Properties of the fly ash from the Power Plant Dětmarovice from the point of view of their deposition in underground mines

Mining for the Purposes of Disposal Facilities, Requirements and Conceptions. Mining for the purposes of disposal can be instrumental in environmental protection in the future. Therefore the utilization of residues in the mining process has to be put into the foreground, whether they are a product of the mining activity itself or coming from other sources. It is possible to use the residual products as filling or building materials. Within the constantly increasing demand for building materials in the mines it is possible to combine the advantages that improve mine safety, rock mechanics and support with the secure long-term sealing of mineralized industrial residues in the lithosphere. Also the disposal of polluted, water-soluble and toxic or radioactive waste in a suitable geological formation underground can be realized ensuring long-term safety. This long-term safety is guaranteed by a multiple system of geological and technical barriers. The storage can b conducted in appropriate void space like chambers, caverns, drifts or boreholes with or without the opinion of retarding the material.Contribution is discussing the possibility of the deposition on fly ash produced by thermal power plants which are using low-grade brown coal as a fuel. Properties of fly ash were studied id detail on samples from Power Plant Dìtmarovice, northern Moravia.Results proved that fly ash can be deposited safely in underground

Aspects of classification of energy sources in terms of their position in the sector of the economy

The paper deals with the study of problems relating to classification of energy sources, in particular from the perspective of their position in covering of energy needs of country or economic sector. Classification of energy sources is currently often viewed as a set of fixed categories, but taking a closer look and making a deeper analysis can defined a number of criteria that might determine the final importance and position of resources in the context of complex connections. The composition of energy sources was analysed on a sample of nine countries, which was conceived with the intent to cover various kinds of standard and specific types of energy mixes. In the paper, several criteria for assessing the quantitative and qualitative nature of energy sources were defined. Sectoral, temporal, spatial and scale framework for the validity of the assessment were also defined. In the analysis, the attention was focused on the electricity sector and partially on the sector of transport. The results of the analysis indicate that in different conditions, the same energy source or group can be categorised in a different way, which may have a significant impact on the application of legislation in terms of the use of control, support and regulatory instruments. The analysis took into account in particular the aspects, which complement the recently published papers analyzed this complex issue.Web of Science21429728

Assessment of mining activities with respect to the environmental protection

This paper deals with the impact of mining on the environment. Coal mining is still among the most widespread and most intense mining activity, which disturbs the landscape around us bringing regional environmental, economic and aesthetic problems. However, for many countries in the world, including the Czech Republic, deposits of raw materials play an important role, especially for purposes of producing electricity and thermal energy. At the same time, growing emphasis laid on the environmental protection can be observed worldwide. To meet the increasing ecological demands, it is reasonable to consider the most significant aspects of mining activities from the environmental point of view, as well as to consider the possibilities of the abandoned mines utilization as possible waste dumps. Parts of this problem consist in: the monitoring, environmental impacts assessment of exploration and mining activities and waste disposal mining, which may significantly contribute to the environmental protection in the future. Several parameters that can significantly affect the usability of the waste disposal mining, such as geological structure, hydro-geological conditions, material composition and physical and mechanical properties of rocks are discussed in detail in this work. The article also includes a practical example of Environmental Impact Assessment process for the particular activity of OKD stock company, which is the only producer of hard coal (bituminous coal) in the Czech Republic. Its coal is mined in the southern part of the Upper Silesian Coal Basin - in the Ostrava-Karvina coal district. KeywordsWeb of Science221937

Soil contamination by heavy metals at Libiola abandoned copper mine, Italy

Exploitation of ores has surely represented a risk for contamination of environmental matrices for a long time. This paper reports the results of a study concerning soil contamination by heavy metals at Libiola abandoned copper mine (Italy). This deposit has surely got special importance in Italy because of its historical, environmental and mining features. From a historical viewpoint, Libiola deposit was known since Copper Age, with maximum exploitation at the end of the 19th century. Our investigation plan was elaborated in order to characterize the environmental matrices there, and it provided for inspection of the zones (included in the valley of Gromolo stream) which, according to our preliminary studies and according to literature, could be most affected by past mining activity. Within our selected zones, some soils (even cultivated) were collected in order to check their contamination by heavy metals. Results from the analysis of the collected soil samples showed that the content of heavy metals often exceeds limits provided by the Italian Law 152/06. The knowledge of situation concerning pollution can give useful indications about the influence of mining activities on the surrounding environment, and it can also be valid support in order to organize an optimal future use of the studied mining area, which has been abandoned since its closure (1962).Web of Science23334533

