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Celestite upgrading by jigs in presence of steel balls as ragging material

Sobhy Ahmed, El-Midany Ayman A., Ibrahim Susan S.

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 5

118--128

EN

Gravity separation using jigs is widely used for coarse particle sizes separation. However, fine sizes reduce jig performance. In this study, the upgrading of celestite ore by jig was investigated at different size fractions in the presence of ragging material. Three size fractions, i.e., -15+2 mm, - 2.0 + 0.50 mm and - 0.50 + 0.08 mm were used. The steel balls were used, as ragging material, to improve the separation of fines as well as to improve the concentrate quality. The statistical design was used to correlate celestite grade and recovery with studied operating variables, i.e., the ragging number of layers, ragging balls diameter, and separation time, at a fixed water flow rate and stroke length. The design results indicated that the ragging balls diameter and their number of layers play an important role. The smaller the ragging balls diameter and the higher the ragging number of layers are the better the concentrate grade but the longer the separation time. A celestite concentrate of (> 95% SrSO4) with 74.5% recovery was obtained for - 2.0 + 0.50 mm size fraction at the optimum conditions; i.e., 3.1 mm ragging balls diameter, one ragging layers, and 15 minutes separation time.

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Mechano-chemical conversion of celestite in highly concentrated sodium carbonate media

Sezer Raşit, Arslan Cüneyt

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 2

324--335

EN

An effect of high-energy ball milling on the mechano-chemical conversion of celestite to strontium carbonate (SrCO3) was studied. A celestite ore was ground by a planetary ball mill in a highly concentrated sodium carbonate (Na2CO3) solution. The experimental study was carried out to determine the effects of milling time (15, 30, and 45 min) and Na2CO3 concentration (1, 1.25, and 1.5 M) on the particle size and SrCO3 percentage of the product. A celestite/ball weight ratio was selected as 1/10 and the volume of carbonate solution was calculated for the stoichiometric amount of sulfate in celestite, as constant. After filtering, washing and drying the precipitated SrCO3 sludge was analyzed by XRD, SEM-EDS. Powders were leached in HCl solution and analyzed by AAS in order to determine the SrCO3 amount in the product. A response surface methodology was applied via the Box-Behnken method for the results of particle size and SrCO3 percentage. Regression model coefficients were 98.61 and 98.14%, which were the results of compatibility as experimentally obtained and predicted by the model, respectively. The maximum amount of SrCO3, 96.84% and the minimum particle size, 10.297 μm were obtained with the maximum values of the parameters, 45 min, 1.5 M Na2CO3, and 450 rpm.

3

Celestite in the weathering crust on limestone exposed to an urban atmosphere in Cracow (Poland)

Wilczyńska-Michalik Wanda, Michalik Marek

Mineralogia

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2006

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Vol. 37, iss. 2

133--142

EN

Celestite containing very low amounts of barium occurs in weathering reaction zones developed on the Pińczów limestone exposed to the polluted atmosphere of Cracow. The mineral occurs both in limestone pore spaces filled with gypsum and in black gypsum crust. The Pińczów limestone contains ca 500 ppm strontium which was released during the reaction with atmospheric pollutants. The nucleation and growth of celestite, requiring significant concentration of components in evaporating solutions, is associated with gypsum crystallization.

PL

Celestyn z niewielką zawartością baru występuje w strefach reakcji rozwiniętych na wapieniu pińczowskim wystawionym na działanie zanieczyszczonej atmosfery w Krakowie. Minerał ten występuje zarówno w porach wypełnionych gipsem, jak i w czarnych naskorupieniach gipsowych. Wapień pińczowski zawiera około 500 ppm strontu, który jest uwalniany podczas reakcji z zanieczyszczeniami atmosfery. Zarodkowanie i wzrost celestynu wymagające znacznej koncentracji składników podczas parowania roztworów są związane z krystalizacją gipsu.