Sustainability analysis of the bio-dimethyl ether (bio-DME) production via integrated biomass gasification and direct DME Synthesis Process

The sustainability analysis based on life cycle assessment (LCA) of bio-dimethyl ether (bio-DME) production via an integrated biomass gasification and direct DME synthesis (IBG-DME) process, using oil palm residue as feedstock, was performed. The IBG-DME process was simulated in Aspen plus. Operating at selected condition, the IBG-DME was an exothermic process, whereas for 1 kg h-1 of oil palm trunk, bio-DME of 0.3456 kg h-1 and bio-methanol of 0.015 kg h-1 were produced as main product and by product, respectively, with energy effi-ciency at 59.5%. The energy consumption increased as gasifying temperature increased and reached thermal self-sufficient condition at approximately 890 degrees C but the CO2 emission showed opposite trend. LCA result indicated that the carbon footprint of each unit operation relied on the energy consumption. For biomass gasification section, the global warming potential (GWP) accounted for approximately 91% of the total impact. The DME production section highly contributed toward the ozone depletion potential (ODP), eco-toxicity (ET), and human toxicity-non-carcinogenics (HTNC) whereas the syngas cleaning and conditioning section highly contributed toward GWP, human toxicity potential by ingestion (HTPI), and aquatic toxicity potential (ATP). The endpoint impact on the ecosystem were higher than the human health for all process sections.

Automated summary

A sustainability analysis of bio-dimethyl ether (bio-DME) production via an integrated biomass gasification and direct DME synthesis (IBG-DME) process using oil palm residue as feedstock was conducted. The energy efficiency of the IBG-DME process was found to be 59.5%, with bio-DME and bio-methanol as the main and by-product, respectively. The carbon footprint and environmental impact were highly dependent on the energy consumption and the different process sections.