Simulation of CO2 capture using MEA scrubbing: a flowsheet decomposition method
Simulation of CO2 capture using MEA scrubbing: a flowsheet decomposition method
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DOI：
10.1016/j.enconman.2004.03.003
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发表时间：
2005-02
影响因子：
10.4
通讯作者：
Colin F. Alie;L. Backham;E. Croiset;P. Douglas
中科院分区：
文献类型：
--
作者：
Colin F. Alie;L. Backham;E. Croiset;P. Douglas
从技术上讲，利用单乙醇胺（MEA）吸收工艺从天然气/燃煤电厂的烟气中捕集二氧化碳，是减少大型点源大气二氧化碳排放的一项可行的中短期战略。然而，这种系统的成本目前被认为太高，在经济上不可行。一个实际的研究目标是分析二氧化碳捕获过程，以期将实施成本降至最低。由于大规模的二氧化碳捕获操作是昂贵的，过程模拟和建模在评估过程替代方案方面发挥着重要作用。在胺洗涤的情况下，由于该过程的高度非线性性质和涉及的大型循环流，工艺流程图的收敛是一项重要的工作。本文提出了一种分解工艺流程的方法，该方法有助于收敛工艺流程和优化关键工艺操作变量，特别是进入汽提塔的MEA的胺负荷和温度。该方法应用于三种不同的co2浓度（摩尔分数，湿基）：3%（模拟燃气轮机的烟气）、14%（燃煤厂的烟气）和25%（水泥厂的烟气）。该分解方法可用于研究吸收塔和汽提塔的工艺参数。解耦流程的结果为集成流程的收敛性提供了良好的初始估计。解耦和集成流程的结果相似。对于所研究的所有co2浓度，在低MEA负荷为0.25时，再沸器负荷最小。
Technically, the capture of CO2from the flue gas of natural gas/coal fired power plants, using a monoethanolamine (MEA) absorption process is a viable short to medium term strategy for mitigation of the atmospheric CO2emissions from large point sources. The costs, however, of such systems are currently perceived to be too high to be economically feasible. A practical research objective is the analysis of the CO2capture process with a view towards minimizing the cost of implementation. Because large scale CO2capture operations are expensive, process simulation and modelling have an important role to play in evaluation of the process alternatives. In the case of amine scrubbing, the convergence of the process flow sheet is a nontrivial exercise due to the highly nonlinear nature of the process and the large recycle stream involved. This paper presents a method of decomposing the flow sheet that assists in converging the process flow sheet and in optimizing key process operating variables, in particular the amine loadings and temperature of MEA entering the stripper. This method was applied to three different CO2concentrations (molar fraction, wet basis): 3% (to simulate flue gas from a gas turbine), 14% (flue gas from a coal plant) and 25% (flue gas from a cement plant). The decomposition method proved useful for investigation of the process parameters in both the absorber and the stripper. The results from the decoupled flow sheet provided good initial estimates for the convergence of the integrated flow sheet. The results from the decoupled and integrated flow sheets were similar. A minimum reboiler duty was found at a lean MEA loading of 0.25 for all CO2concentrations studied.