Solid waste management in Macao: practices and challenges

The rapid economic development and population growth in Macao have resulted in a large increase in refuse generated over the past decade. In 2003, the quantity of solid waste generated reached 249,255 tons, corresponding to 1.52 kg/day per capita. This figure has been gradually increasing. Domestic solid waste is the primary source of solid waste generation. The data showed that a considerable amount of the solid waste generated can be recycled and reutilized. Due to Macao's small geographic area and high cost of land, landfilling has the lowest priority for waste disposal. Solid waste incineration has been given a top priority over other waste disposal methods although it is much more expensive. In the last decade, more than 80% of the total waste in Macao was incinerated. However, the incineration capacity of the Macao Incineration Plant is going to reach its saturation earlier than expected. Waste minimization, the establishment of an effective waste collection and disposal fee system, and alternate ways dealing with the limited capacity of waste treatment facilities are regarded to be major challenges in the future.     

深圳市环境污染与经济增长关系的实证研究

采用深圳市1996—2009年的统计数据,分析了环境污染与经济增长之间的关系及其影响因素。结果表明,可吸入颗粒物浓度、工业废水排放量、工业废气排放量和工业固体废弃物产生量与人均GDP的拟合曲线呈现典型环境库兹涅茨曲线(EKC)特征,至2007年,这4个环境指标已经全部跨越拐点,目前处于EKC的右侧。同时,运用灰色关联法分析经济发展、社会发展、环境管理的变化趋势,探讨了深圳EKC的演变主要是由GDP增长、环保投资、职工年平均工资和技术进步等因子驱动的。     

Setting priorities for waste management strategies in developing countries.

This study aimed to determine whether the waste management systems, that are presently applied in affluent countries are appropriate solutions for waste management in less developed regions. For this purpose, three cities (Vienna, Damascus and Dhaka) which differ greatly in their gross domestic product and waste management were compared. The criteria for evaluation were economic parameters, and indicators as to whether the goals of waste management (protection of human health and the environment, the conservation of resources) were reached. Based on case studies, it was found that for regions spending 1-10 Euro capita(-1) year(-1) for waste management, the 'waste hierarchy' of prevention, recycling and disposal is not an appropriate strategy. In such regions, the improvement of disposal systems (complete collection, upgrading to sanitary landfilling) is the most cost-effective method to reach the objectives of solid waste management. Concepts that are widely applied in developed countries such as incineration and mechanical waste treatment are not suitable methods to reach waste management goals in countries where people cannot spend more than 10 Euro per person for the collection, treatment and disposal of their waste. It is recommended that each region first determines its economic capacity for waste management and then designs its waste management system according to this capacity and the goals of waste management.     

Municipal solid waste management in China: a comparative analysis

This paper illustrates an overview of the past and present MSWM strategies in China. A comparison is made with MSWM in China, and other developed and developing countries to identify and analyze the problems of existing MSWM, and evaluate some effective suggestion to overcome the limitations. Rapid urbanization and economic growth are the main factors of increasing MSW generation in China. The generating MSW has 55.86 % food waste with high moisture contain due to unavailable source separation. Chinese MSWM is dominated by 60.16 % landfilling, whereas incineration, untreated discharge, and other treatments are 29.84, 8.21, and 1.79 %, respectively. In 2014, a total of 604 sanitary landfills, 188 incineration plants, and 26 other units were used for MSWM. With the magnitude of timing, the increasing rate of incineration unit and disposal capacity is higher than the landfill. In 2004–2014, the disposal capacity of landfill and incineration is increased from 68.89 to 107.44 and 4.49 to 53.3 million tons, respectively. However, the heating value in the majority of Chinese incineration plants is 3000–6700 kJ/kg and the inappropriate leachate treatment can be found in 47 % landfill sites. A proper taxation system for MSW disposal is not fully implemented in China, which has a negative impact on overall MSW recycling. From the comparative study of MSWM, it is revealed that the source separation MSW collection, high energy recovery from incineration plants, appropriate leachate treatment, effective landfill location and management, increase waste recycling and proper taxation system for MSW disposal are essential to improve MSWM in China.     

