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Problems with recycling of lithium from unusable batteries
Brožek, Vlastimil ; Dufek, V. ; Němečková-Hrnčířová, M.
The article describes critical stage of LIB recycling, that is, safe opening of the batteries to permit subsequent thermal treatment. LIB contain volatile, toxic and explosive components in hermetically sealed metallic or glassy containers. In LIB electrolytes such as Li-MH, Li /CF Li/SO2, Li-ion or Li-ion-polymer, and also Li-MnO2, Li-SOCl2, Li2FeS2 and Lipon (lithium and phosphorus oxide-nitride), the following compounds can be identified: polypropylen carbonate, ethylen carbonate, dimetoxyethane, various glykol esthers, lithium perchlorate or lithium fluoride-phosphate solutions. These can increase the risk of explosion when heated. Most of LIB producers do not disclose the composition; thus, every new type of battery is a specific item, from the cleanup point of view. The positive information about less flammable or non-toxic components of new LIB types, such as fluorated aryles, polyacryl-nitryl gels or phosphorus chelatocomplexes, do not make the recycling issues easier.
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Photocatalytic aktivity of plasma treated titanium precursors
Brožek, Vlastimil ; Matějíček, Jiří ; Šrank, Z. ; Mastný, L. ; Janča, J.
Photoactive solid parts of chemical reactors could be produced via plasma deposition of boron carbide and titanium diboride using water-stabilized plasma torch WSP. Photocatalytic effectivity of TiC and TiB2 was measured, as well as those of their oxidation products gained at 450 and 1000°C on air as well as at 450°C in oxygen plasma. Photocatalytic effectivity of all studied substances was compared with those of plasma- treated TiO2 and Ti2O3, whose photocatalytic activity is known from plenty of practical applications.
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Nicotine destruction on different photoactive catalysators
Brožek, Vlastimil ; Mastný, L. ; Šrank, Z. ; Eliáš, M. ; Janča, J.
We built a testing apparatus that uses IR analysis to observe the decomposition rate of nicotine from cigarette smoke on spherical or planar catalysers prepared by plasma-thermal treatment of titania-based precursors. The photocatalytic efficiency of the products of plasma-thermal treatment of metallic titanium by the WSP® plasma generator was compared with standard anatase catalysers of the Degussa AV type when destroying nicotine by application of a 366nm UV light. The results permit to consider a construction of an efficient nicotine destruction facility.
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Rubidium and cesium from waste materials
Brožek, Vlastimil ; Dufek, V. ; Hrnčířová, M.
This paper is a continuation of work presented at Metal 2004, „Perspectives of exploitation of Czech lithium resources“, based on the MPO FF-P2/057 project. The results indicated that extensive analytical methods for lithium-containing waste materials (found in the Ore Mountains, especially around Cínovec/Zinnwald, Li content about 0.2%), after wolframite processing, permit also to trace the content of rubidium and cesium. These elements are gradually gaining industrial importance. Initially, this fact was used for routine analyses of samples from various locations, as the easily-determined Rb content was regularly 5:1 to Li content, which is far more difficult to determine. However, previous efforts to simplify the analyses led to different results from different laboratories. Thus, we decided to unify the methodology and explore the possibility of extracting these elements during lithium recycling. This would make the new technology more economical.
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Měření tvrdosti nehomogenních plazmových nástřiků
Čtvrtlík, Radim ; Stranyánek, Martin ; Boháč, Petr ; Jastrabík, Lubomír ; Hrabovský, Milan ; Ctibor, Pavel
Paper deals with testing of mechanical properties of plasma sprayed coatings TiO2 by Depth Sensing Indentation performed on measuring system NanoTest 600™. The NT600™ is a modular measuring instrument with unique design, which applies the loading force in horizontal direction. The platform can measure and evaluate hardness, elastic modulus, adhesion, wear, fracture and also dynamic properties. In the last years the new plasma spraying technology of ceramic and ceramic-metal materials has became as very convenient technique in many industrial and reconstruction processes. The investigated samples of plasma sprayed coatings were prepared in Institute of Plasma Physics of the Academy of Sciences of the Czech Republic. The goal of this paper is to contribute to deepening the knowledge in local distribution of mechanical properties in plasma sprayed coatings, especially of hardness and elastic modulus.
