الفهرس 
ARABIC SUMMARY
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Abstract
The flotation kinetics of Maghara coal were studied with the use of a 3000 ml wemco Fagergren cell in a semi-batch mode. The experiments were carried out under different operating conditions (i.e. particle size, collector dosage, pulp density and frother dosage).
The flotation kinetics of Maghara coal can be described by the Rosin-Rammler’s model. The model parameters / which characterize the kinetics of flotation / can be determined from experimental data collected from semi-batch tests, and they also have physical meanings. Effects of the different operating conditions on the model parameters were investigated. In addition, the effect of particle size on the separation efficiency (at different operating conditions) was investigated.
The results obtained showed that, for all size ranges investigated, the flotation rate constant increases with the increase of both the collector dosage, pulp density and frother dosage up to a certain limit, then starts to decrease as the values of these variables increase. The optimum conditions were found to be at collector dosage = 1360 g/t, pulp density = 7.5% and frother dosage = 35.2 mg/L. These optimum conditions were the same for carbonaceous matter and mineral matter.
The results indicated also that, the flotation rate constant of carbonaceous matter and mineral matter increases as the particle size decreases to a certain limiting size range (-160+100 um) below which the flotation rate constant starts to decrease. But the separation efficiency was found to decrease as the particle size decreases until a limiting particle size then starts to increase with decrease in particle size.
The comparison between the calculated (predicted from the model) recoveries and those experimentally determined has shown a good agreement within the size range investigated. Thus, the presented model will give a good insight into the flotation process of Maghara coal.