Korea's policy instruments for waste minimization

This paper considers the current status of waste generation and waste treatment trends, and introduces a wide variety of policy instruments for waste minimization at every stage of economic activity in Korea, i.e., production, distribution, and consumption. At each stage, the Korean government has imposed a policy mix of direct regulations and economic incentives. These policy instruments have made definite contributions to a reduction of waste generation and an increase in the recycling rate. Despite these fruitful outcomes, there are still some shortcomings with respect to efficiency and equity. Among other aspects, this paper examines three representative economic incentives – the charge system, the volume-based-collection fee system, and the deposit–refund system – and identifies shortcomings in each. Some suggestions are made for the creation of better systems of economic incentives. However, many experts insist that this kind of piecemeal change in each policy instrument is not enough to achieve the ultimate goal of resource circulation and an environmentally friendly society, especially in Korea, which is a country with little land, a high population density, and a high economic growth rate. Among experts, special emphasis is placed on the activation of recycling industries to achieve these goals. Received: April 2, 2001 / Accepted: September 10, 2001     

The estimation of N2O emissions from municipal solid waste incineration facilities: The Korea case

The greenhouse gases (GHGs) generated in municipal solid waste (MSW) incineration are carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O). In South Korea case, the total of GHGs from the waste incineration facilities has been increasing at an annual rate 10%. In these view, waste incineration facilities should consider to reduce GHG emissions.This study is designed to estimate the N₂O emission factors from MSW incineration plants, and calculate the N₂O emissions based on these factors. The three MSW incinerators examined in this study were either stoker or both stoker and rotary kiln facilities. The N₂O concentrations from the MSW incinerators were measured using gas chromatography-electron capture detection (GC-ECD) equipment.The average of the N₂O emission factors for the M01 plant, M02 plant, and M03 plant are 71, 75, and 153 g-N₂O/ton-waste, respectively. These results showed a significant difference from the default values of the intergovernmental panel on climate change (IPCC), while approaching those values derived in Japan and Germany. Furthermore, comparing the results of this study to the Korea Energy Economics Institute (KEEI) (2007) data on waste incineration, N₂O emissions from MSW incineration comprised 19% of the total N₂O emissions.     

Economic growth and selection of municipal waste treatment options in Bangkok

A reasonable selection of waste treatment options is indispensable to address challenges in waste management. Introduction of incineration plants for municipal waste in Bangkok had been considered in the past, but each time it was dismissed. In 2013, however, the Bangkok Metropolitan Administration (BMA) decided to introduce an incinerator facility with electricity generation. This study examined how changes in socio-economic factors resulting from economic growth affected the BMA’s decision. First, we conducted interviews of key relevant stakeholders (policymakers and other experts) to determine what kinds of changes in socio-economic factors affected their decision. Then, for interpretation and confirmation of the results from interview, we quantitatively estimated changes in environmental factors (e.g., greenhouse gas emissions), financial factors (e.g., construction and operating costs), and social factors (e.g., employment) in 1990, 2000, and 2012. Based on the result of interview and quantitative analysis, we illustrated the complicated structure of the mechanism of how economic growth affected the selection of waste treatment options in Bangkok, particularly those that led to the selection of the incineration. In addition to local conditions, global economic also affected the waste treatment policy in Bangkok even though waste management is usually thought of as a local issue.     

Research for MSW flow analysis in developing nations

Developing nations have various problems regarding municipal solid waste (MSW). Therefore, to carry out a systematic review of the MSW problems in the target area and to formulate a well-considered management plan, it is extremely important to understand the present MSW flow in the region. One of the authors participated in the nine solid waste management (SWM) studies in developing nations undertaken under the technical cooperation program of the Japan International Cooperation Agency (JICA). Based on these studies, this paper reviews the results of research in developing countries regarding different MSW streams, the factors that cause the differences, and the elements considered to have the most impact on those streams. This research identifies several issues regarding MSW streams in developing nations. The MSW generation rate per capita in developing countries is generally said to grow in proportion to the GNP. However, the findings of this research show no correlation between the two; instead, there is a relationship between the GNP and the collection rate. To formulate proper future MSW management plans in countries with low collection rates, it is very important to forecast the rates of self-disposed and recycled waste, and their fluctuations. These are affected by urban structure, collection services, etc. Received: January 27, 2000 / Accepted: July 19, 2000     

