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Concept: Waste hierarchy


This work presents the enforcement performance of recent Haulien County, Taiwan municipal solid waste (MSW) recycling management programs. These programs include: Mandatory Refuse Sorting and Recycling, Diverse Bulk Waste Reuse, Pay-as-you-Discharge, Total Food Waste Recycling, Restricted Use on Plastic Shopping Bags & Plastic Tableware, Recycling Fund Management, and Ash Reuse. These programs provide incentives to reduce the MSW quantity growth rate. It was found that the recycled material fraction of MSW generated in 2001 was from 6.8%, but was 32.4% in 2010 and will increase stably by 2-5% yearly in the near future. Survey data for the last few years show that only 2.68% (based on total MSW generated) of food waste was collected in 2001. However, food waste was up to 9.7 % in 2010 after the Total Food Waste Recycling program was implemented. The reutilization rate of bottom ash was 20% in 2005 and up to 65% in 2010 owing to Ash Reuse Program enforcement. A quantified index, the Total Recycle Index, was proposed to evaluate MSW management program performance. The demonstrated county will move toward a zero waste society in 2015 if the Total Recycle Index approaches 1.00. Exact management with available programs can lead to slow-growing waste volume and recovery of all MSW.

Concepts: Waste management, Reuse, Recycling, Incineration, Waste, Waste picker, Waste hierarchy, Waste management concepts


The objective of this study is to discuss the role of networks formed of waste-picker cooperatives in ameliorating problems of final disposal of solid waste in the city of Rio de Janeiro, since the city’s main landfill will soon have to close because of exhausted capacity. However, it is estimated that in the city of Rio de Janeiro there are around five thousand waste-pickers working in poor conditions, with lack of physical infrastructure and training, but contributing significantly by diverting solid waste from landfills. According to the Sustainable Development Indicators (IBGE, 2010a,b) in Brazil, recycling rates hover between 45% and 55%. In the municipality of Rio de Janeiro, only 1% of the waste produced is collected selectively by the government (COMLURB, 2010), demonstrating that recycling is mainly performed by waste-pickers. Furthermore, since the recycling market is an oligopsony that requires economies of scale to negotiate directly with industries, the idea of working in networks of cooperatives meets the demands for joint marketing of recyclable materials. Thus, this work presents a method for creating and structuring a network of recycling cooperatives, with prior training for working in networks, so that the expected synergies and joint efforts can lead to concrete results. We intend to demonstrate that it is first essential to strengthen the waste-pickers' cooperatives in terms of infrastructure, governance and training so that solid waste management can be environmentally, socially and economically sustainable in the city of Rio de Janeiro.

Concepts: Waste management, Sustainability, Recycling, Incineration, Waste, Landfill, Waste picker, Waste hierarchy


Waste reduction and recycling at the city level will acquire greater significance in the near future due to rising global volumes of waste. This paper seeks to identify policy-relevant drivers for successful promotion of waste reduction and recycling. Factors influencing the success of waste reduction and recycling campaigns are identified. Two case study cities in Japan which depict the successful use of the 3Rs (reduce, reuse and recycle) at the municipal level are presented. In these cases, the existence of incinerators, which are generally considered as disincentives for recycling, was not functioning as a disincentive but rather as an incentive for waste reduction. Owing to the high cost of incineration facilities, the movement to close incinerators has become a strong incentive for waste reduction and recycling in these two cities. The study suggests that careful consideration is necessary when making decisions concerning high-cost waste treatment facilities with high installation, maintenance and renewal outlays. In addition, intensive source separation and other municipal recycling initiatives have a high potential for producing positive results.

