Xie Guangyuan

Experimental study on improving the separation performance of liquid-solid fluidized bed using flotation reagent and newly designed aeration unit

ABSTRACT In the study, a pilot-scale liquid-solid fluidized bed (LSFB) apparatus was modified by adding an aeration unit, which enabled us to test the effect of air addition on LSFB separation performance for fine coal (0.25 ~ 1.00 mm). Upward water flow velocity, aeration volume and flotation reagent (Kerosene and 2-Caprylic alcohol) dosage varied throughout the experiment. The optimum results from the three experimental conditions (without aeration, with aeration only, with aeration and reagent) were compared by their respective probable error (Ep) values. The Ep values of the three experimental conditions were 0.109, 0.08 and 0.07, respectively. The results indicated that the addition of air obviously enhanced LSFB performance, while the addition of flotation reagent further improved the separation result.

Removal of organic carbon in coal-series kaolin using gravity separation

ABSTRACT Coal-series kaolin, a precious associated nonmetal mineral in coal mines, shows high industrial value. However, it usually contains organic carbon and a small amount of impurities including iron and titanium elements, which seriously decrease the whiteness of final kaolin products. In this investigation, gravity separation method was adopted to remove organic carbon from coal-series kaolin (decarbonized kaolin) based on the differences in density. It was found that compared with the raw kaolin, the loss on ignition (LOI) of decarbonized kaolin was decreased by 44.22%, and the contents of Fe2O3 and TiO2 were also decreased by 48.57% and 59.57%, respectively. The decarbonized kaolin was of high purity, and the whiteness of the decarbonized kaolin was much higher than that of the raw kaolin. The organic carbon separated from the coal-series kaolin can also be used in various ways depending on its coal rank and quality, which avoids the waste of coal resources. The coal-series kaolin can obtain a better use after removing the organic carbon using the gravity separation.