Characteristics of MSW and heat energy recovery between residential and commercial areas in Seoul

This paper analyzes the amount and characteristics of municipal solid waste (MSW) according to the inhabitant density of population and the business concentration in 25 districts in Seoul. Further, the heat energy recovery and avoided CO₂ emissions of four incineration plants located in residential and commercial areas in Seoul are examined. The amount of residential waste per capita tended to increase as the density of inhabitants decreased. The amount of commercial waste per capita tended to increase as the business concentration increased. The examination of the heat energy recovery characteristics indicated that the four incineration plants produced heat energy that depended on residential or commercial areas based on population and business. The most important result regarding avoided CO₂ emissions was that commercial areas with many office-type businesses had the most effective CO₂ emission savings by combusting 1 kg of waste. Assuming the full-scale operation of the four incineration plants, the amount of saved CO₂ emissions per year was 444 Gg CO₂ and 57,006 households in Seoul can be provided with heat energy equivalent to 542,711 Nm³ of LNG.     

Treatment and disposal alternatives for health-care waste in developing countries--a case study in Istanbul, Turkey.

Efficient health-care waste management is crucial for the prevention of the exposure of health-care workers, patients, and the community to infections, toxic wastes and injuries as well as the protection of the environment (Safe Management of Wastes from Health-care Activities. World Health Organization, Geneva). The amount of health-care waste produced in the Istanbul Metropolitan City in Turkey is 30 ton day(-1) in total. The method used for the final disposal of most of the health-care waste of Istanbul is incineration. However, a great portion of the infectious waste is disposed of with the domestic waste into the sanitary landfill because of improper segregation practices applied in the health-care institutions. Therefore the alternatives for the treatment and disposal of health-care waste were evaluated. The technical information related to the available treatment technologies including incineration, microwave irradiation, mobile or stationary sterilization, etc. were also investigated. The capital investment cost, transportation/operational costs for each alternative method and the different locations for installation were compared. When the data collected were evaluated, it was found that separate handling and disposal of health-care waste generated on the European and the Asian sides of the city was the most economic and practicable solution. As a result, it was concluded that the capacity of the Kemerburgaz-Odayeri incineration plant is enough to incinerate the health-care waste generated on the European side of Istanbul, the construction of a new incineration plant or a stationary sterilization unit for the disposal of health-care waste generated on the Asian side was the most effective alternative.     

Predicted growth of world urban food waste and methane production.

Landfill gas emissions are one of the largest anthropogenic sources of methane especially because of food waste (FW). To prevent these emissions growing with world population, future FW best management practices need to be evaluated. The objective of this paper was therefore to predict FW production for 2025 if present management practices are maintained, and then, to compare the impact of scenario 1: encouraging people to stay in rural areas and composting 75% of their FW, and; of scenario 2, where in addition to scenario 1, composting or anaerobically digesting 75% of urban FW (UFW). A relationship was established between per capita gross domestic product (GDP) and the population percentage living in urban areas (%UP), as well as production of municipal solid waste (MSW) and UFW. With estimated GDP and population growth per country, %UP and production of MSW and UFW could be predicted for 2025. A relatively accurate (R(2) > 0.85) correlation was found between GDP and %UP, and between GDP and mass of MSW and FW produced. On a global scale, MSW and UFW productions were predicted to increase by 51 and 44%, respectively, from 2005 to 2025. During the same period, and because of its expected economic development, Asia was predicted to experience the largest increase in UFW production, of 278 to 416 Gkg. If present MSW management trends are maintained, landfilled UFW was predicted to increase world CH4 emissions from 34 to 48 Gkg and the landfill share of global anthropogenic emissions from 8 to 10%. In comparison with maintaining present FW management practices, scenario 1 can lower UFW production by 30% and maintain the landfill share of the global anthropogenic emissions at 8%. With scenario 2, the landfill share of global anthropogenic emissions could be further reduced from 8 to 6% and leachate production could be reduced by 40%.     

