인상흑연과 석탄의 품위향상을 위한 부유선별 연구

Abstract

국내 흑연은 국제 경쟁력을 갖지 못하여 현재는 일부 광산에서만 채광하고 있으며, 국내 석탄은 환경 친화적이지 않다는 부정적 인식의 확대로 인해 석탄의 이용도가 갈수록 저하되고 있는 실정이다. 따라서, 본 연구에서는 탄소로 구성된 인상흑연(고정탄소 85.79%)과 석탄(고정탄소 20.68%)을 대상으로 고품위 가능성 확인 및 Clean Coal Technology 기술의 전처리 과정으로서 Ash의 탈회를 위한 목적으로 광물학적, 물리화학적 및 단체분리 특성을 확인하고, 기포제, 포수제, 억제제 종류 및 첨가량 변화 등 부선 조건에 따른 실험을 수행하기 위해서 일반부선과 미립자의 처리에 알맞은 Microbubble column 부선을 실시하였다. 일반 부선의 결과 인상흑연의 포수제의 첨가에 따른 부선효율이 크지 않음을 알 수 있었으며 석탄의 경우 pulp density 20%, collector DMU 101 + Dodecyl amine ( 100mL/ton), frother Pine oil(200mL/ton), depressant(1kg/ton)을 사용하여 Ash 제거율 55.61%, 회수율 85.28%의 결과를 얻었다. Microbubble column 부선의 결과 인상흑연은 pulp density 10%, grinding time 20min., collectorless, frother Pine oil(10.8L/ton), depressant(7.5kg/ton), Wash water 820mL/min., Air flow rate 960mL/min.의 조건에서 Fixed carbon 97.08%, 회수율 98.72%를 얻었으며, 석탄의 경우 pulp density 10%, grinding time 5min., collector DMU101+D.D.A(100mL/ton), frother Pine oil(28.8L/ton), depressant S.M.P(3kg/ton), Wash water 450mL/min., Air flow rate 1197mL/min.의 조건에서 Ash 제거율 66.42%, 회수율 73.12%의 결과를 얻었다.|Currently domestic graphite are excavated only in some mines due to the lack of international competitiveness. The use of coal is decreasing as increasing negative perception of domestic coal not being eco-friendly. Therefore, in this study the possibility of high quality materials of carbon based crystalline graphite (fixed carbon 85.79%) and coal (fixed carbon 20.68%) was confirmed. Also, the mineralogical, physical/chemical and liberation characteristics was found with the aim of decrease in ash amount, during the pre-processing of clean coal technology. In this study, batch flotation and micro-bubble column flotation that was appropriate for the processing of fine particles was used with the variation in kinds and quantity of frother, collector and depressant. As a result of batch flotation, it was found that adding collector to the process, didn't show high efficiency of crystalline graphite flotation. In coal's case, using pulp density 20 %, collector DMU 101 + dodecyl amine (100 mL/ton), frother pine oil (200 mL/ton), depressant sodium silicate (1 kg/ton), obtained the result of ash removal 55.61 % and recovery 85.28 %. In result of micro-bubble column flotation, the crystalline graphite with fixed carbon 97.65 % and recovery 99.23 % was obtained under the condition of pulp density 10 %, grinding time 20min., without collector, frother pine oil (32.4 L/ton), depressant sodium silicate (7.5 kg/ton), wash water 820 mL/min. and air flow rate 960 mL/min. In coal's case, the result was ash removal 66.42 % and recovery 73.12 % under the condition of pulp density 10 %, grinding time 5min., collector DMU101 + D.D.A (100 mL/ton), frother pine oil (28.8 L/ton), depressant S.M.P (3 kg/ton), wash water 450 mL/min. and air flow rate 1197 mL/min.