(643f) Process Simulation and Optimization of Methanol Production Coupled to Tri-Reforming Process

Over the last decade, much attention has been given to carbon dioxide sequestration and/or conversion to useful compounds.  However, CO2 lends itself to being rather thermodynamically stable, and sequestration and conversion technologies can be quite costly.  Typical sequestration requires the separation of CO2 from fluestack gases, which is usually accomplished via amine absorption processes.  Converting the CO2, if economically sustainable, would extend our carbon resources, at least from point sources such as from steam methane reforming (SMR) and electric power generators.

            One such process for the conversion and utilization of CO₂ is tri-reforming. Tri-reforming, is relatively new approach for the treatment of CO₂ in fluestack gases and has been studied in this work. This process combines CO₂ reforming with steam reforming and methane oxidation to produce syngas (H₂ and CO) at a suitable ratio for the production of methanol, long chain alcohols, or hydrocarbons via Fischer-Tropsch synthesis. To determine the optimum operating conditions for the production of syngas with a target ratio and maximum CO₂ conversion, the effects of various factors including temperature, CH₄/Flue gas ratio, and pressure, on the compositions of syngas obtained from tri-reforming were investigated and their interactions were delicately balanced. Also, the methanol production from syngas has been rigorously simulated. Methanol was chosen as a base case due to its importance as an intermediate chemical in the chemical processing industry.  An optimum heat exchange network was obtained with the objective of minimizing utility and capital costs, respectively. General Algebraic Modeling system (GAMS) was used to perform the calculation and the results were plotted in Aspen Energy Analyzer. Furthermore, the conceptual results from heat integration were applied into the process simulation and an economic analysis was carried out to substantiate the potential profits. Results showed that the tri-reforming process, when integrated with methanol synthsis, is an economical approach for the treatment and utilization of CO₂ in flue gases.