Sustainable solid waste management: An integrated approach for Asian countries

Solid waste management (SWM) has been an integral part of every human society. The approaches for SWM should be compatible with the nature of a given society, and, in this regard, Asian countries are no exception. In keeping with global trends, the systems are being oriented to concentrate on sustainability issues; mainly through the incorporation of 3R (reduce, reuse and recycle) technologies. However, degree and nature of improvements toward sustainability are varying and depend on the economic status of a country. High-income countries like Japan and South Korea can afford to spend more to incorporate 3R technologies. Most of the latest efforts focus on “Zero Waste” and/or “Zero Landfilling” which is certainly expensive for weaker economies such as those of India or Indonesia. There is a need to pragmatically assess the expectations of SWM systems in Asian countries. Hence, in this paper, we analyze the situation in different Asian countries, and explore future trends. We conceptually evaluate issues surrounding the sustainability of SWM. We propose a multi-pronged integrated approach for improvement that achieves sustainable SWM in the context of national policy and legal frameworks, institutional arrangement, appropriate technology, operational and financial management, and public awareness and participation. In keeping with this approach, a generic action plan has been proposed that could be tailored to suit a situation in a particular country. Our proposed concept and action plan framework would be useful across a variety of country-specific scenarios.     

日本生活垃圾焚烧灰渣的资源化利用

日本生活垃圾的焚烧率高达80%,对焚烧灰渣的处理也比较先进,其资源化利用方式主要有在熔融设施进行熔融处理后制成熔融灰渣、作为水泥原料及路基材料等。介绍了日本生活垃圾焚烧灰渣的产生及资源化利用情况,以期对我国处理焚烧灰渣有所借鉴。     

Application of system dynamics modeling for evaluation of different recycling scenarios in Singapore

The influence of socioeconomic factors, such as population and rapid economic growth, and the change of consumption and living patterns make waste management in Singapore, a complex issue. Due to limited land and resources, the solid waste management scheme requires a comprehensive approach. Therefore, system dynamics (SD) modeling was applied to assess alternative strategies for solid waste management by interconnecting landfill capacity and recycling efficiency with reference to the projection on waste generation. Nine different scenarios were investigated to identify the best approach to maintain environmental sustainability without inhibiting the economic growth. Four subsystems (i.e., population, economy, waste recycling, and waste disposal) have been incorporated into the SD model to broaden the effectiveness of the waste management system. Research findings revealed that a high economic pattern and a high recycling rate are recommended to satisfy the requirements for economic growth and environmental sustainability while extending landfill capacity for waste disposal. Even though the balance of expenditure could be increased by the high recycling rate, it meets the need for long-term incineration and landfill planning.     

The contemporary Asian silver cycle: 1-year stocks and flows

The stocks and flows of silver throughout the Asian economy for 1997 have been quantified, with major flows examined over their entire life cycle, including mining, production, fabrication, and manufacture, product use, and waste management. By compiling the findings of 11 country-level material flow analyses, a regional analysis was created. The reliability and availability of the data varied, with the most confidence given to the earlier life stages and the most uncertainty existing later. Overall, Asia is a net importer of silver, requiring nearly 7000 Mg of silver in 1997. Approximately 2200 Mg Ag are mined, and production waste totals about 640 Mg Ag. The flow of silver into use equals 9900 Mg Ag, with a considerable build-up of 7100 Mg Ag entering in-use stock. Silver waste sent directly to the environment, in addition to landfilled waste, totals 1600 Mg Ag. Much variation exists when examining country-level silver flows on a per capita basis. India and Thailand’s fondness for silver jewelry greatly increases their silver flows into use and in-use stock. Japan’s high overall consumption reflects its high GDP per capita. Regionally, a significant potential exists to tap the silver contained in the in-use stocks and to enhance the recycling rates.     

Regulatory structures and operational environment in the Portuguese waste sector

This research computes the influence of the operational environment on the efficiency of the Portuguese urban solid waste services. A sample of 29 solid waste utilities encompassing the whole continental country was used for this purpose. Particularly, we apply the non-parametric double bootstrap model to estimate the effect of various explanatory factors on robust data envelopment analysis estimates. In general, we find a significant influence of the environmental context on the solid waste utilities’ performance. The environmental context is characterized by gross domestic product per capita, distance to treatment facilities, population density, regulation, type of management, composting and incineration services.     

