Establishing Sustainable Society through Local Processing within Biomass Communities and Material Recycle with Carbon Dioxide and Water
Kunio Arai, Graduate School of Environmental Studies, Tohoku University, Aoba-ku Aza Aramaki Aoba-6-6-11, Sendai, Japan and Richard L. Smith, Chemical Engineering, Tohoku University, 6-6-11-413, Aoba, Aramaki, Aoba-ku, Sendai, 980-8579, Japan.
Development of independent sources for energy and for food are essential to establishing sustainable society, as presently, one may see much havoc around the world that is being caused by competition for natural resources. In the long term, material cycles must be driven by solar energy through direct and indirect conversion methods, along with material recycle methods with green chemistry that will most likely use carbon dioxide and water as the preferred working fluids. Future production systems will need to be transformed from large-scale mass production to decentralized local-scale systems that produce appropriate quantities of material from disperse solar energies. High reaction rates, simplified steps, high efficiency and high yields for production of chemicals or products on a local or appropriate level will needed to be developed. Water and carbon dioxide working fluids, especially in their supercritical state, provide the basis for decentralizing chemical processes and thus for achieving sustainable material recycle. Examples are given for replacing syntheses from petrochemicals with those from biomass feedstocks. In this lecture, also described is a 100 ha land area "Eco-Town", which shows material recycles on a practical scale. Basis of the Eco-Town is in Japan and key process is a biomass boiler for energy and agriculture area for chemical and food products. By shifting from large-scale mass production methods to decentralized local-scale methods, primary and secondary industries may be combined and these are the first steps that are needed to create sustainable communities.