An assessment of the illegal dumping of construction and demolition waste

2_(Des)construir_Economia_Circular). This work was also supported by the Portuguese Fundação para a Ciência e a Tecnologia (FCT) under the project LA/P/0069/2020 granted to the Associate Laboratory ARNET.Addressing the illegal dumping of construction and demolition waste (CDW) is challenging because there are significant costs associated with clean-up actions but, for many local authorities, no data is available to describe this reality and to support the decision-making process. This research is focused on how to study the dynamic of CDW dumpsites, characterising these occurrences in order to understand the factors that influence them and to raise awareness to the problem with the results obtained. It involved the municipalities of a rural region, with scant infrastructure for CDW treatment, in monthly observations of the aforementioned sites. In total, 136 dumpsites were observed, with 65% of them located on public-owned land. For these dumpsites, 18 thousand tonnes of CDW were estimated, of which 59% correspond to the mineral fraction. The cost of removing the abandoned CDW was estimated at between €84 and €99 per tonne, with the component directly associated with municipal resources estimated at around 28% of the total. During the one-year monitoring period, 26 new dumpsites were observed, and 156 tonnes per month of CDW were recorded. Performance indicators demonstrated that the municipalities with some type of local solution for CDW management report less illegal dumping. These findings are relevant for filling the gaps in data about the illegal dumping of CDW on local scales and in less developed countries, supporting decision-making processes. In terms of research, the results address gaps in the literature since there is scarce data about these occurrences.publishersversionpublishe

Strategies to promote construction and demolition waste management in the context of local dynamics

2_(Des)construir_Economia_Circular). This work was also supported by the Portuguese Fundação para a Ciência e a Tecnologia (FCT) under the project LA/P/0069/2020 granted to the Associate Laboratory ARNET, and the strategic project UIDB/04292/2020 granted to MARE - Marine and Environmental Sciences Centre. Publisher Copyright: © 2023 The Author(s)Achieving a broad analysis of construction and demolition waste (CDW) management without considering local scale dynamics, and its detailed characteristics, is a constraint that has made it challenging to optimally engage in an integrated assessment of the circular economy principles in the construction sector. In this sense, this research demonstrates that investing in local strategies is important, involving municipalities and micro and small construction companies. Firstly, the results reveal the importance of having controlled sites, under local responsibility, for the preliminary storage of CDW, creating in waste producers the habit of separating waste onsite, reducing costs and limitations for municipalities. Secondly, frequent supervision actions at construction sites are also important at this scale, as they facilitate progress in terms of encouraging compliance with mandatory legal procedures and good practices for CDW management. But it is easier to improve practice through direct onsite procedures than it is with bureaucratic legal requirements alone. Thirdly, procedural control, implemented by municipal technicians in conjunction with other strategies, also helps to promote CDW management, this being associated with processes of public and private construction works subjected to license or prior control, in opposition to what has been accomplished so far. But the research also demonstrated that regular awareness, training, and supervision actions might increase the likelihood of improvements in behaviour on the local scale, in the sense that stakeholders acquire new habits, which, over time, might lead to better results locally and, as a consequence, influence other scales of intervention.publishersversionpublishe

Carbon Footprint Analysis for the Waste Oil Management System in Portugal

The authors are grateful for the support they received from SOGILUB.Aims: The study analyzes the carbon footprint of the waste oil management system operating in Portugal to ensure the sustainable operation in the future. The analysis was carried out in 2011for the system that is composed of a treatment procedure collecting the treated oil for re-refining, followed by the production of expanded clay and recycling for electricity production. Methodology: Carbon footprint analysis was conducted by using the Umberto software 5.5 based on the concepts of life cycle assessment with respect to international standards (ISO). Within this context, the substances considered for such carbon footprint analysis are directly relevant to Intergovernmental Panel on Climate Change (IPCC, 2007). Results: The results showed that managing waste oils may contribute to the reduction of carbon footprint due to the avoided emissions of greenhouse gas through the reuse of treated waste oils. The carbon dioxide equivalent emissions from collection and treatment of waste oils would not outweigh such benefit earned from the substitution of virgin lubricant oil even though the use of treated waste oils for producing expanded clay may end up some more carbon dioxide emissions. Conclusion: The carbon footprint analysis in this study has shown the potential for improvements in the waste oil management system in Portugal. The most significant improvement that could be made is the increase of using treated waste oils for the expanded clay production. However, such a strategy would not be consistent with the waste hierarchy principle which dominates the current decision making in managing waste nationally.publishersversionpublishe

Local scale dynamics to promote the sustainable management of construction and demolition waste

2_(Des)construir_Economia_Circular). This work was also supported by the Portuguese Fundação para a Ciência e a Tecnologia (FCT) under the project LA/P/0069/2020 granted to the Associate Laboratory ARNET, and the strategic project UIDB/04292/2020 granted to MARE - Marine and Environmental Sciences Centre.On a local scale, municipalities often incur high costs as a result of the illegal dumping of construction and demolition waste (CDW), due to gaps in awareness and training, a lack of adequate oversight actions or infrastructure and equipment. Moreover, there is a loss of resources, failing to close the loop of the circular economy. Six participatory workshops were implemented in 2021, via videoconference due to the Covid-19 pandemic, in a rural Portuguese region, to understand the contribution of local scale dynamics in the promotion of CDW management from an operational perspective. Three of them were dedicated to municipal technicians (39 participants, on average) and the other three to representatives of micro and small construction companies (25 participants, on average). The results reveal that strategies must rely on investment in local solutions to optimise logistics and cost issues, cooperation between stakeholders, and improving the market for recycled aggregates. Also, support for information, awareness, and training is essential, focusing on good practices onsite and oversight procedures. Additionally, municipalities were involved in the prioritisation of legal framework issues, and micro and small construction companies concerning the determinants contributing for their behaviour change. These findings contribute to solving gaps in the literature, useful for researchers and decision-makers in rural or less developed areas.publishersversionpublishe

