高温和高压对乙烷在氧气中爆炸极限影响的实验研究

Experimental study on the influence of high temperature and high pressure on the upper limit of explosion of ethane in oxygen

获得高温、高压下可燃介质爆炸极限数值,对完善复杂工况下可燃介质燃爆安全理论、构建可燃介质爆炸防护技术提供支持。搭建了适用于开展高温、高压工况的20 L球形爆炸实验装置,测量了初始温度为20~270℃,初始压力为0.5~2.6 MPa下乙烷在氧气中的爆炸极限,分析温度、压力单因素对乙烷在氧气中的爆炸极限的影响以及温度和压力双因素的耦合影响。结果表明,随着初始压力和初始温度的提高,乙烷在氧气中的爆炸极限逐渐扩大。在温度小于140℃时,在高压和低压两种情况下,压力对乙烷爆炸上限的影响基本一致。在温度高于140℃时,压力的升高使乙烷爆炸上限升高,但其影响的效果逐渐减小。在初始压力小于1.6 MPa时,温度的升高使乙烷的爆炸上限升高,但其影响的效果变化很小。在压力大于1.6 MPa,温度高于140℃时,温度的升高使乙烷的爆炸上限升高,且其影响的效果逐渐增大。温度和压力的升高均使乙烷的爆炸下限降低,但其影响较小。初始温度和初始压力对乙烷在氧气中爆炸极限的耦合作用略小于两个因素作用的和,但大于单个因素的作用。通过拟合得到了C2H6/O2爆炸极限随初始压力、初始温度变化的定量规律。

The explosion limits of combustible material at elevated temperatures and pressures provide support for perfecting fire and explosion safety theory and improving explosion protection technology.A closed 20 L spherical vessel was designed to measure the explosion limits under abnormal conditions.The explosion limits of ethane/oxygen mixtures at temperatures ranging from 20 to 270°C and pressures ranging from 0.5 to 2.6 MPa were measured.The influence of temperature,pressure and their coupling effect on the explosion limits in oxygen were analyzed.The results showed that the range of the explosion limits of ethane in oxygen gradually widened as the initial pressures and temperatures increased;the UELs in oxygen changed almost linearly when the initial temperatures were below 140°C;as the temperature continues to rise,its effect gradually decreased;the UELs in oxygen changed almost linearly when the initial temperatures were below 140°C;the UELs in oxygen linearly increased when the initial pressures were below 1.6 MPa;the rising rate of UEL increased above 1.6 MPa and 140°C;the elevated temperatures and pressures decreased the LELs of ethane in oxygen,but their effect was reduced;the coupling effect of the initial temperatures and pressures on the explosion limits of ethane/oxygen mixtures was found slightly less than the sum of the two factors,but far greater than the effect of each individual factor;and the quantitative rules of explosion limits varying with the initial pressures and temperatures were obtained using the fitting formula.