The objective of this research work is to assess the viability of manufacturing ceramic bricks with sludge from a water treatment plant (WTP) for use in real-world applications. Sludge was collected from settling tanks at the Bolonha WTP, which is located in Belém, capital of the state of Pará, Brazil. After dewatering in drainage beds, sludge was added to the clay at a local brickworks at different mass percentages (7.6, 9.0, 11.7, 13.9 and 23.5%). Laboratory tests were performed on the bricks to assess their resistance to compression, water absorption, dimensions and visual aspects. Percentages of 7.6, 9.0, 11.7 and 13.9% (w/w) of WTP sludge presented good results in terms of resistance, which indicates that technically, ceramic bricks can be produced by incorporating up to 13.9% of WTP sludge.

Urban and industrial effluents, stormwater, road runoff, agricultural runoff, urban or mine waste deposits and fuel storage sites can lead to the contamination of water sources with compounds that are hard to biodegrade, such as heavy metals, whose removal requires advanced and expensive technologies. The Sustainable Development Goals (SDGs) established by the UN and the current requirements in terms of energy efficiency, reduction of carbon emissions, water reuse, waste valorization and preservation of public health, have led to a rethink concerning the typology of technologies for the treatment of water and the production of drinking water. Electrocoagulation (EC) stands out in this scenario due to its high efficiency in the removal of several pollutants, production of low sludge volumes and adaptability to the use of renewable energies. This is in addition to the ease with which it can be combined with other water treatment technologies. This work presents a literature review to systematize the use of EC for the removal of transition metals in water to produce drinking water, since these elements are present in several natural water sources and are parameters used in the legislation of many countries for the quality control of drinking water. The works found were analyzed in detail, and relationships between pre-set variables and categories were determined through regression analysis. Generally, it was found that EC is a highly efficient technology for the removal of transition metals in water (above 75% for most metals), specifically through parallel plates technologies with iron and aluminum electrodes with a minimum spacing of 1 cm and density minimum applied current of 10 A/m².

A urbanização e a falta de planejamento nas grandes cidades geram diversos impactos, entre eles o aumento da taxa de escoamento pluvial, devido a impermeabilização dos solos. Para se mitigar tais impactos, além das técnicas de drenagem urbana convencionais, surgem as novas tecnologias de Low Impact Development (LID), que visam o maior controle de impactos urbanos relacionados à água pluvial. Dessa forma, o presente artigo visa realizar um levantamento nas Unidades Federativas (UF) brasileiras, identificando as técnicas LID presentes na legislação, seja federal, estadual ou municipal. Após a análise, foram encontradas leis com presença de técnicas LID na maioria das UFs brasileiras, em alguns locais até 4 tipos diferentes de técnicas. Além disso, a maioria dos instrumentos analisados se referem aos reservatórios de detenção e retenção (40,5%), seguido de áreas verdes permeáveis e da captação e aproveitamento das águas pluviais, já as técnicas de telhado verde e trincheiras de infiltração ainda são pouco representativas, mas cresceram bastante nos últimos anos. Desta forma, verifica-se que estas tecnologias começam a ganhar espaço, no entanto, também é exposto a necessidade da crescente regulamentação das técnicas LID como ferramenta de planejamento, visando melhorar o desempenho dos sistemas de drenagem das águas pluviais nos centros urbanos do Brasil.