Study of coal beneficiation and trace elements in the Khushuut deposit

Coal beneficiation defines the usage of its organic and non-organic parts. Clean coalscan be used as high-quality fuel, raw material for coke production. Clean coal in the market contains 6-8% of ashes, 1% of sulphur.Thus, beneficiation process depends on the ash content of coal. It is not beneficiated with 7-10% of ash content, partly beneficiated with10-12%, completely beneficiated with over 12% of it. When coal is directly used as fuel, minerals trace elements, gas, dust, and ashescause environmental pollution. Therefore, it is necessary to conduct experiments to research the beneficiation of coal, to determine traceelements during beneficiation factions. In the Khushuut deposit coal belongs to stone coals by standards for classification of coal inRussia. The Khushuut coal has 14.31% of ash content, 0.81% of moisture, 14.76% of volatile matters. It produces 35.91 MJ/kg of heat.The total sulphur content of this coal is 0.25%. Coal beneficiation quality in the Khushuut deposit is 7.51% as determined by the analyticmethod. Thus, the coal belongs to the 2nd category by beneficiation medium quality. According to the study when the coal densityline is 1.25 g/cm3, 69.5% product is possible, with the ash content of 5.95%. The trace elements form depends on the changes of organicmatters, trace elements content, and special features of trace elements cumulation. Trace elements in coal can exist both in organic andmineral parts of it. The following ratio is used to learn these distributions: F = Corg/Cmin, where Corg is the content of trace elements in alight faction (specific gravity is less than 1.6 g/cm). Cmin is the content of trace elements in a heavy faction (specific gravity is more than1.6 g/cm). If F-distribution coefficient is more than one, trace elements are more distributed to the organic parts of coal, if less than one,they are distributed to the mineral parts. Brown coal distribution coefficient is counted by the following sequence: Ge > W > Be > Nb >Ga > 1 > Mo > Sc > >Y > La > Zn > Pb > Se > Rb. The trace elements in coal hazardous to environment and technology are Be, Cd, Co,Pb, Cu, Cr, N, I, Zn, As. F with distribution coefficients (F) of 2.48; 0.13; 0.71; 0.59; 0.61; 0.33; 1.59; 0.69; 1.13 accordingly. Hence,Be, Co, Ni elements in coal are associated with the organic matter, Pb, Cu, Cr, Zn elements are associated with the mineral matter ofcoal. Those elements distribution coefficient is placed in the following upward sequence: Pb < Cu < Zn < Cr < < As < 1 < Ni < Co < Be.

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