The technological inspection of the electrolyte composition in aluminum production is performed using calibration X-ray quantitative phase analysis (QPA). For this purpose, the use of QPA by the Rietveld method, which does not require the creation of multiphase reference samples and is able to take into account the actual structure of the phases in the samples, could be promising. However, its limitations are in its low automation and in the problem of setting the correct initial values of profile and structural parameters. A possible solution to this problem is the application of the genetic algorithm we proposed earlier for finding suitable initial parameter values individually for each sample. However, the genetic algorithm also needs tuning. A self-configuring genetic algorithm that does not require tuning and provides a fully automatic analysis of the electrolyte composition by the Rietveld method was proposed, and successful testing results were presented.
Separation of graphite particles from impurities while preserving the graphite’s flaky structure during processing is an essential challenge in graphite beneficiation. Thermal grinding of cryptocrystalline graphite, as proposed by A. D. Dmitriev, is a promising approach to address this challenge. This research was aimed to identify the optimal thermal grinding parameters for graphite that maximize the separation of cryptocrystalline graphite particles from impurity minerals without compromising the graphite’s flaky morphology. Graphite ore samples from the Kureiskoye deposit with a particle size fraction of –20+15 mm were used for this research. The optimal thermal grinding conditions selected for the work included maintaining the graphite temperature at 800–850 °C for 20 minutes, with an initial graphite moisture content of 5 %. Thermally ground graphite with a particle size of –0.2+0.16 mm, exhibiting a carbon content of 91–95 % and a crystallinity degree of 39.5 %, has been identified as the most promising fraction for new products. The isolated fraction of thermally ground graphite meets the specifications for graphite grade GT-2 under GOST 17022–81, with an ash content not exceeding 8.2 %, moisture content of 0.58 %, sulfur content of 0.06 %, iron content of 0.78 %, and no detectable volatile substances. The yield of the –0.2+0.16 mm fraction is approximately 10 %, with 20–30 % consisting of barren ore that can be effectively utilized as a filler in concrete mixes, while the remaining graphite can be used in metallurgical applications. Successful separation of the flaky component from cryptocrystalline graphite through thermal grinding significantly broadens the range of thermally ground graphite-based products, including the production of crucibles for melting metals and alloys.
1 June 2018 in Journal of Siberian Federal University. Chemistry
RTReshetnev Siberian State University of Science and Technology
Reshetnev Siberian State University of Science and Technology
SSSamoilo Alexandr S.
Samoilo Alexandr S.
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Сибирский федеральный университет (СФУ) входит в топ-15 вузов России. Ведущие научные школы Красноярска. Лучший в России кампус. Мировые индустриальные партнёры