甲醇-乙酸酐体系的热分解特性及安全泄放

Thermal decomposition and safety relief for methanol-acetic anhydride system

安全泄放是在失控条件下降低反应体系风险最为经济有效的技术措施之一。为了研究泄放口的设计,利用高性能绝热量热仪Phi-TECⅡ对质量分数38.6%的甲醇-乙酸酐体系进行了测试,得到热惯量为1.1条件下该体系的热行为参数。测试结果表明,该体系的起始分解温度为37℃,比反应热205.2 kJ·kg-1;拟合得到温度与压力的关系基本符合Antoine方程,确定了反应体系的泄放类型属蒸汽体系;采用Leung方法和平衡速率模型ERM对该体系的安全泄放量和泄放能力进行了计算,求得泄放面积为1.36×10-3 m2;低热惯量的Phi-TECⅡ可以为工艺放大的泄放设计提供准确、可靠的基础数据。

Emergency relief systems for reducing risk of runaway reactions are being used as one of the most cost-effective technical measures. Therefore, in order to design the pressure relief system sizing, research on a 38.6% methanol-acetic anhydride was carried out based on the bench-scale Phi-TEC II calorimeter apparatus. Parameters of thermal behavior were measured with thermal inertia 1.1. Results show that self-heating decomposition temperature tends to be around 37℃, with its corrective heat of the reaction being 205.2 kJ . kg-1. The fitting equation obtained from experimental data is basically in accord with Antoine equation. The reactive system can be identified as a vapor system. The mass flow capacity and the average two-dimensional flowing capacity per cross-section unit area of the vent-line were determined by Leung＇s method and ERM. Thus, the required relief area was determined to be 1.36× 10-3 m2. Thus, it is proved that the Phi-TEC II calorimeter can be used to supply the basic runaway chemical reaction data and in turn provide technical supports for the emergency relief system, which is helpful to improve the reliability of the safety relief design.