtures have a higher explosion risk under the synergistic effect of high temperature and pressure,and it will be further enhanced with the increase of C_(2)H_(4)concentration.The influence of the temperature,pressure,and their synergistic effects on the upper explosion limit of C_(3)H_(8)/C_(2)H_(4)mixtures in different proportions are comprehensively analyzed,and the corresponding functional relations of the temperature-upper explosion limit,pressure-upper explosion limit,and temperature-pressure-upper explosion limit in different volume fractions of C_(2)H_(4)are summarized by the non-linear regression of surface.