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Difuzní proud v hraniční oblasti oblouku měřený elektrickými sondami
Chumak, Oleksiy ; Hrabovský, Milan ; Kavka, Tetyana ; Kopecký, Vladimír
Electric probes were used for investigation of an intermediate layer between the arc and anode surface in regions outside the main current channel. Distributions of a diffuse current and the potential were measured. Resistance and heating of the intermediate layer by diffuse current were evaluated. It was found that not only the value of diffuse current strongly depends on distance from the arc but also the shape of the distribution and the position of the maximum of the current change with the distance. These trends can be explained by expanding of the plasma jet. Evaluated equivalent intermediate layer resistance shows widening of the conductive region in a stream wise direction. Variation of resistivity of the intermediate layer is much higher than variation of the potential drop on the layer. That means that distributed current as well as Joule heating of the layer are generally controlled by distributed resistance.
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Vodní a hybridní plazmatrony s plynovou a vodní stabilizací
Hrabovský, Milan
Plasma torches with water-stabilized arc (Gerdien arc) are utilized in plasma processing for specific applications. In water-stabilized torches an oxygen-hydrogen plasma jet is produced. The torches are characterized by very low mass flow rates and high power. Plasma enthalpy is thus several times higher than enthalpy of plasmas generated in gas-stabilized torches. High enthalpy is accompanied by very low plasma density. Also other plasma parameters substantially differ from the ones in gas torches. New type of plasma torch with combined stabilization of an electric arc by water vortex and gas flow was investigated. This hybrid water/gas stabilization offers possibility of adjustment of plasma jet parameters in a wide range from high enthalpy, low density plasmas typical for liquid stabilized torches to lower enthalpy, higher density plasmas generated in gas stabilized torches.
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Mapování teplotního a rychlostního pole ve volném proudu horkého plynu
Gregor, Jan ; Jakubová, I. ; Mendl, T. ; Šenk, J.
In the paper the measurements on hot gas mixture free jet are analyzed. The main interest is oriented on the analysis of the distribution of the individual species in the jet based on the vector form of the continuity and momentum equation. In the continuity equation the diffusion member is involved. To simplify the problem, the temperature and velocity fields are approximated by suitable functions. The calculation process is applied on the jet generated by a hybrid water stabilized plasma torch with argon added into the chamber of a plasma heater.
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Modelování směšování plazmatu vodní páry s parní atmosférou v tepelném plazmovém reaktoru
Hirka, Ivan ; Jeništa, Jiří ; Hrabovský, Milan
Two-dimensional CFD modelling of mixing of steam plasma jet with steam atmosphere in thermal plasma reactor has been carried out. Temperature of steam plasma is approximately 15 000 K and temperature of steam atmosphere is 400 K. Standard, RNG, and realizable k-e models were used for all simulations. Steam plasma and steam atmospheric properties were generated by the ADEP code. Results for temperature, velocity and density distributions are discussed and presented as images obtained from the FLUENT code, for currently used reactor geometry setup and plasma flow.
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Studium difuzního proudu na hranici oblouku pomocí elektrických sond
Chumak, Oleksiy ; Hrabovský, Milan ; Kavka, Tetyana ; Kopecký, Vladimír
Electric probes were used for investigation of an intermediate layer between the arc and anode surface in regions outside the main current channel. Distributions of a diffuse current and the potential were measured. Resistance and heating of the intermediate layer by diffuse current were evaluated.It was found that not only the value of diffuse current strongly depends on distance from the arc but also the shape of the distribution and the position of the maximum of the current change with the distance. These trends can be explained by expanding of the plasma jet. Evaluated equivalent intermediate layer resistance shows widening of the conductive region in a stream wise direction. Variation of resistivity of the intermediate layer is much higher than variation of the potential drop on the layer. That means that distributed current as well as Joule heating of the layer are generally controlled by distributed resistance.
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