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[Display omitted] • New tool, Circular Flow, tackles the lack of consistency in measuring circularity. • Circular Flow provides quantitative results for energy and material flows. • Circular Flow can be applied in any sector/system with material and/or energy flows. • Novel visual representation helps to spot opportunities for internalizing value. • A case study in a Brazilian agroindustrial cooperative was performed. Unlike the linear model "take-make-use-dispose", the circular economy model "grow-make-use-restore" intends to potentiate material and energy flows within a system with the premise of increasing environmental gains. Moreover, circular economy practices can be alternatives for closing loops in companies from different sectors, with material-, waste-, and energy-related initiatives towards promoting greater internal value-adding. However, the lack of consistent tools for measuring circularity of processes and companies is a gap yet to be covered. To tackle this gap, this paper's aims are: (i) to build a new tool, called Circular Flow, for generating greater internal value and competitive advantage in organizations and identify potential circular economy-related opportunities for closing loops based on external flows, (ii) to apply the tool in a case study, an organization that presents material and energy (electricity) flows and exchanges with other organizations, and (iii) to discuss the integration and potential opportunities for the tool in organizations. The novel, Circular Flow, tool is based on a set of circular graph visualizations, and quantitative circularity indicators. For the graphical visualization, the software tool R (using the Circlize package) was used. The graphs aid the visualization of several interconnected pieces of information, allowing to show all quantitative flows of inputs and outputs, intuitively showing the paths (origin and destination of each flow) within the boundaries of the system under study. The quantitative indicators, e.g. Circularity of the organization (Circ p) and Circularity of each process (Circ o), show a circularity index ranging from 0% to 100%, which can be assessed at different levels. The criteria to select these indicators are based on quantities of inputs and outputs regarding mass and electricity. The tool has been applied in a case study of a rural property in southern Brazil, which region holds a tradition for milk and pig farming. The use of the tool showed the involvement of the rural property with its neighbors and with an agroindustrial cooperative. Keeping these flows within the system may increase environmental gains by reducing transportation, using renewable sources of energy, reducing costs, and boosting the generation of jobs and income in the region due to new market opportunities and business models. [ABSTRACT FROM AUTHOR]

• Identify the relationship between causes and practices of waste prevention in supermarkets and suppliers. • Consumers demand high aesthetic standards from fruit and vegetables. • Inventory reallocation and minimum amount displayed of F&V reduce waste. • Supermarkets in this study prefer to discard food as there are no legal penalties. • Self-interest of retailers is reinforced through a limited and reactive coordination. This study aims to identify the main causes of food waste (especially fruit and vegetables) and their relationship with prevention practices at supermarket and supplier levels. To do so, we conducted case studies in four Brazilian supermarket chains and their suppliers. Our findings show that although supermarkets seem to be concerned about avoiding food waste, they mostly focus on internal prevention actions, reflecting the lack of collaboration and information between supermarkets and suppliers. The low investment of supermarkets in actions to prevent food waste is focused only on their internal operations and, despite this, training is inefficient due to the high level of staff turnover and lack of involvement of suppliers in participating in this training. The use of technologies such as packaging, traceability, refrigeration, and transport equipment is insufficient, it increases production costs. A lack of strict legislation in Brazil makes it difficult for supermarkets and suppliers to donate food. Cultural issues specific to Brazil, such as consumer overhandling fruit and vegetables before buying these products, generate a great deal of waste. The paper contributes to the literature by identifying the main root causes of food waste and providing a list of prevention practices that supermarkets and suppliers can benefit from. Managerially, it can help supermarket managers spot the causes of food waste within their operations, and hence change, improve or implement practices and behavior to prevent food waste. [ABSTRACT FROM AUTHOR]

• Waste management face lack of recyclable market, system coverage and access to marketable waste. • New methodological strategy to calculate sustainability indicators. • Proposal of hierarchized actions according to temporal urgency of implementation. • Design of actions have high applicability in low- and middle-income countries. • Practical options for solutions with respective necessary investment are presented. Brazilian municipalities face several difficulties while carrying out the municipal selective waste collection (MSWC); at the same time, waste pickers organizations (WPOs) need to overcome many challenges to compete in the waste management market. In order to reach the requirements of the Brazilian National Solid Waste Policy (NSWP), it is necessary to know which factors interfere in the performance of MSWC programs and WPOs to understand the relationships between these factors. The objective of this paper was to evaluate the sustainability of MSWC programs and WPOs in the State of Espírito Santo, Brazil, and propose a new methodological strategy. For data collection, questionnaires were given to municipal civil workers from 24 municipalities and managers of 23 WPOs to calculate sustainability indicators and their correlations. Means and frequencies were calculated to analyze indicators in relation to sustainability; peer-to-peer correlation analyses were performed to the construct graphs that obtained correlation coefficients, which were applied to study the normality distribution. For each indicator, we provided necessary investments to practical solutions. As a result, a methodological proposal was presented to improve their actions, which was hierarchized by degrees of temporal urgency for their implementation. The design of the actions has great potential to improve and develop sustainability practices in WPOs and MSWC programs. Due to the low quality of primary data collected, we recommend the creation of the data control systems to continuously monitor. [ABSTRACT FROM AUTHOR]