Environmental impact assessment of the incineration of municipal solid waste with auxiliary coal in China

The environmental impacts of waste incineration with auxiliary coal were investigated using the life-cycle-based software, EASEWASTE, based on the municipal solid waste (MSW) management system in Shuozhou City. In the current system, MSW is collected, transported, and incinerated with 250kg of coal per ton of waste. Based on observed environmental impacts of incineration, fossil CO(2) and heavy metals were primary contributors to global warming and ecotoxicity in soil, respectively. Compared with incinerators using excess coal, incineration with adequate coal presents significant benefits in mitigating global warming, whereas incineration with a mass of coal can avoid more impacts to acidification, photochemical ozone and nutrient enrichment because of increased electricity substitution and reduced emission from coal power plants. The "Emission standard of air pollutants for thermal power plants (GB13223-2011)" implemented in 2012 introduced stricter policies on controlling SO(2) and NO(x) emissions from coal power plants. Thus, increased use of auxiliary coal during incineration yields fewer avoided impacts on acidification and nutrient enrichment. When two-thirds of ash is source-separated and landfilled, the incineration of rest-waste presents better results on global warming, acidification, nutrient enrichment, and even ecotoxicity in soil. This process is considered a promising solution for MSW management in Shuozhou City. Weighted normalized environmental impacts were assessed based on Chinese political reduction targets. Results indicate that heavy metal and acidic gas emissions should be given more attention in waste incineration. This study provides scientific support for the management of MSW systems dominated by incineration with auxiliary coal in China.     

Material cycles in Asia: especially the recycling loop between Japan and China

In this article, we clarify the current status of Japanese exports and Chinese imports of secondary resources. A total of around 10 million metric tons (t) of secondary resources are exported annually from Japan to China, Hong Kong, and Korea. Hong Kong plays the role of a transshipment point, especially regarding the trade in plastic waste, and China imports much from the USA and Japan, often through Hong Kong. The secondary resources exported from Japan include both byproducts from manufacturing processes and end-of-life products or materials. The great demand in China, and the difference in prices between countries, drive this transboundary shipment, although Japan has enacted various recycling laws that were implicitly intended to promote domestic recycling. In China, the imported secondary resources are recycled, usually by means of primitive and low-cost hand labor. The greatest concern is whether there are still improper (illegal or polluting) recycling activities in China. International material cycles should prevent environmental pollution and ensure efficient resource utilization. To that end, the following measures are needed: cooperative control of the trade of secondary resources between countries, the alignment of domestic laws with the regulations in other countries based on the actual trade activities, and the realization of sound practices for global resources management.     

Municipal solid waste management in Malaysia: Practices and challenges

Rapid economic development and population growth, inadequate infrastructure and expertise, and land scarcity make the management of municipal solid waste become one of Malaysia’s most critical environmental issues. The study is aimed at evaluating the generation, characteristics, and management of solid waste in Malaysia based on published information. In general, the per capita generation rate is about 0.5–0.8 kg/person/day in which domestic waste is the primary source. Currently, solid waste is managed by the Ministry of Housing and Local Government, with the participation of the private sector. A new institutional and legislation framework has been structured with the objectives to establish a holistic, integrated, and cost-effective solid waste management system, with an emphasis on environmental protection and public health. Therefore, the hierarchy of solid waste management has given the highest priority to source reduction through 3R, intermediate treatment and final disposal.     

Evaluation method of automobile recycling systems for Asia considering international material cycles: application to Japan and Thailand

To examine an appropriate recycling system for end-of-life vehicles (ELVs) from Japan in the context of Asia, an Asian international automobile recycling input-output (AI-ARIO) analysis is presented. The AI-ARIO analysis spatially expands the existing ARIO analysis within the framework of the waste input-output (WIO) analysis developed by Nakamura et al., which considers the interdependence between the flow of goods and wastes in a country. This analysis focuses on the local and global cycles for ELVs in Asia and can evaluate the environmental and economic effects of alternative recycling systems. We estimated the AI-ARIO table for Japan and Thailand and applied it to scenario analyses covering the restriction of ELV trade between the two countries, the introduction of new recycling techniques in Thailand, and centralized treatment in Japan. We verified the applicability and effectiveness of the AI-ARIO analysis through the scenario analyses.