The influence of beech bark concentrations as filler in urea-formaldehyde (UF) adhesives was investigated relative to the composite forming process and selected properties of final 5-layer beech plywood. Beech bark was used as filler to lower the wood processing waste production and decrease formaldehyde emissions. A combination of UF adhesives filled with different beech bark concentrations as the adhesive was used. Three different concentrations of beech bark, 15 wt.%, 20 wt.%, and 25 wt.% were used in the experiment. Urea-formaldehyde adhesive filled with 20 wt.% technical flour was used as a reference sample. The effect of the filler was studied via its temperature profile during pressing, mechanical properties in bending, water absorption, thickness swelling, and formaldehyde emissions after pressing. The time needed to reach the temperature between the beech veneers, at least 105 °C, which was equal to the final temperature filler-adhesive-wood matrix cross-linking, was also investigated during the pressing process. The measurements of the free formaldehyde emissions showed that for samples with non-zero bark concentrations there was a decrease of formaldehyde emissions by at least 46%.

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Abstract:In Slovakia, 35% of buildings are older than 50 years but most newer buildings built before 1990 have greater energy consumption. Some other countries also have similar problems. The growing importance of energy saving in buildings can be, in the case of new and old residential buildings (RB), achieved by lowering thermal energy consumption most often by application of polystyrene insulation on the external walls and roof and the exchange of wood window frames for PVC (polyvinyl chloride) windows. The novelty of the article for Slovakia and some other central European countries consists in using the life cycle assessment (LCA) method for the objective assessment of the environmental benefits of the selected systems of wall insulation, as well as of energy savings in various time intervals of insulation functionality (up to 20 years). LCA software SimaPro (LE Amersfoort, The Netherlands) was used with ReCiPe and IMPACT 2002+ assessment methods to quantify the total environmental impact at selected endpoints and midpoints (IMPACT 2002+) of basic structural materials of an RB and its energy demand-heat consumption (hot water heating, central heating) before the application of insulation and thermal energy saving (TES) after application of insulation to its external walls, roof, and the exchange of windows. The data we obtained confirmed that the environmental impact of the polystyrene insulation of external walls, roof, and exchange of windows of one residential building (RB) in the first year after insulation is higher than the reduction caused by achieving a TES of 39%. When taking a lifespan of 20 years into consideration, the impact over the life cycle of the building materials is reduced by 25% (global warming: −4792 kg CO 2 eq; production of carcinogens: −2479 kg C 2 H 3 Cl eq; acidification: −12,045 kg SO 2 eq; and aquatic eutrophication: −257 kg PO 4 P-lim). The verified LCA methodology will be used for comparative analysis of different variants of thermal insulation of buildings, and their functionality in the long term, while taking into account local specifics and the preparation of environmental product declarations.

The main purpose of this study is to evaluate the reuse of refractory brick wastes (RWB)

This paper focuses on research concerning the ecotoxicological properties of granulated slag from the pilot production of gray iron with red mud addition and concrete composites with the application of this slag. Red mud is a hazardous waste generated in the production of aluminium oxide. Negative ecotoxicological tests are, therefore, one of the basic prerequisites for the ability to use granulated slag from gray iron pilot production. Granulated slag and concrete composite samples with various ratios of granulated slag have been subject to ecotoxicity tests: determining root growth inhibition in the highly-cultivated plant Sinapis alba, and determining acute toxicity in Daphnia magna. The results of ecotoxicological testing of granulated slag from gray iron standard production and gray iron pilot production with the additive were, according to the standard (STN 83 8303), negative. Additionally, the results of ecotoxicological tests of concrete composites were negative, with the exception of a 50% substitution of fine aggregate with slag from gray iron pilot production.

The aim of this manuscript is to provide an environmental assessment of the creation and use of waste foundry sand (WFS) via an LCA in a foundry for grey cast iron. A life cycle impact assessment was carried out using SimaPro 8. This environmental analysis assessed the impact of creating waste foundry sand (WFS) in a foundry, Hronec (Slovakia, Central Europe). According to BREF, this foundry is classified as an iron foundry with a production capacity greater than 20 t/day with processes typical for grey cast iron foundries. Molten metal is poured into single-use sand moulds. We identified those factors influencing the creation and use of WFS which significantly affect the quality of the environment. The use of WFS from the production of cores in regenerated moulding mixtures with installed circuits brings marked minimisation of material and energy inputs in the processes of creating WFS and it positively influences the consumption of resources and the quality of the ecosystem. Space for lessening the impact of WFS processes upon the consumption of resources and ecosystem quality is mainly found in recycling WFS in the building sector. In the next step, it is necessary to thoroughly verify the eco-toxicological properties of not only the created WFS and other foundry waste, but mainly the building products for which this waste is used. In terms of transportation, it is important that waste is recycled at local level. The processes of creating WFS have a marked influence upon all the selected waste categories (consumption of resources, ecosystem quality, human health). By minimising material inputs into processes and the effective adjustment of production technology, a foundry can significantly lessen the impacts of processes for creating WFS upon the environment.

The bottom ash from municipal solid waste incineration is the most important by-product, in terms of energy recovery from municipal solid waste. Safe treatment and reuse of this bottom ash in construction materials is one of the ways of its effective use. The specific use precedes the study of the properties of the bottom ash from municipal solid waste incineration. In this study, samples of bottom ash were examined via sieve analysis, basic chemical parameters, ecotoxicological property analysis and determination of heavy metals (As, Cd, Cr, Cu, Pb, Ni, Zn). The sieve analyses of samples showed different contents of individual fractions. Ecotoxicological tests for acute toxicity on Daphnia magna in the raw aqueous extract showed positive results mortality of all individuals after 24 hours. The toxic effect of bottom ash was confirmed by the content of heavy metals.

The main objective of this paper thesis is to determine the environmental impact of two houses made of two alternative materials - a wooden and a brick house - using a Life Cycle Assessment (LCA). By comparing the material composition of their design to determine the environmental impacts of global warming, human health, consumption of resources and ecosystem quality. An overall comparison showed that the materials for the construction of a wooden house have less negative impact on the environment than materials for the construction of a brick house. Using the GWP method, results show that the materials for the construction of a brick house leave twice the carbon footprint in the environment than materials for a wooden house. This resultant state is mainly due to the use of natural materials in the wooden house (wood, fibre insulation), unlike the materials used in the brick house (ceramic masonry, insulation from stone wool) and so on.