Municipal solid waste management instruments that influence the use of the refuse as fuel in developing countries: A critical review.

Landfills are the destination of most of the refuse generated whereas composting, material recycling, and Waste-to-Energy (WtE) technologies are not commonly employed in developing countries. However, the destination for energy purposes could be supplied with this refuse, improving the viability of energy use. Thus, this article raises some questions to identify aspects that could encourage its use as refuse-derived fuel (RDF) in these countries. Among them, does environmental education affect the municipal solid waste (MSW) source separation with emphasis on a destination? Can selective collection and extended producer responsibility (EPR) affect the MSW for energy recovery? Is there competition between the recycling market and the energy market for RDF? A systematic review of the literature was conducted to gather data and provide answers to such questions. This enabled to observe that EPR, selective collect expansion and source separation influence the quantity and quality of waste sent for energy use. Both internal and external factors impact on source separation. Additionally, there is evidence to support that despite several studies showing their technical, economic, environmental and social viability, the methods of energy usage of the refuse still need to improve their deployment in developing countries. In addition to identifying the main research gaps to be filled in future studies, the article also identified the instruments of MSW management that are to be applied in developing countries to divert recyclable and organic waste from landfill.

Characterization of Mixed Pellets Made from Rubberwood (Hevea brasiliensis) and Refuse-Derived Fuel (RDF) Waste as Pellet Fuel.

The objective of this study was to investigate the production and properties of mixed pellets made from rubberwood (Hevea brasiliensis Muell. Arg) and refuse-derived fuel (RDF) waste with no added binder. Three different conditions of mixed pellets were developed to compare their chemical and physical properties to rubberwood pellets. The produced samples were subjected to both ultimate and proximate analyses. The contents of C, H, N, S, and Cl significantly increased with the increasing amount of refuse-derived fuel in the samples, resulting in reduction of the volatile matter. The mechanical durability of the pellet samples ranged between an average value of 98 and 99%. Mixed pellets containing 50% of rubberwood and 50% of refuse-derived fuel have improved heating values by 22.21% compared to rubberwood pellets. Moreover, mixed pellets having 50% of wood and 50% of refuse-derived fuel had the highest density and the highest energy compared to the other samples. Based on the findings of this study, it appears that the manufactured mixed pellets have the potential to be used as high-energy fuel.

Rotas tecnológicas, desafios e potencial para valoração energética de resíduo sólido urbano por coprocessamento no Brasil / Technological routes, challenges and potential for municipal solid waste energetic valorization by coprocessing in Brazil

RESUMO Mais de dez anos depois da implantação da Política Nacional de Resíduos Sólidos, por meio da Lei federal n° 12.305/2010, a elaboração e a execução de políticas públicas com resultados positivos na gestão dos resíduos sólidos urbanos são precárias. O coprocessamento desses produtos em fornos de clínquer pode ser uma alternativa viável para melhorar esse cenário, mas encontra diversas dificuldades de ordem técnica e econômica. Neste trabalho, estimou-se a composição e a gravimetria dos resíduos no Brasil com base em dados secundários, de forma a estimar o poder calorífico inferior resultante de diferentes formas de pré-tratamento desses produtos: triagem de orgânicos, triagem de orgânicos e inertes, secagem para redução da umidade e combinação das três estratégias. Com base nos valores obtidos de poder calorífico, estima-se a capacidade de coprocessamento de resíduos pré-tratados pelas indústrias nacionais que possuem licenciamento ambiental para essa atividade. O tratamento prévio dos resíduos resultou em aumentos entre 20 e 56% em relação ao cenário-base. Observou-se que, para o cenário sem triagem, mas com secagem térmica do resíduo, até 8% dos resíduos com destinação inadequada no Brasil atualmente podem ser recebidos por indústrias de cimento para o coprocessamento, desde que haja viabilidade técnica para sua substituição e transporte.

ABSTRACT More than ten years after the implementation of the Solid Waste Nacional Policy by Brazilian Federal Law nº 12.305/2010, elaboration and execution of public policies with positive results in Municipal Solid Waste management is precarious. Coprocessing of Municipal Solid Waste in cement kilns can be a viable alternative for improving this scenario, but still encounters many technical and economical challenges. In this study, an estimate of the mean gravimetric composition of Municipal Solid Waste in Brazil is presented, based on secondary data, so as to estimate the resultant lower heating value resultant of different Municipal Solid Waste pre-treatment alternatives; separation of the organic fraction, separation of organic and inert fraction, drying of Municipal Solid Waste and all strategies combined. Based on the obtained lower heating value, an estimate of the yearly potential of Municipal Solid Waste coprocessing in industries already licensed for coprocessing of waste in Brazil is presented. Pre-treatment of Municipal Solid Waste resulted in lower heating value improvements ranging from 20 to 56% when compared to the base scenario. It is observed that, in the scenario where the Municipal Solid Waste is dried but not triaged, up to 8% of the Municipal Solid Waste that is currently disposed inappropriately in Brazil could be received by cement industries for coprocessing, as long as there is technical feasibility for the substitution and transportation.

Synergizing environmental, social, and economic sustainability factors for refuse derived fuel use in cement industry: A case study in Espirito Santo, Brazil.

The cement industry has been under pressure due to the environmental impact of high cement production, which demands a significant amount of energy and results in greenhouse gas (GHG) emissions. In many developed countries, the cement industry has sought to replace conventional fossil fuels with alternatives to minimize GHG emissions; however, Brazil has underexploited this possibility. Considering the potential of refuse-derived fuel (RDF) to reduce the non-recycled waste disposed in landfills, and its suitable performance as an alternative fuel for cleaner cement production, this paper presents a reverse logistics network analysis for RDF production planning with respect to local economic incentives, social euqity and justice, pollution prevention, and global environmental concerns regarding carbon emissions reduction. The reverse logistics network involves important stakeholders related in waste management in Espirito Santo, Brazil, especially harmonizing social sustainability concerns between waste pickers' cooperatives and waste retailers. By considering the waste generated in 78 municipalities in the Espírito Santo state, the possible levels of fuel replacement in cement industries reflects the economic sustainability of the timeframe of the solid waste management policy implementation. The results showed that the RDF to be produced varies from 42,446.5 tonnes in 2024 with a small fuel replacement by cement industries, to 567,092.1 tonnes in 2040 if all non-recyclable waste available can be used to produce RDF. The avoided annual disposal costs via this network analysis vary from $3,855,412.0 in the initial years to $47,822,876.8 in the year 2040 under optimistic conditions, representing around 25% of the total cost in the network. The cost and GHG emitted reduced significantly in all simulated scenarios; however, the financial incentives are essential for achieving the network social sustainability.