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Radium removal from mine waters with the application of barium chloride and zeolite: comparison of efficiency

Chałupnik Stanisław, Wysocka Małgorzata, Chmielewska Izabela, Samolej Krzysztof

Journal of Sustainable Mining

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2019

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Vol. 18, iss. 4

174--181

EN

In several coal mines in the Upper Silesian Coal Basin (USCB), in Poland, radium removal from mine water was necessary in order to mitigate the negative results of radium release with mine effluents. The most efficient method of radium removal was based on the application of barium chloride, implemented in full technical scale in two Polish collieries. Removal efficiency exceeding 95% of the initial activity was achieved. The technology was implemented in full technical scale in two collieries. The problem was that barium chloride is dangerous to health and moreover continuous use of the powdered chemical was required to achieve good results. Therefore, the possible application of zeolite for radium removal was tested in laboratory experiments. This passive technique would be less hazardous for miners and would not require full-time supervision meaning it would enable a reduction in workload. The main goal of the investigations described in this paper was to check the capability of zeolites to remove natural radionuclides from mine waters and compare the removal efficiency of radium isotopes with the results obtained from the application of barium chloride solution for the same purpose.

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Kinetics of the continuous reaction crystallization of barium sulphate in BaCl2 - (NH4)2SO4 - NaCl - H2O system - neural network model

Piotrowski K., Koralewska J., Wierzbowska B., Matynia A.

Polish Journal of Chemical Technology

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2009

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Vol. 11, nr 4

13-19

EN

One of the main toxic components of post quenching salts formed in large quantities during steel hardening processes is BaCl2. This dangerous ingredient can be chemically neutralized after dissolution in water by means of reaction crystallization with solid ammonium sulphate (NH4)2SO4. The resulting size distribution of the ecologically harmless crystalline product - BaSO4 - is an important criteria deciding about its further applicability. Presence of a second component of binary quenching salt mixture (BaCl2-NaCl) in water solution, NaCl, influences the reaction-crystallization process kinetics affecting the resulting product properties. The experimental 39 input-output data vectors containing the information about the continuous reaction crystallization in BaCl2 - (NH4)2SO4 - NaCl - H2O system ([BaCl2]RM = 10-24 mass %, [NaCl]RM = 0-12 mass %, T = 305-348 K and τ = 900-9000 s) created the database for the neural network training and validation. The applicability of diversified network configurations, neuron types and training strategies were verified. An optimal network structure was used for the process modeling.

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Wpływ chlorków baru i strontu na właściwości elementów gipsowych

Malata G., Pichniarczyk P.

Cement Wapno Beton

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2009

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R. 14/76, nr 2

97-102

PL

W pracy zbadano wpływ chlorków baru i strontu na wytrzymałość stwardniałych zaczynów gipsowych. W wyniku nawilżania chlorkiem strontu próbek gipsu, a zwłaszcza w przypadku wcześniejszego nawilżania ich siarczanem potasu, wzrasta wytrzymałość beleczek z gipsu i zwiększa się współczynnik rozmiękania. Natomiast chlorek baru nie wywiera wpływu na właściwości próbek gipsowych. Oba jony tworzą w próbkach gipsowych siarczany: baryt i celestyn. Nawilżanie beleczek gipsowych roztworem wodnym K2SO4 powoduje powstawanie syngenitu, który lokuje się głównie w warstwie powierzchniowej próbek.

EN

The influence of barium and strontium chlorides on the strength of hardened gypsum paste was examined. The moistening of gypsum bars with barium and strontium water solution, and particularly in the case of earlier moistening them with potassium sulphate solution, the strength of gypsum elements and softening factor are increased. However, barium chloride has no influence on gypsum samples properties. Both ions form sulphates in gypsum samples; barite and celestine. Moistening of gypsum bars with water solution of K2SO4 causes the formation of syngenite, which is located principally in the surface layer of the samples.

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The distribution of traces during the crystallization of barium chloride

Korolewicz T., Wójcik J.

Polish Journal of Applied Chemistry

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2000

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Vol. 44, nr 2-3

159-166

EN

The paper deals with investigations on the distribution of trace amounts of sodium, potassium, calcium and strontium ions in the course of the fractionated precipitation of barium ions from a solution of barium chloride by means of hydrochloric acid. The effects of this operation were determined by making use of the method of radioactive traces applying isotopes of( 24)Na, (42)K, 45Ca and 85Sr. The percentage of trace elements co-precipitated with the sediment of barium chloride is only slight. After the precipitation of about 70% of the matrix, within the investigated range of concentrations of the traces 1 x 10(-4)-1 x 10(-3) % recalculated into solid BaCl(2), there are 99% of the initial amount of sodium, 95-98% potassium, 95-99.5% calcium, 94-96% strontium. Investigated was also the distribution of Cd(II), Co(II), Cu(II), Fe(III), Mn(II), Ni(II), Pb(II), T1(I) and Zn(II) in the course of a single separation of BaCl2 by means of hydrochloric acid. The trace amounts of heavy metals were analysed by means of the AAS-method. After the precipitation of about 70% of the matrix, within the investigated range of concentrations of the traces 5xlO(-5)-5x1O(-3) % most of the trace elements are contained in the solution. Only lead ions co-precipitate in such conditions with the sediment of barium chloride. The obtained results have made it possible to apply the operation described above as one of the stages of purification in the course of winning and analysing spectrally pure BaCl(2).