Process integration and economic analysis of bio-oil platform for the production of methanol and combined heat and power

Process to process material and heat integration strategies for bio-oil integrated gasification and methanol synthesis (BOIG-MeOH) systems were developed to assess their technological and economic feasibility. Distributed bio-oil generations and centralised processing enhance resource flexibility and technological feasibility. Economic performance depends on the integration of centralised BOIG-MeOH processes, investigated for cryogenic air separation unit (ASU) and water electrolyser configurations. Design and operating variables of gasification, heat recovery from gases, water and carbon dioxide removal units, water-gas shift and methanol synthesis reactors and CHP network were analysed to improve the overall efficiency and economics. The efficiency of BOIG-MeOH system using bio-oil from various feedstocks was investigated. The system efficiency primarily attributed by the moisture content of the raw material decreases from oilseed rape through miscanthus to poplar wood. Increasing capacity and recycle enhances feasibility, e.g.1350 MW BOIG-MeOH with ASU and 90% recycle configuration achieves an efficiency of 61.5% (methanol, low grade heat and electricity contributions by 89%, 7.9% and 3% respectively) based on poplar wood and the cost of production (COP) of methanol of 318.1 Euro/t for the prices of bio-oil of 75 Euro/t and electricity of 80.12 Euro/MWh, respectively. An additional transportation cost of 4.28-8.89 Euro/t based on 100 km distance between distributed and centralised plants reduces the netback of bio-oil to 40.9-36.3 Euro/t.