• Statistical models of LHV based on Brazilian wastes physical characteristics. • Empirical measures of moisture and heating value from samples of MSW in Brazil. • Samples were collected based on statistically representative sampling methodology. • Two models for accurate prediction of experimental data for LHV was built. Municipal solid waste (MSW) management is a serious problem for public administrations, especially in terms of treatment and final disposal. These wastes have a high energy content and one of the possibilities of treatment is the recovery of energy through thermochemical processes. The parameter used to measure the amount of useful energy available in collected waste when submitted to thermochemical processes is called the lower heating value (LHV), which is usually determined in the laboratory or through empirical models from the literature. To this end, this paper aims to present two models for prediction of the LHV in the municipal solid waste of the municipality of Santo André. Samples were collected from 36 garbage trucks in the above-mentioned city, from September 2015 to January 2016. The models were developed based on the results of the gravimetric composition and laboratory analysis. The technique used to develop the models was the multiple linear regression by least squares method. As a result, the models obtained mean absolute percentage error (MAPE) indexes of 5.09% and 5.52%, considered excellent according to the literature classification. In addition, the calculated LHV of the Santo André municipal waste was 7.03 MJ/kg, which indicates a great potential for energy recovery using thermochemical processes. These are the first LHV prediction models developed in Brazil, which has been a significant accomplishment in Brazil. The proposed models were developed using empirical measurements of moisture in the solid waste and the LHV on samples collected with a statistically representative sampling method. [ABSTRACT FROM AUTHOR]

Although recycling is a viable alternative to minimizing the impacts of the Municipal Solid Waste (MSW), identification of the local recycling market is a requirement for its empowerment. This paper aims to assess the recyclable solid waste market in 16 cities of Brazil. Through the application of interviews, field research and secondary data collection this research observed that while relying on poor infrastructure and on Government subsidies, the 12 pickers organizations surveyed can deliver 18.53% of recyclable waste to recycling with an average sorting productivity of 109 kg/picker/day and average earnings of US$ 293.40/picker/month. Based on the validated methods, 17% of these organizations were classified as having average efficiency, whereas 82% of them operated with very low efficiency. The investment required for the adequacy and expansion of the sorting capacity of waste pickers’ organizations has been estimated at US$ 2.5 M, which could be counterbalanced by the savings with the current US$ 2 M/year spent with the disposal of recyclable waste into landfills. We also estimate new 189 job openings in the pickers’ organizations to meet the requirements of the proposed scenario, contrasting with the current 93 cooperative members currently formalized. Regarding the consumer market, only few recycling companies were identified in the region, which may justify the low price paid for waste. The market for recyclables is mostly composed of micro and small companies that generally carry out the collection, transportation, sorting, and commercialization. [ABSTRACT FROM AUTHOR]

Brazil has an increasing rate of e-waste generation, but there are currently few adequate management systems in operation, with the largest share of Waste Electrical and Electronic Equipment (WEEE) going to landfill sites or entering informal chains. The National Solid Waste Policy (2010) enforces the implementation of reverse logistics systems under the shared responsibility of consumers, companies and governments. The objective of this paper is to assess sustainability and prioritise system alternatives for potential implementation in the metropolitan region of Rio de Janeiro. Sustainability criteria and decision alternatives were defined by elicitation of stakeholders. The adopted multicriteria approach combines Life Cycle Assessment with qualitative evaluations by a small sample of regional experts with knowledge of the problem. The recommended system consists of a hybrid WEEE collection scheme with delivery points at shops, metro stations and neighbourhood centres; a pre-treatment phase with the involvement of private companies, cooperatives and social enterprises; and full recycling of all components in the country. [ABSTRACT FROM AUTHOR]

