Search

This paper presents a quantitative methodology and an empirical case study in Taiwan on modelling municipal solid waste (MSW) discards based on the consumption and MSW policy effects through a simultaneous equation system (SES) model. The results indicate that per capita consumption expenditures on 'food', 'household appliances' and 'amusement & education' are associated with the changes of the discards of most of the waste streams in Taiwan from 1992 to 2004. The developed model, meanwhile, identifies the effects of several important MSW policy measures. With regard to the model implication, consumers could try to reduce their unnecessary consumption, producers may rethink their responsibility on reducing MSW discards, and municipalities could evaluate the effectiveness of the existing policy measures to improve it upon based on the quantitative analysis. The backcasts and estimates of the discards of MSW streams could enable the planning, designing and executing of MSW system. The findings of this study would facilitate the consumer behaviour and support the policy design towards a low-waste-discard society. [ABSTRACT FROM AUTHOR]

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]

This paper presents an empirical study of how three waste management policies have affected residential waste generation and recycling behavior in Taiwan over the past decade. The three policies are unit-pricing of garbage in Taipei, a mandatory recycling program in Kaohsiung, and a nationwide policy of charging for plastic bags. We estimate policy effects on total waste, total recycling, and recycling of four specific materials, all measured by weight per capita. Unlike prior work, we find that unit-pricing and mandatory recycling policies lead to significant increases in recycling of most materials, as well as increased levels of total recycling and garbage reduction. The “plastic bag” policy is generally found to lower material-specific and total recycling rates, as well as total garbage volumes. [ABSTRACT FROM AUTHOR]

Incineration is the most important technology for treating municipal solid waste (MSW) and industrial waste in Taiwan. Currently, there are 24 large-scale MSW incineration plants operated to generate about 1.2 million metric tons of residual ash (mostly bottom ash) based on approximately 6.5 million metric tons of waste incinerated yearly. To reduce the depletion of non-renewable resources under the circular economy principle, the recycling of MSW incineration bottom ash (IBA) as recycled aggregate in concrete and construction applications has been progressed in recent years around the world. According to the official database, the trend analysis of MSW generation and treatment, electricity power and IBA generation from the MSW incineration plants over the past decade (2010–2019) was performed in this work. It showed an increased power generation, growing from 0.485 kWh/kg in 2010 to 0.530 kWh/kg in 2019. In 2019, 2738 GWh of power was sold to Taipower (one of the state-owned companies in Taiwan) for electricity grid connection, gaining income of about NT$ 5,089,383,000 (≈US$ 172,520,000) at an average rate of 1.86 NT$/kWh (0.063 US$/kWh). On the other hand, the ratios of incineration bottom ash (IBA) generation to refuse incinerated indicated a decreasing trend due to the increased operation efficiencies of MSW incineration plants. Based on the revised regulations implemented on 18 May 2020, the regulatory measures for promoting IBA recycling in Taiwan were promulgated to valorize it for the production of recycled aggregate under rigorous requirements for prevent it from polluting the environment. [ABSTRACT FROM AUTHOR]