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Feldspar ores occur usually together with quartz, micaceous minerals and some amount of coloured impurities. For fu rther utilization of feldspar is necessary to effectively remove colouring gangue minerals. The main me thod of feldspar ores treatment is froth flotation. In this paper the emphasis is put on efficiency of pH changes and varied dosages of flotation reagents in application of laboratory flotation.

The hydrometallurgical process for obtaini ng alumina by Bayer process bauxite is getting significant amounts of red mud (0.8 - 2 t / t Al 2O3). It is deposited in dumps which can cause danger for environment mainly due to the alkali content ( pH = 8-13) and small dimensisons of particles (less than 60 microns). Chemical and mineralogical composition of red mud bauxite is closely related to type of the bauxite used as raw material and processing conditions determined by some peculiarities of applied technology (pr...

The bauxite is not processed through the usua l processes of ore en richment because of the mineralogical composition and structure, the intergrowths of minerals being very fine. Mineralogical characterization is very important to choose the method of extracting alumina from bauxite. This paper presents the mineralogical st udy of a hydrargyllitic bauxite from Sierra Leone and of the red mud resulted after extraction of alumina by Bayer method. The mineralogical characterization of red mud is needed to choose the ...

Researches of ilmenite reduction kinetics defining intensity of process course are carried out for many years. Main characteri stic is concentrate reducibility degree, characterizing process speed in concrete conditions. Ilmenite reduction process is very complicated, and its speed depends on many factors - oxides nature, temperature and degrees of concentrate grinding. Iron complicates ilmenite concentrate use in its chlorination process for obtaining titanium tetrachloride - an initial product for obtaining of s...

The paper deals with the study on pyrite liber ation from talc raw ma terial. The material comes from deposit nearby Gemerska Poloma village (Eastern Slovakia). A lumpy material was subjected to crushing, grain si ze and float-sink analyses. Heavy and light products were also assayed. XRD study of sel ected products of float-sink analysis was carried out. Thus, it was found that iron and sulphur concentrate in a grain size classes of 0.5-3mm, above all in 1-2mm. The highest mass yield of heavy product was attained...

The biotechnological methods have wide application area in the remediation of heavy metals from the waste waters. This study presents the results of the biological-chemical activation of coal waste from the Cigel deposit (Slovakia) by selected species of microorganisms, as well as: Aspergillus niger, Asperg illus clavatus, Penicillium glabrum and Trichoderma viride . The quantitative maceral composition has been investigated. The complex maceral analysis shoved that microorganisms preferentially disrupt the struct...

The national and international economic crisis has increased the interest in utilizing coal to produce electric or thermic energy, but that means also an increased pollution. According to the U.E. normative, Romani a’s environmental problems with the SO X, NOX, CO, CO 2 emissions from the th ermoelectric plants will be partially solved by 2012. However there will remain some important sources of pollution such as ash and breeze deposits, which have a negative impact upon the microclimate and upon all the environ...