Abstract: Settlement evaluation in sanitary landfills is a complex process, due to the waste heterogeneity, time-varying properties and influencing factors and mechanisms, such as mechanical compression due to load application and creep, and physical–chemical and biological processes caused by the wastes decomposition. Many empirical models for the analysis of long-term settlement in landfills are reported in the literature. This paper presents the results of a settlement monitoring program carried out during 6years in Belo Horizonte experimental landfill. Different sets of field data were used to calibrate three long-term settlement prediction models (rheological, hyperbolic and composite). The parameters obtained in the calibration were used to predict the settlements and to compare with actual field data. During the monitoring period of 6years, significant vertical strains were observed (of up to 31%) in relation to the initial height of the experimental landfill. The results for the long-term settlement prediction obtained by the hyperbolic and rheological models significantly underestimate the settlements, regardless the period of data used in the calibration. The best fits were obtained with the composite model, except when 1year field data were used in the calibration. The results of the composite model indicate settlements stabilization at larger times and with larger final settlements when compared to the hyperbolic and rheological models. [Copyright &y& Elsevier]

Abstract: Recycling and the related issue of sustainable development are increasing in importance around the world. In Brazil, the new National Policy on Solid Wastes has prompted discussion on the future of electronic waste (e-waste). Over the last 10years, different e-waste collection systems and recycling processes have been applied globally. This paper presents the systems used in different countries and compares the world situation to the current Brazilian reality. To establish a recycling process, it is necessary to organize efficient collection management. The main difficulty associated with the implementation of e-waste recycling processes in Brazil is the collection system, as its efficiency depends not only on the education and cooperation of the people but also on cooperation among industrial waste generators, distributors and the government. Over half a million waste pickers have been reported in Brazil and they are responsible for the success of metal scrap collection in the country. The country also has close to 2400 companies and cooperatives involved in recycling and scrap trading. On the other hand, the collection and recycling of e-waste is still incipient because e-wastes are not seen as valuable in the informal sector. The Brazilian challenge is therefore to organize a system of e-waste management including the informal sector without neglecting environmentally sound management principles. [Copyright &y& Elsevier]

Abstract: Although the concern with sustainable development and environment protection has considerably grown in the last years it is noted that the majority of decision making models and tools are still either excessively tied to economic aspects or geared to the production process. Moreover, existing models focus on the priority steps of solid waste management, beyond waste energy recovery and disposal. So, in order to help the lack of models and tools aiming at the waste treatment and final disposal, a new concept is proposed: the Cleaner Treatment, which is based on the Cleaner Production principles. This paper focuses on the development and validation of the Cleaner Treatment Index (CTI), to assess environmental performance of waste treatment technologies based on the Cleaner Treatment concept. The index is formed by aggregation (summation or product) of several indicators that consists in operational parameters. The weights of the indicator were established by Delphi Method and Brazilian Environmental Laws. In addition, sensitivity analyses were carried out comparing both aggregation methods. Finally, index validation was carried out by applying the CTI to 10 waste-to-energy plants data. From sensitivity analysis and validation results it is possible to infer that summation model is the most suitable aggregation method. For summation method, CTI results were superior to 0.5 (in a scale from 0 to 1) for most facilities evaluated. So, this study demonstrates that CTI is a simple and robust tool to assess and compare the environmental performance of different treatment plants being an excellent quantitative tool to support Cleaner Treatment implementation. [Copyright &y& Elsevier]

Abstract: This paper presents an attempt to model the water balance in the metropolitan center landfill (MCL) in Salvador, Brazil. Aspects such as the municipal solid waste (MSW) initial water content, mass loss due to decomposition, MSW liquid expelling due to compression and those related to weather conditions, such as the amount of rainfall and evaporation are considered. Superficial flow and infiltration were modeled considering the waste and the hydraulic characteristics (permeability and soil–water retention curves) of the cover layer and simplified uni-dimensional empirical models. In order to validate the modeling procedure, data from one cell at the landfill were used. Monthly waste entry, volume of collected leachate and leachate level inside the cell were monitored. Water balance equations and the compressibility of the MSW were used to calculate the amount of leachate stored in the cell and the corresponding leachate level. Measured and calculated values of the leachate level inside the cell were similar and the model was able to capture the main trends of the water balance behavior during the cell operational period. [Copyright &y& Elsevier]

