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Polyethylene (PE) and polypropylene (PP) can be synthesized from biomass through dehydration, dimerization, and metathesis reactions from ethanol or methanol-to-olefin reaction of synthesis gas. This paper examines the socioeconomic aspects of such biomass-derived resin production, which are composed of environmental impacts quantified by life cycle analysis (LCA) and the structure of generated value flows specified by structural path analysis (SPA) based on a Japanese input–output table. Missing inventory data were estimated by process simulation using Aspen Plus™ and Aspen HYSYS™ with design information extracted from the literature, patents, and design heuristics. LCA based on actual and demonstration plants with process simulation shows the environmental advantage of biomass-derived resins on greenhouse gas (GHG) emissions reduction. PE production has the largest effect on GHG emissions reduction, followed by bioethanol from a gasoline mixture, and PP. The uncertainties in agricultural processes also influence the potential application of international and domestic bioethanol production and synthesis gas obtained from the gasification of waste woods. According to SPA results for gasoline, PE, PP, and plastic products, the cyclicality of resins and plastic products, which was quantitatively analyzed as the total cyclic cash flows from target products to final demands, is much larger than that of gasoline. Based on these results, biomass-derived resin production has the potential to increase added values in an economy, with a corresponding decrease in GHG emissions. [ABSTRACT FROM AUTHOR]

To elucidate the macro-structure of the PM2.5 emissions generated by Japan''s economic activities, this paper presents an emission inventory of primary particles of PM2.5 with high sectoral resolution based on the Japanese Input–Output Tables, comprising some 400 sectors. These primary PM2.5 emissions were estimated by multiplying the estimated energy consumption associated with each fuel type by a PM10 emission factor incorporating the technological level of dust collection in each sector and the mass ratio of PM2.5 to PM10. Non-energy emissions from agricultural open burning were also determined. Total PM2.5 emissions in 2000 were 252 kt, 49% of which were due to mobile emission sources. Changes in total PM2.5 emissions between 1990 and 2000 were also calculated. This showed that a substantial increase in energy sector emissions due to rising coal consumption was offset by a sharp decline in emissions from road vehicles and shipping vessels, resulting in an overall decrease in total emissions. In addition, the emissions induced by economic demand in each sector were quantified by means of input–output analysis, which revealed that demand for construction, foods and communications and services constituted the principal causes of real domestic emissions. An assessment of sectoral contributions to PM2.5 emissions that takes into account the effects of human exposure, expressed as external costs, suggests that the contribution of transportation is greater than indicated on the grounds of direct emissions alone. [Copyright &y& Elsevier]