(372j) Life Cycle Analysis of the Syngas-to-Aromatics Processes
Direct conversion of syngas to aromatics (STA) represented one of the shortest routes bridging the coal- or natural gas-based industry (to provide syngas) between the oil- based industry (the dominant route to product aromatics in current stage). It is, for the first time, reported the life cycle analysis (LCA) of this process via the building of a systematic model using Aspen Plus V8.4 by our group. Direct STA process and the indirect STA (syngas firstly to produce methanol, then methanol was converted into aromatics) was compared in the conversion range of CO from 50% to 80%, including the evaluation of energy consumption and economic aspects. Low conversion of CO resulted in the high partial pressure of recycled syngas, low partial pressure of aromatics and the associated increased difficulty in separation and the associated increased investment and operational cost, which were analyzed quantitatively. The economic cost of currently attained in the indirect STA are equal to the direct STA with conversion of CO at 66-72%. Above these values, direct STA would have obvious advantages in saving operational cost and the construction costs. This present simulation provid the insight on the upper limits of the process in developing catalysts and the technology.