(331c) Superstructure-Based Optimization of Carbon Dioxide Conversion and Utilization Via Syngas Intermediate
In this work, we postulate a superstructure consisting of multiple layers to form process intermediates and products. To achieve a desired conversion, each layer is comprised of necessary reaction, separation and product upgradation steps along with heating and compression steps which produce auxiliary emissions. The first layer of the superstructure consists of seven process alternatives (dry reforming, partial oxidation, steam methane reforming, auto-thermal reforming and their hybrid combinations) for syngas formation starting from flue gas, natural gas and biogas. The second layer forms intermediates (e.g., methanol, dimethyl ether, heavy olefins) which can further be processed to produce hydrogen-based fuels and chemicals in subsequent layers. The overall superstructure is then used to identify an optimal CO2 conversion and utilization route in GAMS environment with two separate objectives â maximization of net CO2 utilization and minimization of total annualized cost. Specifically, we obtain a maximum net CO2 utilization of 57% for feedstock conversion to syngas with consideration of the auxiliary emissions. The presentation would also cover further conversion of syngas to subsequent value-added products.
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