Concepts: City, Japan, Waste management, Reuse, Recycling, Incineration, Waste hierarchy, Waste treatment technology


Most research on perovskite solar cells has focused on improving power-conversion efficiency and stability. However, if one could refurbish perovskite solar cells, their stability might not be a critical issue. From the perspective of cost effectiveness, if failed, perovskite solar cells could be collected and recycled; reuse of their gold electrodes and transparent conducting glasses could reduce the price per watt of perovskite photovoltaic modules. Herein, we present a simple and effective method for removing the perovskite layer and reusing the mesoporous TiO2-coated transparent conducting glass substrate via selective dissolution. We find that the perovskite layer can be easily decomposed in polar aprotic solvents because of the reaction between polar aprotic solvents and Pb(2+) cations. After 10 cycles of recycling, a mesoporous TiO2-coated transparent conducting glass substrate-based perovskite solar cell still shows a constant power-conversion efficiency, thereby demonstrating the possibility of recycling perovskite solar cells.

Concepts: Solvent, Solar cell, Photovoltaics, Reuse, Recycling, Photovoltaic module, Photovoltaic array, Waste hierarchy


Current European waste policy does not mainly aim to treat waste streams but rather place in the foreground of interest the complete supply chain of a product. Waste prevention and re-use do have the highest priority and they take effect before the end-of-life phase of a product or a material is reached. Recycling only takes the third place whereas recovery and disposal represent the least favourable options. Recycling can help to decrease the consumption of primary resources but it does not tackle the causes but only the symptoms. In principle, recycling processes require energy and will generate side streams (i.e. waste). Furthermore, there are insuperable barriers and the practice is far from 100% recycling. The philosophy of waste prevention and re-use is completely different since they really tackle the causes. It is self-evident that a decrease of waste will also decrease the consumption of resources, energy and money to process the waste. However, even if European legislation is proceeding in the right direction, a clear decrease in waste generation did not occur up to now. Unfortunately, waste generation represents a positive factor of economic growth. Basically, waste generation is a huge business and numerous stakeholders are not interested to reduce waste. More sophisticated incentives are required to decouple economic growth from waste generation.

Concepts: European Union, Economics, Waste management, Recycling, Waste, Waste hierarchy, Waste management concepts, Third place


The opportunity to recycle microalgal culture medium for further cultivation is often hampered by salinity increases from evaporation and fouling by dissolved and particulate matter. In this study, the impact of culture re-use after electro-flocculation of seawater-based medium on growth and biomass productivity of the halotolerant green algal strain Tetraselmis sp., MUR 233, was investigated in pilot-scale open raceway ponds over 5months. Despite a salinity increase from 5.5% to 12% (w/v) NaCl, Tetraselmis MUR 233 grown on naturally DOC-enriched recycled medium produced 48-160% more ash free dry weight (AFDW) biomass daily per unit pond area than when grown on non-recycled medium. A peak productivity of 37.5±3.1gAFDWm(-2)d(-1) was reached in the recycled medium upon transition from ∼14% to ∼7% NaCl. The combination of high biomass-yielding mixotrophic growth under high salinity has been proven to be a successful sustainable cultivation strategy.

Concepts: Lake, Mass, Waste management, Sustainability, Reuse, Recycling, Waste hierarchy, Remanufacturing


Material recycling often leads to environmental benefits when compared to thermal treatments or landfilling and is therefore positioned in the waste hierarchy as the third priority after waste prevention and reuse. To assess the environmental impacts of recycling and the related substitution of primary material, linear steady-state models of physical flows are typically used. In reality, the environmental burdens of collection and recycling are likely to be a non-linear function of the collection rate. This short communication aims at raising awareness of the non-linear effects in separate collection systems and presents the first non-linear quantitative model for PET bottle recycling. The influence of collection rates on the material quality and the transport network is analyzed based on the data collected from industrial partners. The results highlight that in the present Swiss recycling system a very high collection rate close to 100% yields optimum environmental benefits with respect to global warming. The empirical data, however, provided indications for a decrease in the marginal environmental benefit of recycling. This can be seen as an indication that tipping points may exist for other recycling systems, in which the environmental benefits from substituting primary materials are less pronounced than they are for PET.

