精馏塔与热口袋的集成优化可以进一步回收利用过程中的能量,当塔的热负荷大于热口袋所能提供的热负荷时,可以通过调整,增加中间换热器实现与热口袋的热集成。中间换热一般使用精馏塔与背景过程两者的总复合曲线(即温焓图)进行分析,但温焓图(T-H图)无法直接看出中间换热物流合适的抽出位置,不能使热集成达到最优化。故本文通过对某乙二醇装置的C08MEG塔进行全塔模拟,针对不同的中间换热工况,采用板焓图(Stage—H图)进行分析,最终确定了中间换热器的最优位置及负荷,使热集成的节能效益更显著。
Heat integration of distillation columns and heat pockets can further save energy of processes. When the heat load of tower is greater than that provided by heat pockets, adding inter-heat exchangers can achieve heat integration. Generally, temperature-enthalpy is used to analyze intermediate heat transfer. But we can't directly know the optimal position of inter-heat exchangers. Then heat integration can't achieve optimization. Therefore, for different intermediate heat transfer conditions, the use of stage-enthalpy is analyzed in this paper. Through the simulation of C08MEG tower of an ethylene glycol plant, we finally determine the optimal position and heat duty of the inter-heat exchanger, which make the effect of energy-saving more remarkable.