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Small Island Developing States (SIDSs) are faced with challenges such as reducing the share of fossil energy and waste landfilling. This work summarizes the main aspects of 53 SIDSs that constrain economic development, energy sources, and waste management strategies. An integrative bibliographical review is conducted to synthesize the state-of-the-art of waste-to-energy (WtE) strategies and compare the technologies in light of their suitability to SIDS. The findings show that considering the large amount of waste produced annually, WtE technologies are of the utmost importance to reduce ecological footprints (EFs) and greenhouse gas (GHG) emissions, and to increase the share of renewable energy with the installation of incineration plants with energy recovery to replace fossil fuel power plants. Although WtE is recommended for all SIDSs, the Atlantic, Indian Ocean, Mediterranean, and South China Sea (AIMS) countries exhibit higher population density (1509 inhab/km2) and a high share of fossil fuel in their electricity mix, so that there is greater urgency to replace landfilling practices with WtE. The estimation of potential power generation capacity (MWh) from annual municipal solid waste (MSW) in each SIDS as well as the reduced land area required demonstrate the feasibility of WtE technologies. Only 3% of the landfill area is necessary for buildings and landscaping associated with a WtE plant able to treat 1 million tons of MSW, considering a 30 year lifespan. Furthermore, incineration with energy recovery benefits from high penetration worldwide and affordable cost among thermochemical processes.

Interest in research on capillary barrier (CB) in regions with humid climates (tropical and subtropical) is increasing. One of the main advantages of such cover type is the greater flexibility regarding the materials that could compose it. A possibility is the use of construction and demolition wastes (CDW), which would contribute to the solution of CDW destination, a problem in urban centers. Thus, the present work aimed an experimental evaluation of CB cover with CDW in its composition. A CB cover system was reproduced in a physical model in acrylic box, with clay soil as capillary layer and CDW as capillary block, given its granulometric and hydraulic contrast. The layers were arranged with the usual landfill slope, of 1:3, and a very heavy rain, of 90 mm, was simulated. Three tests were performed on the flume model, in which initial CDW saturation degree (S0) was varied in 4,5%, 10,3% and 17,3%. Results indicate formation, indeed, of capillary barrier between the two used materials. The most efficient model was the one with lowest initial CDW S0, of 4,5%. As the CWD S0 increased, time of flow permanence at materials interface decreased, indicating a CWD S0 in which such capillary barriers no longer function effectively. Regarding percolation rate, the maximum for a 90 mm rainfall was 2,7%, which fits the landfill cover projects criteria consulted.

RESUMO: A sondagem SPT é a mais utilizada no mundo para estudo do solo, no entanto possui diversas fontes de incerteza em seus resultados. Uma alternativa para reduzir algumas dessas fontes de incerteza é o uso de equipamentos SPT com martelo automático. Nesse sentido, o presente trabalho teve como objetivo apresentar alguns dos efeitos resultantes do uso de equipamento automatizado em sondagens SPT. Para tanto, foram realizados registros da altura de queda do martelo com auxílio de câmera 4K (2160p) 30fps, assim como observações de campo dos dois métodos. Os resultados indicam maior homogeneidade nos valores de altura de queda medidos para o martelo automático, bem como menor dispersão e valor médio mais próximo ao da normativa brasileira (de 75 cm). Ademais, a sondagem automatizada apresenta vantagens em aspectos relativos à segurança do trabalho para os funcionários e otimização das equipes (redução de um colaborador) para o serviço. Em suma, os aspectos abordados nesta pesquisa reforçam a necessidade de maior atenção para o método de sondagem SPT automatizada no cenário nacional.

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