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

Abstract

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 efficiency at 59.5%. The energy consumption increased as gasifying temperature increased and reached thermal self-sufficient condition at approximately 890 °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.