胺法脱碳系统再生能耗

Heat requirement for regeneration of a CO_2 capture system using amine solutions

胺法脱碳系统最大的缺陷是再生能耗高,流程参数优化是降低再生能耗的有效途径。为了解再生操作参数对再生能耗的影响,通过再生塔实验台对醇胺吸收剂在不同再生工艺参数下的再生特性进行实验研究。实验内容包括富液CO2担载量、富液进料温度、再沸器温度、再生压强及胺的种类因素对再生能耗及再生速率的影响,并分析了显热、潜热的变化规律。应用Aspen Plus基于速率模型对再生过程进行了模拟研究。研究结果表明:提高富液CO2担载量和富液进料温度能有效降低再生能耗。增大再沸器温度及再生压强反而增大再生能耗。一乙醇胺(MEA)再生能耗较高,混入甲基二乙醇胺(MDEA)能够显著降低能耗。提高富液CO2担载量和再沸器的温度可以加快CO2再生速率。

The main drawback of amine-based CO2 capture system is high heat requirement for the solvent regeneration.The optimization of the process parameters is an effective way to break this limitation.In this paper,the experiments are carried out to investigate the stripper performance under diverse parameters of regeneration process,including the effects of CO2 loading and feeding temperature of rich-solutions,reboiler temperature,regeneration pressure and alkanolamine type.The changes of sensible heat and heat of vaporization were analyzed.A rate-based model in Aspen Plus simulator was used to simulate the regeneration process.The results show that the heat requirement for the regeneration can be reduced by using higher CO2 loading and feeding temperature of rich-solutions,while the heat requirement for regeneration increased with increasing reboiler temperature and regeneration pressure.The regeneration heat of monoethanolamine（MEA）is quite high,and can be reduced by blending methyldiethanolamine（MDEA）.The CO2 desorption rate increased with the CO2 loading of rich solution and reboiler temperature.