RECOVERY OF COAL SLIME BY USING THE KNELSON CONCENTRATOR

Year 2020, Issue: 045, 215 - 224, 31.12.2020

Ali Uçar , Oktay Şahbaz , Nezahat Ediz , Sevgi Karaca , İsmail Göktay Ediz

Abstract

The coal slimes are formed during the gravity processes applied at the coal preparation plant (Coal Washery). After the washing process of coal, large amounts of fine coals with a high calorific value is being discharged to the abandoned open cast spaces causing economic losses and significant environmental problems. A re-processing of these coal slimes by using the newcomer separation devices, such as Knelson concentrator, is a necessity due to the filling up of ponds, requirements of new legislation, and so on. In this study, the recovery of fine coal slimes of Tuncbilek Washery in Kutahya-Turkey was carried out by using the Knelson Concentrator (KC). Besides, the effect of particles sizes on the recoverability of fine coals was also investigated to reach optimum recovery. According to the particle size analysis made for this purpose, the maximum particle size of the samples was found as 4 mm while the ratio of material below 0.038 mm was found as 69.66%. From the chemical analysis made (ash, calorific value), it was also found that the ash content and the upper calorific value of the waste material 68% and 1603 kcal/kg, respectively. After the coal processing studies carried out using the KC for two different particle size groups, it was realized that the recovery rate was highly reduced at carbon content which is the indicator of the valuable substance while it was slightly decreased at lower particle sizes. When all the coal processing results were considered, it could be concluded that clean coal with 70% carbon content and an upper calorific of 4807,9 kcal/kg could be obtained through a combustible recovery of 57.4%.

Keywords

Coal Recovery, Knelson Concentrator, Slime Pond, Western Lignite Corporation

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