Exergy and Energy Analysis of Effective Utilization of Carbon Dioxide in the Gas-to-Methanol Process

Abstract

Two process models are used to convert carbon dioxide into methanol. These processes have been extended and improved using Aspen Plus simulator software. Both processes are found in the CO₂ correction system. In this machine, the desired synthesis gas is produced in a flexible configuration. At the same time, the conversion of CO₂ to hydrogen via a copper-based catalyst has been accomplished in the methanol blending and bonding machine to produce the target product, methanol. The simulation results show that, in both proposed CO₂-gas-to-methanol process, the energy efficiency can be significantly increased, and the CO₂ emission significantly reduced as compared to the conventional Gas-to-methanol process. Energy efficiency is also affected by the recycling factor. The higher the recycling factor, the better the CO₂ conversion and reaction will be as well as increased energy efficiency and decreased CO₂ emission. However, the refractive index seems to have little effect on energy efficiency, and the useful recovery that goes back to the breeder is meager. Implementation of the carbon dioxide utilization process for gas-to-methanol units has significant impacts on these systems in the term of energy and exergy, the performance ratios increased 6.5 and 4.2%, respectively, compared to the base cases. Regarding exergoeconomics, the exergy cost rate decreased 71 $/s. An exergoenvironmental analysis showed the impacts are significant. The environmental impact difference increased by 3%, which, because of its definite form, means a carbon dioxide utilization plant makes a more significant positive difference in the environment.