针对目前甲苯二异氰酸酯(TDI)生产过程中光化第二回收塔存在邻二氯苯(ODCB)含量超标问题,以某化工厂TDI含ODCB废水为研究对象,建立第二ODCB回收塔分离工艺。借助Aspen Plus V11流程模拟软件对第二ODCB回收塔精馏过程进行稳态模拟和计算...针对目前甲苯二异氰酸酯(TDI)生产过程中光化第二回收塔存在邻二氯苯(ODCB)含量超标问题,以某化工厂TDI含ODCB废水为研究对象,建立第二ODCB回收塔分离工艺。借助Aspen Plus V11流程模拟软件对第二ODCB回收塔精馏过程进行稳态模拟和计算,以确定最优进料位置、理论塔板数和回流比。对7万t和5万t回收塔模拟计算结果进行物料衡算后发现,塔釜中基本没有ODCB存在,ODCB都在塔顶。基于流程模拟、物料平衡分析和实验验证,第二回收塔分离工艺的最优进料位置为第5块塔板,理论塔板数为13,回流比为1.0,最终TDI质量分数大于99.80%,ODCB质量分数小于0.02%,同时蒸汽消耗量降低,开车后连续3个月运行稳定。展开更多
Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application ...Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application in the future,the thermal stability of this substance during storage,transportation,and use will become quite important.Thus,in this work,the thermal decomposition behavior,thermal decomposition kinetics,and thermal hazard of ADCA were investigated.Experiments were conducted by using a SENSYS evo DSC device.A combination of differential iso-conversion method,compensation parameter method,and nonlinear fitting evaluation were also used to analyze thermal kinetics and mechanism of ADCA decomposition.The results show that when conversion rate α increases,the activation energies of ADCA's first and main decomposition peaks fall.The amount of heat released during decomposition varies between 182.46 and 231.16 J·g^(-1).The proposed kinetic equation is based on the Avrami-Erofeev model,which is consistent with the decomposition progress.Applying the Frank-Kamenetskii model,a calculated self-accelerating decomposition temperature of 287.0℃is obtained.展开更多
文摘针对目前甲苯二异氰酸酯(TDI)生产过程中光化第二回收塔存在邻二氯苯(ODCB)含量超标问题,以某化工厂TDI含ODCB废水为研究对象,建立第二ODCB回收塔分离工艺。借助Aspen Plus V11流程模拟软件对第二ODCB回收塔精馏过程进行稳态模拟和计算,以确定最优进料位置、理论塔板数和回流比。对7万t和5万t回收塔模拟计算结果进行物料衡算后发现,塔釜中基本没有ODCB存在,ODCB都在塔顶。基于流程模拟、物料平衡分析和实验验证,第二回收塔分离工艺的最优进料位置为第5块塔板,理论塔板数为13,回流比为1.0,最终TDI质量分数大于99.80%,ODCB质量分数小于0.02%,同时蒸汽消耗量降低,开车后连续3个月运行稳定。
基金supported by National Natural Science Foundation of China(51974166).
文摘Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application in the future,the thermal stability of this substance during storage,transportation,and use will become quite important.Thus,in this work,the thermal decomposition behavior,thermal decomposition kinetics,and thermal hazard of ADCA were investigated.Experiments were conducted by using a SENSYS evo DSC device.A combination of differential iso-conversion method,compensation parameter method,and nonlinear fitting evaluation were also used to analyze thermal kinetics and mechanism of ADCA decomposition.The results show that when conversion rate α increases,the activation energies of ADCA's first and main decomposition peaks fall.The amount of heat released during decomposition varies between 182.46 and 231.16 J·g^(-1).The proposed kinetic equation is based on the Avrami-Erofeev model,which is consistent with the decomposition progress.Applying the Frank-Kamenetskii model,a calculated self-accelerating decomposition temperature of 287.0℃is obtained.