Concepts: Present, Scientific method, Waste management, Quantitative research, Reuse, Recycling, Waste hierarchy, Waste minimisation


Solid waste management in many cities of developing countries is not environmentally sustainable. People traditionally dispose of their solid waste in unsuitable urban areas like sidewalks and satellite dumpsites. This situation nowadays has become a serious public health problem in big Latin American conurbations. Among these densely-populated urban spaces, the Colombia’s capital and main city stands out as a special case. In this study, we aim to identify the factors that shape the attitudes towards source-separated recycling among households in Bogotá. Using data from the Colombian Department of Statistics and Bogotá’s multi-purpose survey, we estimated a multivariate Probit model. In general, our results show that the higher the household’s socioeconomic class, the greater its effort for separating solid wastes. Likewise, our findings also allowed us to characterize household profiles regarding solid waste separation and considering each socioeconomic class. Among these profiles, we found that at lower socioeconomic classes, the attitudes towards solid waste separation are influenced by the use of Internet, the membership to an environmentalist organization, the level of education of the head of household and the homeownership. Hence, increasing the education levels within the poorest segment of the population, promoting affordable housing policies and facilitating Internet access for the vulnerable population could reinforce households' attitudes towards a greater source-separated recycling effort.

Concepts: City, Waste management, Sustainability, Recycling, Waste-to-energy, Waste, Waste collection, Waste hierarchy


The main aim of this study was to perform a Life Cycle Assessment (LCA) study as well as an economic evaluation of the recovery of recyclable materials in a municipal solid waste management system. If citizens separate erroneously waste fractions, they produce both environmental and economic damages. The environmental and economic evaluation was performed for the case study of Nola (34.349 inhabitants) in Southern Italy, with a kerbside system that assured a source-separation of 62% in 2014. The economic analysis provided a quantification of the economic benefits obtainable for the population in function of the achievable percentage of source-separation. The comparison among the environmental performance of four considered scenarios showed that the higher the level of source-separation was, the lower the overall impacts were. This occurred because, even if the impacts of the waste collection and transport increased, they were overcome by the avoided impacts of the recycling processes. Increasing the source-separation by one percent could avoid the emission of 5 kg CO2 eq. and 5 g PM10 for each single citizen. The economic and environmental indicators defined in this study provide simple and effective information useful for a wide-ranging audience in a behavioural change program perspective.

Concepts: Waste management, Sustainability, Recycling, Waste-to-energy, Waste, Life cycle assessment, Waste collection, Waste hierarchy


The increasing amount of food waste generated as a direct consequence of its excessive production, mismanagement and wasteful behaviours, represents a real challenge in promoting resource efficiency. In the UK, the lack of robust mass flow data hinders both the ability to understand and address food waste challenges, and to devise long-term sustainable prevention strategies. In recognition of these challenges, this paper seeks to: i) provide insights into the UK’s annual estimates of food mass flows, including imports, exports, distribution, consumption, surplus food production, and final disposal, and ii) scrutinise the uptake and surplus food redistribution as a potential food waste prevention strategy. Evidence collected from several enterprises and community-led initiatives in the UK, and London specifically, supports that there is an increasing potential of making a shift towards food redistribution and reuse. Further analysis has shown that the outreach of food redistribution initiatives in the UK is currently limited, possibly because redistribution efforts remain largely fragmented and independent from each other. It is concluded that a national commitment could be instrumental in encouraging the roll-out of this practice, and governmental support through fiscal incentives, could lead to the development of a larger and coherent surplus food redistribution system, ultimately enabling food waste prevention and recovery of food’s multi-dimensional value. Implications Our manuscript entitled ‘FOOD FLOWS IN THE UK: THE POTENTIAL OF SURPLUS FOOD REDISTRIBUTION TO REDUCE WASTE’ deals with the topical issue of the increasing amount of food waste generated as a direct consequence of excessive production, mismanagement, and wasteful behaviour, representing a real challenge in achieving sustainability and resource efficiency. Currently only a small fraction of food is redistributed back in to the system. Yet, a considerable fraction of food waste generated is edible, thus better planning, storage and coordination amongst the different stakeholders in the food supply chain is required in order to prevent its wastage and promote its reuse in accordance with the waste hierarchy.

Concepts: European Union, Food, United Kingdom, Waste management, Recycling, International trade, Waste, Waste hierarchy