Os resíduos da construção civil (RCC) constituem atualmente um dos maiores problemas das áreas urbanas, sendo a gestão adequada desse material um desafio para grande parte dos municípios brasileiros. Nesse contexto, os consórcios intermunicipais surgem como uma alternativa de viabilização de projetos, com base no princípio de que a busca de parcerias pode ser uma opção mais atrativa e econômica. Dessa forma, este trabalho teve como objetivo avaliar a viabilidade econômica de três cenários diferentes para a implantação de infraestruturas de gerenciamento e reciclagem de RCC para formação de um consórcio intermunicipal nos municípios pertencentes à Bacia Hidrográfica do Baixo Pardo/Grande (UGRHI 12). Por meio das visitas e entrevistas com gestores públicos, constatou-se que nenhum dos municípios da UGRHI 12 possui infraestrutura adequada para o gerenciamento dos RCC gerados. As análises de viabilidade econômica mostraram que o compartilhamento de uma usina de reciclagem de RCC, uma área de transbordo e triagem e um aterro se mostrou o cenário mais vantajoso, resultando em uma taxa interna de retorno de 78,79%, um valor presente líquido de R$ 29.094.983,16 e payback de um ano e sete meses. Entretanto, nos três cenários analisados, viu-se que a gestão compartilhada dos RCC pode ser viável e lucrativa, podendo trazer redução de custos e ganho de escala.

Urban environments contain and are part of a wide range of interconnected complex systems, including infrastructures and services. Rapid and often uncontrolled urbanization triggers distributive inequities and environmental injustices, posing urgent and interconnected challenges that demand inter- and transdisciplinary solutions. Despite architecture’s commitment to ‘sustainability’, its central role in urban systems and their dynamics as well as the discipline’s intersections with other disciplines remain relatively little explored. In this contribution, we focus on the water–energy–sanitation (WES) nexus in Brazil, drawing from transdisciplinary workshops, scoping reviews, and systems mapping. We propose a framework for the analysis of urban nexuses. This framework builds on transdisciplinary systems mapping for the identification of nexus components, nodes, and their interconnections. Our findings indicate that a nexus perspective allows us to identify challenges in urban nexuses, productive intersections with the knowledge and approaches from other disciplines, and possible solutions in collaboration with non-academic stakeholders. We advocate for an expanded professional field and a redefined sense of responsibility within the discipline.

Waste electrical and electronic equipment is a significant source of material that can contribute to reduce environmental impacts associated to extraction and discard stages; therefore, it is necessary to develop efficient recycling processes for components such as Printed Circuit Boards (PCBs). Current methods for PCB recycling may be optimized by previous disassembly of such components. In the work reported here, an especially designed and manufactured centrifuge was employed to disassemble PCBs from power supplies (PS-PCBs) and memory chips (ME-PCBs) of personal computers (PCs), through combination of hot air flow and centrifugal force. The results showed that the device was capable of separating tin solder, electronic components (EC) and PCB substrate, as long as hazardous components and plastic parts are previously removed. A scanning electron microscope (SEM) with combined energy dispersive X-ray (EDX) analyzer showed that the recovered solder had under 3%wt of contamination; therefore, it can be employed in the production of new soldering material, replacing the more commonly used solder dross. EC recovery rates were up to 94%wt for PS-PCBs and 32%wt for ME-PCBs, and once components such as inductors were not visibly damaged in the process, possibilities of reusing recovered components may be further investigated.