Abstract: Sales of electrical and electronic equipment are increasing dramatically in developing countries. Usually, there are no reliable data about quantities of the waste generated. A new law for solid waste management was enacted in Brazil in 2010, and the infrastructure to treat this waste must be planned, considering the volumes of the different types of electrical and electronic equipment generated. This paper reviews the literature regarding estimation of waste electrical and electronic equipment (WEEE), focusing on developing countries, particularly in Latin America. It briefly describes the current WEEE system in Brazil and presents an updated estimate of generation of WEEE. Considering the limited available data in Brazil, a model for WEEE generation estimation is proposed in which different methods are used for mature and non-mature market products. The results showed that the most important variable is the equipment lifetime, which requires a thorough understanding of consumer behavior to estimate. Since Brazil is a rapidly expanding market, the “boom” in waste generation is still to come. In the near future, better data will provide more reliable estimation of waste generation and a clearer interpretation of the lifetime variable throughout the years. [Copyright &y& Elsevier]

Abstract: Shear strength characterization of MSW materials is a mandatory task when performing analyses related to landfill design and landfill geometry improvements. Despite the considerable amount of research focusing on MSW mechanical behavior there remain certain aspects which are not completely understood and deserve attention in particular the case of the undrained behavior of MSW. This paper presents the results of a comprehensive laboratory testing program using a large-scale triaxial apparatus at the Federal University of Bahia, Salvador, Brazil. The effect of factors such as confining pressure, unit weight, fiber content, rate of loading and over-consolidation on the MSW mechanical response were investigated. Tested samples presented typical MSW shear/strain curves (concave upward) in all the tests, despite the pore water pressure reaching levels almost equal to the confining pressure. The obtained results show that increasing confining stress, unit weight, loading rate, fiber content and over-consolidation lead to an increase in the MSW shear strength. The importance of the fibrous components in the waste behavior is highlighted and graphs showing the variation of the MSW shear strength with fiber content in different drainage conditions are shown. The authors believe these results could be of interest to many companies, especially considering the new trend of plastic material recycling (prior landfilling) for energy recovery purposes. [Copyright &y& Elsevier]

Abstract: The characteristics of municipal solid waste (MSW) play a key role in many aspects of waste disposal facilities and landfills. Because most of a landfill is made up of MSW, the overall stability of the landfill slopes are governed by the strength parameters and physical properties of the MSW. These parameters are also important in interactions involving the waste body and the landfill structures: cover liner, leachate and gas collection systems. On the other hand, the composition of the waste, which affects the geotechnical behavior of the MSW, is dependent on a variety of factors such as climate, disposal technology, the culture and habits of the local community. It is therefore essential that the design and stability evaluations of landfills in each region be performed based on the local conditions and the geotechnical characteristic of the MSW. The Bandeirantes Landfill, BL, in São Paulo and the Metropolitan Center Landfill, MCL, in Salvador, are among the biggest landfills in Brazil. These two disposal facilities have been used for the development of research involving waste mechanics in recent years. Considerable work has been made in the laboratory and in the field to evaluate parameters such as water and organic contents, composition, permeability, and shear strength. This paper shows and analyzes the results of tests performed on these two landfills. The authors believe that these results could be a good reference for certain aspects and geotechnical properties of MSW materials in countries with similar conditions. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an overview of cell phone recycling programs currently available in the United States. At the same time, it also provides analyses of the current recycling situation and possible recycling alternatives for Brazil. Although there are several recycling options in the United States, collection rates are still only 10% of all potential devices because customers are not aware of these possibilities. The whole system is financially based on reselling refurbished cell phones and recycled materials to developing countries which represent an effective and strong market. Several recyclers offer funds to collection partners who are either charities or who work with charities while obtaining the materials that they need in order to run their operations. A mobile phone recycling system for Brazil considering the United States experience and the Extended Producer Responsibility (EPR) principle is suggested. A deposit/refund/advance-recycling fee is proposed which might be implemented as a voluntary industrial initiative managed by PRO Brazil, a producer responsibility organization. One widespread public–private agreement will integrate all mobile phone stakeholders, and environmental education actions and promotional events will promote citizen’s participation. [ABSTRACT FROM AUTHOR]

The present paper aims to make the energy saving potential provided by waste recycling in Brazil evident by pointing out more specifically the benefits regarding climate change mitigation. In this case, based on the energy saved due to the recycling process of an exogenous amount of waste, we have built two scenarios in order to show the potential for indirectly avoiding CO2 emissions in the country as a result of the recycling process. According to the scenario, 1 Mt and 3.5 Mt of CO2, respectively, would be avoided per year due to solid waste recycling. The international context for greenhouse gas emissions reduction, such as the United Nations Framework Convention on Climate Change and its Kyoto Protocol has been taken into account. [Copyright &y& Elsevier]