Caso de estudo: sistema de vidrões

Tese de doutoramento em Engenharia do Ambiente, especialidade em Sistemas SociaisO presente trabalho analisa os comportamentos de deposição selectiva por transporte voluntário, conjugando as perspectivas psicossomática e técnica, ambas fundamentais para o sucesso da reciclagem. Esta abordagem foi aplicada ao sistema vidrão, estando o trabalho dividido em três partes com objectivos específicos: 1) caracterizar os recicladores (REC) e os não-recicladores (NREC) e analisar o efeito da distância das habitações aos equipamentos de deposição selectiva nos comportamentos de reciclagem; 2) desenvolver um modelo de previsão dos comportamentos de reciclagem do vidro, MODEVIDRO, e testá-lo em grupos sócio-urbanos homogéneos; 3) complementar os conhecimentos sobre os comportamentos adquiridos de forma indirecta por questionário, com medições directas, através da análise da composição física dos resíduos produzidos e da monitorização do número de embalagens depositadas no vidrão

Moisture measurement in paper and cardboard packaging waste bales for recycling

Funding Information: Funding: This research was funded by Sociedade Ponto Verde (SPV) and was supported by the Marine and Environmental Sciences Centre (MARE), which is financed by national funds from FCT/MCTES (UIDB/04292/2020). Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Moisture content is a quality issue raised by recycling plants in the acceptance of paper and cardboard coming from waste streams. The current way to measure this parameter is by the oven drying method, which is a slow and invasive process, costing time and resources for the recyclers to do this type of quality control. An alternative to such a measurement technique is the use of plate-form devices which indirectly measure the moisture content using the dielectric properties of water and paper. This study has tested this method and developed a representative equation for the use of devices with these properties in the Portuguese market. For that, 48 wastepaper and cardboard bales were tested with both the traditional (oven drying) method and a commercial device equipped with dielectric technology. An equation that fits the studied reality (R2 = 0.76) was achieved, and possible problems regarding the use of this device were tested. The results showed that this type of device could be used as a time-and cost-saving, non-destructive and reliable method in the quality control of wastepaper and cardboard bales.publishersversionpublishe

Collection: the strongest link for a sustainable solid waste management

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A calculadora gráfica como instrumento para o desenvolvimento da argumentação matemática

A presente investigação tem como objectivo provar que a calculadora gráfica pode desempenhar um papel de instrumento mediador e facilitador no desenvolvimento da argumentação matemática, quando os alunos são estimulados a desenvolver tarefas de investigação em pequeno e em grande grupo. Para tal a professora investigadora elaborou uma tarefa de investigação, sobre o tema das funções racionais, que foi aplicada a uma turma do 11.º ano. A tarefa foi realizada primeiro em pequenos grupos e posteriormente em grande grupo, com a entrega final de um relatório individual. A metodologia adoptada foi de carácter qualitativo e descritivo. Neste estudo a calculadora gráfica revelou-se uma ferramenta fulcral para os alunos na medida em que os ajudou na compreensão da tarefa, assim como na validação ou rejeição das conjecturas que previamente foram formuladas, desenvolvendo a capacidade de argumentar em matemática. É de salientar, a importância da calculadora gráfica, do ponto de vista dos alunos, para o sucesso da investigação. A sua utilização permitiu construir e visualizar os gráficos de diferentes funções e, através da sua análise, formular conjecturas e tentativas de prova.Fundação para a Ciência e a Tecnologia (FCT

A argumentação matemática na resolução de tarefas com a utilização da calculadora gráfica : uma experiência numa turma do 11º ano

A presente experiência teve como objectivo estudar se as tarefas de investigação com a utilização da calculadora gráfica podem facilitar e proporcionar o desenvolvimento da argumentação matemática nos alunos. Para tal a professora investigadora elaborou cinco tarefas que aplicou a uma turma do décimo primeiro ano com o objectivo de estudar as funções racionais. Nesta comunicação apresenta-se apenas uma das tarefas. O trabalho desenvolveu-se inicialmente em pequenos grupos, posteriormente em grande grupo de discussão e finalmente com a elaboração de um relatório escrito individual que incluía uma reflexão. A metodologia adoptada foi de carácter qualitativo e descritivo. A aplicação da tarefa de investigação em grupo, permitiu tirar várias conclusões relativamente à argumentação matemática, ao trabalho colaborativo e à utilização de forma adequada da calculadora gráfica. A análise dos resultados obtidos evidenciou que a aplicação das tarefas de investigação, apesar das dificuldades iniciais, permitiu uma melhor compreensão e apropriação por parte dos alunos da turma do conteúdo programático relativo às funções racionais. Verificou-se também que os alunos ao longo do trabalho de investigação foram desenvolvendo o espírito crítico relativamente aos resultados que o visor da calculadora gráfica lhes mostrava