为了避免航空煤油在高热流条件下主动热防护过程中的结焦沉积,需要对航空煤油的热裂解和结焦沉积反应规律进行研究.通过考察航空煤油在不同反应条件下气液相产物以及结焦量,对航空煤油的热裂解结焦反应规律展开实验研究.结果表明:航空煤油中的烯烃组分的二聚反应和芳香烃的缩聚反应是导致结焦的重要反应.随着温度的升高,航空煤油的热裂解程度加剧,且主要结焦反应速率加快,因此航空煤油的结焦量随之上升,甲烷、乙烯等小分子气相产物体积分数也随之升高,液相产物中烷烃质量分数明显下降,芳香烃质量分数上升.压力的升高会导致工质在板内的停留时间增加,从而使得结焦反应更多的朝正反应移动,所以液相产物中芳香烃质量分数随压力的升高而明显增多.
To reduce the coke deposition of aviation kerosene in the process of active thermal protection,some reaction principles of thermal cracking and coke deposition should be investigated.Thermal cracking and coke experiments were conducted to compare the difference of gaseous,liquid and coke amount under different conditions.The results showed that dimerization of olefins and condensation polymerization of aromatics were the main reactions in the coke process.With the enhancement of temperature,the reaction rates of dimerization and polymerization sped up,so the coke amount in the reactor was aggravated.Volumn fraction of gas products such as methane and ethylene increased.In the liquid products,mass fraction of alkane decreased but the aromatics mass fraction increased.The residence time of kerosene increased significantly with the growth of pressure,benefiting the coke formation and additional aromatics in the liquid products.