현재 제철소에서 소결공정에서 탈황공정 중 발생되는 제철 탈황분진은 현재 연간 100,000톤 이상으로 추정하고 있으나 80%이상이 재활용되지 못하고 있다. 발전소에서 발생되는 탈황석고는 사업장폐기물로 분류되어 석고보드 등으로 재활용되고 있으나, 제철탈황분진은 중금속 등의 유해성분으로 인하여 지정폐기물로 분류되어 재활용되지 못하고 인근 매립장에서 처리되고 있다. 본 연구는 탈황분진의 안정화를 위하여 지르코늄 유성밀을 사용한 분쇄방법으로 처리한 후 그 특성을 분석하였다. 유성밀로 분쇄후 분석한 결과 입자의 크기는 2.8 ㎛에서 0.5 ㎛의 크기로 작아졌으며, XRF, TGA 분석은 분쇄전과 거의 동일하였다. XRD분석에서는 피크의 강도가 더 작아진 것으로 유해성이 감소된 것으로 판단되며, 폐기물공정시험방법으로 분석한 중금속의 농도는 Cu의 경우 1/6이상 감소하였다.

The results of particulate matters level and heavy metal concentration, which surveyed in Gwang-Yang, Dang-Jin steel industry area, are as follows; The PM2.5, PM10 of exposure area are 22.3μg/m3, 40.4μg/m3 each in Kum-Ho dong, and 28.1μg/m3, 51.5 each in Jung dong. The PM2.5, PM10 of control area are 16.4μg/m3, 29.5μg/m3 each in Bonggang-myeon. The level is higher in exposure area than control area. In case of Dang Jin, the concentration of PM10 and PM2.5 is higher in exposure area than control area (PM2.5-20.4μg/m3, PM10-39.2μg/m3). The Pb level of Dang Jin area is higher in exposure area(0.13μg/m3) than control area(0.1μg/m3), and both Gwang-Yang and Dang-Jin area lower level than the Guideline level of Korea EPA.

In this study, we have investigated leaching characteristics of heavy metals and alkalinity centering around steel mill slags by several extraction methods, for the purpose of risk assessment that exert influence on environment and offer of the foundation data of reuse by slags. Korean standard method, U.S.EPA Extraction Procedure, alkalinity extraction test and 9 step sequential fractionation experiment by Miller et al. were carried out for investigating leachability of steel mill slags. As a result of this experiment, heavy metals were little detected and it was considered that alkalinity does not exert a bad effect around environment in slags with large particle size. By the result of 9 step fractionation experiment, heavy metal contents in slags were not plentiful, in addition, even comparatively plentiful contended heavy metals, for the most part, were likely to detained or bonded in silica matrix. Therefore, in case of slags with large particle size, it seems that leachability of heavy metals were next to impossible that is existed as a safety condition.