ASPEN sensitivity study for the Great Plains Gasification Plant rectisol section

A previously developed ASPEN model of the Rectisol portion of the Great Plains Plant has been extensively revised to more closely represent the as-built plant as reflected by the plant control (PMX) diagrams. The revised models have been used to obtain a closed material balance of the Rectisol Plant. This corrects the main deficiency of the initial model which had never been run to a closed material balance. For simulation purposes, the plant is divided into three sections and a rigorous ASPEN model has been developed for each of the sections: (1) H/sub 2/S Absorption and Flash Regeneration, (2) Hot Regeneration and Naphtha Extraction, and (3) Methanol Recovery and Naphtha Stripping. A single Linear ASPEN Model for the entire Rectisol Plant has also been developed for the purpose of converging the models to a closed overall material balance. Extending ASPEN by incorporating a Simultaneous Modular convergence algorithm was investigated. This worked successfully for several simple problems including that of Cavett, although there were no computer running time advantages over the conventional Sequential Modular approach. When applied to more complex problems such as the Rectisol Plant, it failed for a variety of reasons and the rigorous section models combined with amore » separate linear model approach was used instead. 13 refs., 11 figs.« less