Poliuretanska pjena kao agregat za toplinske izolacijske žbuke i laki beton

The contribution describes the use of polyurethane foam after the end of its life cycle as an aggregate both for thermal insulating mortars for various wall surfaces and for lightweight concrete. The structure and the physical and mechanical properties of thermal insulating mortar are described here. The verification of application of thermal insulating polyurethane mortar in the thickness of 50 ÷ 70 mm to a reference building, where external walls were insulated, is provided further. The second important area dealt with in this contribution is that of lightweight concrete, for which polyurethane foam of grain size of 0,125 ÷ 6 mm is used as an aggregate. The physical and mechanical properties of polyurethane concrete of various densities and an example of its prefabrication are presented.Prilog opisuje uporabu poliuretanske pjene nakon završetka njezinog životnog ciklusa kao agregata i za toplinske izolacije žbuke za različite zidne površine i za laki beton. Ovdje su opisane struktura i fizikalno-mehanička svojstva toplinske izolacijske žbuke. Nadalje se daje provjera primjene toplinske izolacijske poliuretanske žbuke u debljini 50 do 70 mm na referentnoj zgradi, kod koje su vanjski zidovi izolirani. Drugo važno područje kojim se bavi ovaj prilog je da se poliuretanska pjena veličine zrna od 0,125 do 6 mm koristi kao agregat kod lakog betona. Prikazana su fizikalna i mehanička svojstava betona od poliuretana različitih gustoća i primjer njegove prerade.Web of Science19367266

Comparison of heavy-metal bioaccumulation properties in Pinus sp and Quercus sp in selected European Cu deposits

Heavy-metal contamination of Pinus pinaster, P. sylvestris, Quercus robur, and Q. rotundifolium was studied in four abandoned historic Cu deposits from Italy (Libiola, Caporciano), Portugal (Sao Domingos), and Slovakia (L'ubietova). The highest Cu and Mn contents in anthropogenic soil were described in Libiola and Caporciano whereas the highest Pb, Zn, As, and Sb contents in Sao Domingos. The anthropogenic soil in L'ubietova shows the highest Co contents. The area of Sao Domingos is the most acidified. There are important differences between the bioaccumulation of plants from individual deposits. Bioavailability of the heavy metals is generally independent of the pH values. The high Ca and Mg contents in soil are able to block the transport of heavy metals to the plant tissues. The bioconcentration factor values of all plant taxa, in all deposits, indicate a predominant strategy of excluders. Only Ag shows excellent bioconcentration ability. In L'ubietova, Pinus sylvestris has a strategy as an accumulator of Pb (2.43) and Zn (2.49); Pinus pinaster of Mn (4.97), Cd (1.85), and Co (5.62) and Quercus rotundifolium of Mn (3.54) in Sao Domingos. The predominantly low translocation factor values indicate that in most cases the heavy metals are accumulated in roots; only in a few rare cases do they migrate to shoots (e.g. Zn in Pinus sp. from all localities, Co in P. pinaster in Sao Domingos).Web of Science16878

Polyurethane foam as aggregate for thermal insulating mortars and lightweight concrete

Prilog opisuje uporabu poliuretanske pjene nakon završetka njezinog životnog ciklusa kao agregata i za toplinske izolacije žbuke za različite zidne površine i za laki beton. Ovdje su opisane struktura i fizikalno-mehanička svojstva toplinske izolacijske žbuke. Nadalje se daje provjera primjene toplinske izolacijske poliuretanske žbuke u debljini 50 do 70 mm na referentnoj zgradi, kod koje su vanjski zidovi izolirani. Drugo važno područje kojim se bavi ovaj prilog je da se poliuretanska pjena veličine zrna od 0,125 do 6 mm koristi kao agregat kod lakog betona. Prikazana su fizikalna i mehanička svojstava betona od poliuretana različitih gustoća i primjer njegove prerade.The contribution describes the use of polyurethane foam after the end of its life cycle as an aggregate both for thermal insulating mortars for various wall surfaces and for lightweight concrete. The structure and the physical and mechanical properties of thermal insulating mortar are described here. The verification of application of thermal insulating polyurethane mortar in the thickness of 50 ÷ 70 mm to a reference building, where external walls were insulated, is provided further. The second important area dealt with in this contribution is that of lightweight concrete, for which polyurethane foam of grain size of 0,125 ÷ 6 mm is used as an aggregate. The physical and mechanical properties of polyurethane concrete of various densities and an example of its prefabrication are presented

