利用Aspen Plus ActiveX自動化伺服器進行萃取蒸餾塔的最適化

Abstract

運用連續式萃取蒸餾的方法進行共沸混合物分離，其中流程的設計和優化對年總成本有顯著影響。針對這些問題，本研究應用模擬退火演算法進行最適化設計，並且整合了商用模擬軟體（Aspen Plus）來建立萃取蒸餾的模型，在模擬退火演算法跟商用模擬軟體之間的連接介面是採用具有優化相關功能的MATLAB,並且選取三組有代表性的共沸體系運用此法進行分離。 對丙酮和甲醇（Acetone-methanol system）混合物分離的結果顯示優於常規優化方法的結果。對於正己烷和乙酸乙酯（N-hexane-ethyl acetate system）共沸物系統，比較了N-甲基吡咯烷酮(NMP），2-甲基吡啶，3-甲基吡啶，二甲基甲醯胺（DMF），吡咯作為萃取劑時的年總成本，在產品的純度設定為99.5mol％的條件下，DMF具有性能和經濟效益優勢。對於正己烷和四氫呋喃（N-hexane-THF system）共沸物系統，比較了DMF，NMP，2-甲基吡啶作為萃取劑，在產品的純度均為99.5mol％時，DMF是最合適的萃取劑。 結果表明，該方法能成功分離出這些共沸混合物，優化年總成本，並且具有提高獲得全域最優的概率和減少計算時間的優點，該方法可以成為其他複雜蒸餾系統的一般適用方法。

In this paper, continuous extractive distillation was used to separate azeotropic mixtures. The design and optimization have a critical impact on its total annual cost. An optimization method that integrates simulated annealing algorithm, the simulation software Aspen Plus and the optimization-related features of MATLAB was proposed. We then programmed the continuous-running SA method to optimize three cases of extractive distillation. For the acetone-methanol case, the TAC of using different entrainers are much lower when compared with conventional optimization method. For the n-hexane-ethyl acetate system, the candidate entrainers are NMP, 2-methylpyridine, 3-methylpyridine, DMF, pyrrole. In this case, purities of the products are set at 99.5mol%. Results show that DMF has performance and economic benefit. For n-hexane-tetrahydrofuran system, the candidate entrainers are DMF, NMP, 2-methylpyridine. Also, all products’ purities are set at 99.5mol%. DMF is the most suitable entrainer. These azeotropic mixtures were separated successfully with this method. Results show that the continuous-running simulation has the advantage of a high probability to obtain the global optimum and less computing time. This method may become a generally applicable method for other complicated distillation systems.