A wide range of activities focusing on the utilization of recycled resources is being promoted as a means of moving toward the development of a Sound Material-Cycle Society. Although such activities target just a small percentage of the multitude of products being manufactured, many companies are currently endeavoring to promote the recycling of resources on a larger scale.
This study introduces how one company went about developing a waste reduction program based on the environmental accounts of the company’s CSR reports.
When looking at the various types of industries, companies that supply electricity or gas had considerably higher Resource Recycling Costs. This study highlights the ‘Ratio of Resource Recycling Cost (RRC-Ratio)’ in the sales of the companies. The research shows that the resource recycling wholesale industry is the highest with regard to the RRC-Ratio. Furthermore, the RRC-Ratio proves to be higher in the construction industry, which directs a considerable amount of money toward the costs of resource recycling.
This research introduces the new ‘Solid Waste Management Index (SWM-Index)’ as an indicator for evaluating how well a company manages to carry out its responsibilities to reduce industrial waste.

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The production of bioethanol from non-standard potatoes and waste syrup by enzyme treatment and subsequent fermentation. By diluting potato mash with waste syrup, its viscosity was decreased and its sugar content was increased. The mixture of potato and syrup was liquefied (at 85 °C for 30min) and saccharified (at 60 °C for 2hrs) using enzymes, and the glucose was completely recovered. The glucose recovery efficiency was kept at 90%, even when the quantity of enzymes used for liquefaction and saccharification were reduced to 2/5 and 3/5, respectively. In batch fermentation, 68.8g/L of ethanol concentration and 90% of the fermentation yield were obtained from the mixture of potato mash and syrup. Then, non-sterilized continuous ethanol fermentation was carried out using a one-stage fermentor, and an ethanol concentration of 64.0g/L, which corresponded to an ethanol production yield of 90%, and an ethanol productivity of 25.6g/L/h were achieved. Calculating from these experimental results, 988kL of bioethanol and about 400 tons of dried distiller's grains with solubles (DDGS) could be produced from 1,614 tons of non-standard potatoes and 10,000 tons of waste syrup.

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In this paper, we evaluate the effects that consumption patterns have on CO₂ emissions and waste generated from electrical and electronic equipment in China. We focus on consumer decisions regarding product selection, usage and disposal assuming that these behaviors significantly influence energy efficiency and the flow of discarded products. Four distinguishing consumption patterns were revealed as a result of a questionnaire and from research literature : “Business as Usual”, “Frequent Replace”, “Chain of Uses” and “Quality and Wisdom.” We also evaluate differences in product flow and environmental impacts from 2006 to 2030. Results show that “Quality and Wisdom” is the best style of consumption with regard to both CO₂ emissions and reduction of waste generation. When the effects on living standards are taken into consideration, however, a combination of “Quality and Wisdom” and “Chain of Users” seems to best contribute to an optimization of trade-offs between multiple targets of resource consumption, the release of hazardous materials and economic disparities.

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In this study, a new hydrogen fermentation system with separation and condensation by ion exchange was proposed for the reduction of environmental loads and the reuse of hydrogen fermentation wastewater. The characteristics of the ion exchange for the wastewater were clarified. Hydrogen fermentation experiments were carried out on the assumption that the metabolites separated from the wastewater using ion exchange were reused as dilution water in this system.
Major metabolites, which were acetate, butyrate and lactate, were separated and condensed by the ion exchange of hydrogen fermentation wastewater. A weak ion exchange resin WA10, which has a low specific surface area, had high performance for organic acid removal because the physical adsorption of nutrient sources in the wastewater suppressed inhibitors. The wastewater with organic acids removed by ion exchange is suggested as a possibility for reuse as dilution water and as a pH adjuster in hydrogen fermentation tanks.

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Kyoto City was taken as an example of a domestic urban area in order to estimate the actual amount of food and paper biomass found in municipal solid waste. The annual amounts of food and paper waste were measured at 222 kt-wet and 223 kt-wet, respectively. At present, most of this is processed through incineration. After evaluation of the greenhouse gas (GHG) reduction effect and energy recovery ratio of the utilization system for this biomass, a biogasification (high-temperature and dry-type methane fermentation) system with gas engine (GE) power generation was found to be more beneficial than the existing system, which uses direct combustion with steam power generation and direct combustion with composting. In addition, biogasification with hydrolysis is expected to give a 27% improvement in GHG reduction effect and energy recovery ratio over the present system of combined biogasification with hyperthermal
(80 °C) hydrolysis technology operated by exhaust heat from a GE power plant. Futhermore, the use of biogas in fuel cells can reduce GHG emissions by up to 1.7 times compared to GE use. Diffusion of energy conversion technology with high efficiency is therefore being recommended for the reduction of GHG in Japan.

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A kinetic study on the volatilization of PbO from CaO-SiO₂-Al₂O₃ molten slag, which simulated the volatilization of PbO in municipal solid waste melting, was conducted at a temperature range of 1673 to 1773 K in an 80% N₂, 20% O₂ atmosphere with a space velocity of N₂-O₂ mixed gas of 1.50×10⁻⁴~3.01×10⁻³ m·s⁻¹ in the melting furnace. The composition of the employed slag was varied by changing the weight ratio of CaO, SiO₂ and Al₂O₃ from 10 to 60wt%. The rate of volatilization of PbO was determined based on the film theory, with the assumption that the kinetic model might be applicable to the transportation of PbO from CaO-SiO₂-Al₂O₃ molten slag to the gas phase. The rate of volatilization of PbO from CaO-SiO₂-Al₂O₃ molten slag in an N₂-O₂ atmosphere was estimated by taking into consideration the rate of vaporization of Mn from iron melting in an argon gas flow condition at atmospheric pressure. In the present study, the overall mass transfer coefficient was determined as a function of slag composition and temperature, and the rate of volatilization of PbO from CaO-SiO₂-Al₂O₃ molten slag was estimated.
As a result, it was apparent that the rate of volatilization of PbO from CaO-SiO₂-Al₂O₃ molten slag in the N₂-O₂ gas flow condition was influenced by both the rate of vaporization of PbO from the interface of gas-molten slag and the mass transfer rate of PbO in the liquid phase, when the flow rate of 80% N₂, 20% O₂ mixed gas was higher than 9.02×10⁻⁴ m·s⁻¹. The calculated results on the volatilization of PbO predicted by the present kinetic study were in fairly good agreement with the experimental results for a low viscous CaO-SiO₂-Al₂O₃ molten slag with 0.40 to 1.4Pa·s viscosity under the present experimental conditions.

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The Containers and Packaging Recycling Law in Japan requires municipalities to deliver post-consumer PET bottles to a body designated by the law (the institutional route). In recent years, however, the number of municipalities that provide PET bottles to independent recyclers and recycling brokers is on the rise (the independent disposal route). We conducted a questionnaire on prices and conditions in the independent disposal route of post-consumer PET bottles. The average price (yen/kg) had declined from 15.2 in 1997 to -21.3 in 2001 and risen steadily to 36.2 in 2008. When considering characteristics of target municipalities, the price was relatively higher in municipalities that regarded the economic aspect as more important. On the other hand, the price was relatively lower in municipalities that took account of other aspects, such as the shortage of their own compression bailing facilities. The latter municipalities will be likely to continue to provide PET bottles via the independent disposal route even if the price via the institutional route becomes higher than the independent disposal route.

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