Hazards of Heavy Metal Contamination at L’ubietová Cu-Deposit (Slovakia)

AbstractThe dump-fields Podlipa and Reiner at L’ubietová abandoned Cu-(Ag) deposit is situated at the boundary of the village settlement. The heavy metal contamination of the technogenous sediments and soils at the investigated dump-field show irregular planar distribution. Also the heavy metal content in the surface water, drainage water and in the groundwater was studied both in the dry as well as during the rainy periods. The speciation of As and Sb showed that there are present both As3+, Sb3+ as well as the less toxic As5+ and Sb5+ species. In the sediments prevail As5+ and Sb5+ species while in the water is dominant the As3+ and Sb3+ form. The article also presents results of the plant tissue degradation study in heavy metal contaminated conditions and compares them with those from reference sites. The cementation process causes substitution of iron by copper. The technogenous sediments and the contaminated soil of the dump show only very limited acidification potential. The installation of the Fe0-barrier seems to an acceptable solution for cleaning of the underground water

Comparison of soil contamination at the selected European copper mines

ABSTRACT: This article reports the results of a study concerning contamination of the dump-fields by potentially toxic elements at five abandoned copper mines: Ľubietová, Špania Dolina (Slovakia), Libiola, Caporciano (Italy) and São Domingos (Portugal). This paper offers an updated description of soil contamination at the individual deposits and indicates a possible solution of the derived environmental problems. Contamination of technosoils by PTEs at the dump-fields shows an irregular spatial distribution of Fe, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Sb and Pb. Contents of PTEs often exceed both national and EU law limits. Whereas at Ľubietová, Špania Dolina and Caporciano the environmental risk is limited, at Libiola and São Domingos it seems to be very heavy. The technosoil (slag) of the dump-fields is not well aerated and the soil colloids have (except for Špania Dolina) negative surface charge, so they are suitable for PTEs sorption. The main environmental risk in the mining area of Sao Domingos district is the long time formation of acid mine drainage water and the high Zn, As and Pb contents. The release of PTEs to the environmental components may be limited by phytostabilization and immobilization of metals, by suitable admixtures into the technosoil/slag. The environmental situation at Caporciano is not so compromised as at São Domingos mining area. Phytostabilization will be able to stop erosion, and installation of wetlands under the dump will stop the release of Cu to the environment.info:eu-repo/semantics/publishedVersio

Využití sigmoidních funkcí k modelování produkce zlata Jižní Afriky

Sigmoid functions were used to approximate the cumulative gold production curve of Southern Africa and to extrapolate them into the future. Southern Africa was chosen because one third of the historic global world gold production comes from the Witwatersrand basin area, and also because the peak gold point was already reached in 1970. All models give a good agreement with reality, when the negative effects of World War II and the positive effects of the apartheid boom 1950 - 1970 are compensated for. From today's viewpoint the Gompertz function was found to give the best model, although this model implies the peak occurred 10 years earlier and due to the apartheid boom was about 300 tons higher. It also shows that the production could possibly rise again in the future to a level of 400 or even 500 metric tons a year. Hence, a biomodal production curve with at least two peak points could be observed in the future. Mathematical results are discussed in respect to the political and economic history of this country.K bližšímu představení celkové produkce zlata v Jižní Africe a její extrapolaci do budoucnosti byly použity Sigmoidní funkce. Jižní Afrika byla vybrána, protože na jedné straně pochází jedna třetina celosvětové historické produkce zlata z regionu Witwatersrand, na druhé straně byl vrchol produkce zlata dosažen už v roce 1970. Všechny modely se dobře shodují s realitou, pokud vypočítáme negativní vlivy druhé světové války a pozitivní vlivy rozmachu apartheidu v letech 1950-1970. Gompertzova funkce představuje z dnešního pohledu nejlepší model, i když podle tohoto modelu vychází vrchol o deset let dříve a, vlivem rozmachu apartheidu, o 300 t výše. Ukazuje taky, že by produkce mohla ještě jednou vzrůst na 400 až 500 tun za rok. Tak by mohla v budoucnosti vzniknout bimodální produkční křivka s nejméně dvěma vrcholy. Jsou diskutovány matematické modely s ohledem na politický a ekonomický vývoj země