Decision Support System for Effective Use of Woody and Herbaceous Biomass

Abstract

As the available biomass depends on the region, the best process structure processing the biomass also depends on the region. This suggests the importance of the decision support system which can easily be used by researchers who are not familiar with the optimization. By taking the above point into account, a support system which can derive the best biomass processing system is developed. In the proposed support system, biomass transformation processes comprising the total system, such as the harvesting, drying and chipping of biomass and various final transformation processes of biomass, are modelled in advance as individual modules. Then, as a combination of these modules, a site superstructure is generated. Site superstructures are assigned to all locations which are candidates of biomass generation area, depot, and transformation processes, and unavailable modules are removed from the site superstructure. By assigning the transportation cost among the sites, the total site superstructure can be obtained. If the generation rate of biomass and the demands depend on the season, a multi-period superstructure is generated by duplicating the total site superstructure. Finally, the optimization problem formulated as MILP is solved to derive the best system. By adopting such a hierarchical structure, the engineer can easily combine the site superstructures to make an original model which is adequate for the problem. The developed system has been applied to the design problem of a biomass processing system of the local area in a prefecture of Japan, and the effectiveness of the system was validated through case studies.