부유선별법에 의한 국내산 석탄의 품위향상 연구

Abstract

Study for improving Grade of Domestic Coal by Flotation

By Kim, Min Gyu Adv. Prof. : Han, Oh Hyung Dept. of Energy Resource Engineering Graduate School, Chosun University

In order to recover clean coal and reduce the ash content in low-grade coal, flotation experiments were carried out. Three kinds of coal samples were collected from domestic coal mine sites, and were measured according to particle size distribution analysis and an industrial analysis as a preliminary step. These coal samples were also investigated using XRD, SEM, contact angle and Zeta potential. As a result of the XRD analysis, muscovite, pyrophyllite, quartz, graphite, and birnessite were identified in the coal samples, and it is confirmed that the Si and Al can not be liberated from the coal samples according to SEM analysis. To identify the optimum conditions for conditioning reagents(collector, frother, depressant), a general flotation experiment was carried out. The obtained conditions from the general flotation experiment were again applied in the CPT(Canadian process Technologies) column and in a MicrocelTM column flotation test. According to the results from the flotation test, the ash rejection and combustible recovery were enhanced to 81.23% and 84.90%, respectively. The results of the flotation tests showed that the best enhancement rate parameters were when the pulp density was 3.0%, the collector content was 200mL/ton(DMU 101), frother content was 30L/ton(MIBC), the depressant content was 3.0 kg/ton(SMP) and the air flow rate was 1,200mL/min. It is suggest that the results of the flotation experiment conditions was to enhance the utilization of low-grade domestic coal and to up grade the coal quality, and finally to reduced air pollution.