In Japan, incineration treatment has played a major role in ensuring appropriate disposal of the rapidly increasing volumes of municipal solid wastes (MSW). There is a trend for the amounts and material compositions of the MSW heading for incineration to change according to the various sorting systems put into place for waste collection. In response to this trend, we analyzed those changes noticed in the volume and material composition of waste in local municipalities that had previously introduced sorted collections, and produced statistical data on the effect of sorting on MSW for incineration. Our findings suggest that in the next ten years, the amount of MSW for incineration will decrease by around 20% while its material composition will show a decrease in combustibles. Calorific value, however, will show a more limited decrease to around 8000kJ⁄kg.

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Power generation by waste has been suggested as one possible way that municipal solid waste treatment can contribute to the development of a sound material-cycle society with a low-carbon footprint. While the total power generation capability of power generation by waste is improving each year, it currently remains at 1615 MW, as of 2008. There is an obvious need to further improve the total power generation capability and make the overall process for power generation by waste more efficient. In line with this, the concept of wide area disposal has been proposed as a means of raising the efficiency of waste-fueled power generation. However certain problems, such as region-specificity and certain hurdles in the system, still exist when considering the option of expanded waste collection areas.
While outlining the practical problems that arise with wide area disposal, this paper also introduces the ideal situation, emphasizing the viewpoint of expanded power generation by waste through wide area disposal. Moreover, as a result of turning six prefectures in the Kinki Region into a model area for the introduction and possible expansion of this technology, it was found that there are obvious cost merits to the system when it comes to the production of electricity, reduction of CO₂ emissions, and the need for refuse transportation.

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In this article, intermediate treatment of municipal solid waste (MSW) is discussed with regard to its role in the creation of a sound material cycle and low carbon society. Recent developments on incineration technology are first reviewed to reveal the potential of this technology to address the issue of global warming. The paper then evaluates some combinations of intermediate treatment methods, such as recycling of containers and packaging wastes, methane fermentation of organic wastes, and incineration under the life cycle assessment technique. The major items evaluated here are in the categories of cost, energy consumption, and carbon dioxide (CO₂) levels in the framework of MSW treatment. Some of the challenges of the co-management system, including other industrial wastes for CO₂ and energy reduction, are then also introduced. Finally, the paper also discusses the beneficial use of residue from intermediate treatment.

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Recently, in response to the need for adopting methods to reduce CO₂ emissions and prevent global warming, new, renewable energy sources for the supply of electric power have seen a rise in popularity. Waste-to-Energy is one such renewable energy source. The efficiency of power generation at MSW treatment plants in Japan has gradually seen an increase due to heightened development of power generation technologies and public support for the construction of highly efficient Waste-to-Energy plants. This paper introduces the basic framework of this trend to accelerate the expansion of new, renewable energy technologies for power generation. It also discusses ways in which Waste-to-Energy can contribute to the building of low-carbon societies from the viewpoint of power generation costs and other related issues. Overall, the paper wishes to present the high efficiency rating of the Waste-to-Energy plant to a wider audience.

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The number of WtE (Waste to Energy) plants contracted by DBO (Design Build Operation) has recently increased. In this report, we investigate the terms of the contracts regarding which party should take responsibility for risk sharing in the event of fluctuations in the condition of the waste. Using these models, we calculated how changes in the quantity and quality of the waste influence the required operation costs (i.e. business operation cost minus income from the sale of electricity).
In the investigation, for all of the DBO projects, local government is responsible for the collection of waste and the income from generation of power belongs to the private contractor. Moreover, the contractor is expected to accept the risk when changes in quantity or quality of the waste occur, providing this change is within the range of the contract. There are very few cases that can be studied which reveal any of the detailed data regarding the risks involved when changes take place in waste conditions.
On the other hand, calculations show that when the quality of waste (calorific value) increases by 10%, it has almost no bearing on operation costs. When quality of waste decreases by 10% however, operation costs tend to increase by approx. 8%. Also, when the quantity of waste decreases by 10%, operation costs increase by an estimated 7-12%. The main factor behind these aggravations is seen to be a profit decrease in the sale of electricity and an increase in the cost of auxiliary fuel.
Based on the results of this analysis and research, some suggestions for achieving sustainable business operations are presented. For DBO to realize the safe and stable operation of a WtE plant, there must be cooperation between the local government and the private contractor in order to fully recognize the magnitude of the risks involved with fluctuation in waste conditions. If this is to move forward in its goals, the two parties must work closely together to find an appropriate and fair balance in sharing this responsibility.

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This paper focuses on easing the self-regulation of nitrogen oxides (NOx) as a method for improving the efficiency of power generation in MSW incinerators. It shows about degree of impact to the surrounding environment, due to differences in NOx emission levels, the improvement of power generation and the reduction of green house gas.
With recent advances in MSW combustion technology, it is expected that the NOx concentration in exhaust emissions will reach between 100 to 120 ppm, without selective catalytic reactor (SCR). Here, we simply simulated the atmospheric diffusion of NOx at about a dozen of planned plants that were randomly selected for the experiment. Our results showed that the environmental concentration of NOx, calculated using emission that does not employ SCR, is about 1-4% higher than the environmental standards of those that do employ SCR. In addition, the amount of power generated when the self-imposed restraint value was eased from 50 to 120ppm was calculated. This appears to correspond to the carbon dioxide reduction level of 1237ton⁄year, which correlates to an expected increase of 2205MWh⁄year at the MSW incinerators using 150ton⁄day×2 furnaces scale.

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