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Unit pricing is a program in solid waste management that integrates market instruments to encourage households to reduce waste generation and increase recycling. Many studies have shown that unit pricing is effective, especially when the evaluation is based on comparing outcomes before and after implementation. In this paper, we use the so-called difference-in-differences approach to evaluate unit pricing. This approach can provide a less-biased estimation, and can help to examine whether a unit pricing program generates less waste and higher recycling or results in illegal dumping in neighboring regions. Using the fee-per-bag program implemented in Taipei City, Taiwan, as a case study, we found that unit pricing does reduce the amount of garbage but its impact on recycling is not as significant as the current literature suggests. Moreover, the program causes a serious negative externality: more than 60% of the garbage reduction in the city is due to increased dumping of waste in neighboring regions. As the impact of unit-pricing on recycling is limited, policy-makers cannot rely solely on this program to enhance recycling in the management of municipal solid waste. [ABSTRACT FROM AUTHOR]

Abstract: A multiple regression analysis was used to develop two predictive models of lower heating value (LHV) for municipal solid waste (MSW), using 180 samples gathered from cities and counties in Taiwan during 2001–2002. These models are referred to as the original proposed model (OPM) and the simplified model (SM). The coefficients of multiple determinations for the OPM and SM were 0.983 and 0.975, respectively. To verify the feasibility of the models, a demonstration program based on sampling of MSW in Kaohsiung City was conducted. As a result, the OPM showed superior precision in terms of relative percentage deviation (RPD) and mean absolute percentage error (MAPE), when compared to the conventional models based on the proximate analysis, physical composition and ultimate analysis. The SM was derived by neglecting the three minor physical components used in the OPM. The resulting SM was less precise when compared to the OPM, but it was still acceptable, with a precision level better than the conventional models. It was concluded that the predictability of empirical models could be improved significantly through selection of the appropriate physical components and multiple regression analysis. [Copyright &y& Elsevier]

Incineration is a major treatment process for municipal solid waste in Taiwan. It is estimated that over 1.5Mt of incinerator ash are produced annually. This study proposes using thermal plasma technology to treat incinerator ash. Sintered glass–ceramics were produced using quenched vitrified slag with colouring agents added. The experimental results showed that the major crystalline phases developed in the sintered glass–ceramics were gehlenite and wollastonite, but many other secondary phases also appeared depending on the colouring agents added. The physical/mechanical properties, chemical resistance and toxicity characteristic leaching procedure of the coloured glass–ceramics were satisfactory. The glass–ceramic products obtained from incinerator ash treated with thermal plasma technology have great potential for building applications. [Copyright &y& Elsevier]