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In the present study, the establishment of decision-making criteria and a novel and robust interdisciplinary approach for systematically characterizing effects of uncertainties in social determinants of municipal solid waste management using an important fuzzy logic methodology is demonstrated. The primary goal is to highlight the social benefits of this waste management option such as job creation, hygiene and health protection, and working safety as well as to indicate certain side effects occurring during waste processing (odor and leachate production, social trust). The current research is based on a social survey in an agro-industrial region, Thessaly, Greece, and indicates a set of diversified key factors that are related to public acceptance of municipal waste management schemes. These features are input to Kohonen Self-Organized Maps (a special type of Artificial Neural Networks) for clustering residents according to their social perception and attitudes in terms of solid waste collecting and recycling. Both analyses highlight the environmental concern, social perception, hygiene and health, economic status, and lifestyle as the primary social determinants in affecting the public attitudes towards recycling. In both cases, these soft computing techniques seem to outperform the classical statistical and logical regression methodologies and become very promising in accurately predicting waste management practice and possibly other environmental behaviors. [ABSTRACT FROM AUTHOR]

Safe management of hazardous metals deriving from solid wastes constitutes an important environmental challenge. In the present study, recent progress in the stabilization/solidification of heavy metals from various solid wastes into ceramics and glass-ceramic materials is reviewed. Coal/lignite-fired power plant fly and bottom ashes, steel industry by-products, metallurgical and urban/municipal wastewater sludge, and pharmaceutical wastes are included. The environmental behavior of the ceramics produced is studied via several leaching tests and ecotoxicological analyses. The goal is to assess the potential of these materials for retention of pollutants into their microstructure, for safe use as building materials. These objectives are in line with green chemistry and sustainable development principles. Moreover, the aim of turning waste into useful feedstock for another industrial sector towards symbiosis, ample coordination, and circular economy, is strongly encouraged by current environmental policies. Such secondary resources can be considered as substitute materials in ceramics production, as they contain useful oxides. However, the presence of heavy metals remains a significant environmental issue. Possible leaching of pollutants caused by rain from construction materials incorporating solid wastes would lead to contamination of surface and subsurface water, thus raising critical environmental concerns. Inertization of potentially hazardous metals into environmentally-friendly ceramics and glass-ceramics is shown to be feasible, as concentrations of these elements in the leachates remain within acceptable limits. Certainly, this also depends on the leaching method employed and system parameters. In conclusion, stabilization of these elements into ceramic matrices can be an effective and beneficial alternative for protecting human health and the environment. [ABSTRACT FROM AUTHOR]

The aim of this work was to test CFB-derived fly ash for its potential to get utilised in ceramic tiles-manufacturing by applying the sintering technique. The tested specimens were moulded using extrusion and fired at 1,050°C; a laboratory pilot-plant simulation of the industrial brick fabrication process was applied and the produced materials were afterwards tested for their microstructure and physical properties. Different types of clays were selected and characterised and various clay-ash mixtures were prepared. Plasticity after mixing with water as well as extrusion of the compact specimens and their drying behaviour were evaluated. Water absorption and mechanical strength of fired specimens were determined and evaluated as a function of the percentage FA content. Results showed that large-scale production of CFB FA-containing bricks is feasible, as their mechanical properties were not significantly harmed, while any possible detrimental effect on the other properties of the synthetic bricks appeared to be relatively restricted. [ABSTRACT FROM AUTHOR]