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Optimal methods used in the analysis of waste material resulting from mining and processing of mineral resources that allow to assess the potential impact of waste on the environment, based on binding environmental laws regulating potential commercial utilization of waste were investigated. The paper is concerned mostly with mineral waste, constituting about 80% of all industrial waste generated. According to the principles of sustainable waste management, waste storage is considered to be the last resort. However, every year over 20% of the total amount of industrial waste generated is stored. That makes the amount of the already deposited materials, coming from the time when the commercial utilization was not common in Poland, even more considerable. When it comes to extensive, i.e. regarding great quantities, and long-term usage of industrial wastes, the identical composition of waste material coming from different batches is of the essence. Unfortunately, this condition is not always fulfilled, therefore chemical composition analyses need to be carried out for monitoring purposes. For the same reason the waste material used should also be tested to check whether the parameters of a given batch are within the limit values defined by the standards. Described methods are intended to facilitate waste characterisation with respect to their effect on the environment when used for commercial purposes. An individual method is never good enough to determine the full extent of environmental impact. It is therefore recommended to apply several methods in a logical sequence, depending on the type of waste material and its purpose.
In this work, characterization of dolomite powder was carried out in order to specify possible industrial applications. After the technological use of dolomite aggregates, the remaining fine powder becomes a waste. Raw and calcined powder samples were subject to mineralogical, textural and chemical studies involving leaching tests. The results of the calcination process indicate that the carbonate minerals present in the material sample undergo complete decomposition to form oxides. After the calcination, the material is practically non-porous, and its surface area is more than five times lower than that of the raw material. However, due to the high content of calcia in the calcined sample (CaO > 45% wt.), the material cannot be used as an additive in cement. The leaching tests showed that the concentration of metals released from the dolomite powder is low enough to classify the material as hazardous waste according to the TCLP test. Moreover, the concentration of metals that can get into the environment does not exceed permissible values as set by Polish law. Thus, it is recommended and justified to carry out detailed tests for the purpose of environmental protection; i.e. wet flue gas desulfurization, heavy metals absorption, and CO2 capture.
Celem pracy była wstępna charakterystyka (mineralogiczna, chemiczna, teksturalna) odpadów poflotacyjnych, stanowiących surowiec uboczny (odpadowy) przy uzyskiwaniu koncentratów cynkowo-ołowiowych, pod kątem dalszych analiz nad możliwością ich perspektywicznego (eksperymentalnego) wykorzystania jako sorbentów gazów kwaśnych (SO2 i CO2). Składowisko tych odpadów jest własnością ZGH 'Bolesław' w Bukownie. Materiał badawczy stanowiła próbka odpadów poflotacyjnych pobrana ze stawu osadowego nr 1, leżącego w południowej części Stawu Zachodniego. Charakterystyka wytypowanych do badań materiałów obejmowała podstawowe badania mineralogiczne (XRD, SEM-EDS), analizy chemiczne (oznaczenie zawartości wilgoci analitycznej, zawartości strat prażenia, podstawowego składu chemicznego, jak też pierwiastków śladowych) oraz wyznaczenie podstawowych parametrów teksturalnych (powierzchnia właściwa BET, rozkład i wielkość porów). Badania mineralogiczne wykazały, że materiał odpadowy stanowią głównie minerały węglanowe (w przewadze kalcyt, dolomit, ankeryt) oraz minerały stanowiące pozostałość po niewyflotowanych kruszcach (w przewadze galena, sfaleryt). Analiza chemiczna pozwoliła stwierdzić, iż w analizowanej próbce dominują związki wapnia, magnezu i żelaza uwarunkowane przewagą minerałów węglanowych w badanych odpadach. Wśród pierwiastków śladowych przeważa arsen, następnie mangan i bar, występujące jednak w ilości nie przekraczającej 1%. Analiza teksturalna wykazała, że materiał badawczy charakteryzuje się niską powierzchnią właściwą i dużymi rozmiarami cząstek. Przeprowadzone badania sugerują, że analizowany materiał charakteryzuje się ubogimi właściwościami adsorpcyjnymi, aczkolwiek mógłby on znaleźć zastosowanie w metodach odsiarczania, jak też neutralizacji dwutlenku węgla (karbonizacja). Należałoby jednak w tym celu przeprowadzić dodatkowe badania wymywalności metali ciężkich w środowisku kwasowym, jak też zastosować domieszki innych składników, takich jak cement czy zeolity, w celu immobilizacji niebezpiecznych składników odpadów.
The aim of this study was a preliminary characterization (mineralogical, chemical, textural) of flotation wastes - which are the by-product of zinc-lead concentrate extraction - from the stand point of their further prospective (experimental) use as sorbents of acid gases (SO2 and CO2). The landfill sourced for the wastes used in this study was owned by ZGH 'Bolesław' in Bukowno. The research material consisted of a sample of flotation wastes taken from alluvial pond No. 1, lying in the southern part of the Western Pond. Characterization of the material selected for testing included the following: basic mineralogical (XRD, SEM-EDS) and chemical analysis (determination of analytical moisture content, loss on ignition, basic chemical composition, and content of trace elements), as well as the identification of basic textural parameters (BET specific surface area and pore size distribution). Mineralogical studies showed that the waste material consisted mainly of carbonate minerals (primarily calcite, dolomite, ankerite) and minerals present in the residuum after ore flotation (primarily galena and sphalerite). The chemical analysis indicated that in analyzed samples, calcium, magnesium, and iron components are predominant. They are conditioned by carbonate minerals which predominate in the studied waste. The most significant trace elements were arsenic, followed by manganese, and then bar - present only in quantities not exceeding 1%. Textural analysis showed that the test material has a low surface area and large particle size. The research suggests that the analyzed materials have poor adsorption properties, although they could be used in desulfurization as well as the neutralization of carbon dioxide (carbonation). However, it is necessary for this purpose to conduct additional studies of heavy metals' leaching in an acidic environment, in addition to applying the admixture of other ingredients to the flotation wastes, such as cement or zeolites, to immobilize hazardous waste components.
Mineralogical and chemical analyses of the historic objects found in the Katyn graves have been done. The analyses were aimed at identifying processes leading to destruction of the historic objects and at development of technology preventing their further destruction. Analyses with the use of digital and scanning (electron) microscopes as well as chemical EDS analyses were carried out. Observations showed that the examined objects undergo several processes of different degree of intensity. The main process observed in the examined objects (their plastic parts) is a kind of recrystallization, that is polymer’s structure ordering. Fragments of the polymer shrink, which results in formation of systems of fractures leading to the destruction of the material. Besides, the examined materials undergo condensation of polymers (ageing of polymer), oxidation and migration of foreign substances into the structure of the examined objects. Research results and information about celluloid, ebonite and resin (toothbrush) show that the best way to protect the relics is vacuum packaging in transparent plastic bags.
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