CO2 Utilization Process Simulation for Enhancing Production of Dimethyl Ether (DME)

Increase in the world energy demand also increases the concentration of CO2 in the atmosphere, which contributes to global warming and ocean acidification. This study proposed the simulation process to utilize CO2 released from the acid gas removal unit in one of gas processing plants in Indonesia to enhance the production of dimethyl ether (DME) through unreacted gas recycle that can be beneficial in reducing CO2 emission to the atmosphere. Simulation was developed in Unisim R390.1 using Peng-Robinson-Stryjek-Vera (PRSV) as a fluid package. Simulation was validated by several studies conducted by many researchers and giving satisfactory results especially in terms of productivity, conversion, and selectivity as a function of reactor temperatures in the indirect and the direct DME synthesis processes. Simulation results show that the DME production was enhanced by around 49.6% and 65.1% for indirect and direct processes, respectively, at a recycling rate of 7 MMSCFD. Compressor is required to increase the unreacted gas pressure to the desired pressure in the methanol reactor or dual methanol-DME reactor in both processes. Specific power consumption (SPC) was used as a tested parameter for the effectiveness of recycling unreacted gas. Based on the simulation, the direct DME synthesis process is superior over the indirect process in terms of DME and methanol productions, SPCs, and system energy efficiencies.