Thermo-economic optimisation of the polygeneration of synthetic natural gas (SNG), power and heat from lignocellulosic biomass by gasification and methanationElectronic supplementary information (ESI) available: Database of the generated results in Matlab/Octave-language. See DOI: 10.1039/c1ee02867g

• Main Authors: Gassner, Martin, Marchal, Franois
• Format: Journal Article
• Language: English
• Published: 25.01.2012
• ISSN: 1754-5692; 1754-5706
• DOI: 10.1039/c1ee02867g

After a brief review of the current research on the production of synthetic natural gas (SNG) from lignocellulosic biomass by gasification and methanation, this paper presents detailed thermo-economic process optimisation of the polygeneration of SNG, power and heat. Based on a previously developed model, all suitable candidate configurations of a superstructure of promising technologies for the individual conversion steps are optimised with respect to the overall efficiency and investement cost with an evolutionary, multi-objective algorithm. In an extensive analysis, the influence of process technology, operating conditions and process integration on the thermo-economic performance is discussed and the best technology matches are determined. Systematically optimised flowsheets might thereby convert 66 to 75% of the dry wood's lower heating value to SNG while cogenerating a considerable amount of power and/or industrial heat. In order to provide a general database of optimal plant configurations, cost exponents that quantify the economies of scale are regressed, and the most profitable flowsheets are identified for different energy price scenarios and scale. A comparison with current literature on SNG production from biomass reveals the potential of applying such systematic process systems engineering approaches for the design of energy- and cost-efficient biofuel plants. Based on an extensive superstructure, 60 process configurations are optimised and compared with respect to performance, which reveals the potential of applying systematic process systems engineering approaches for the design of energy- and cost-efficient biofuel plants.