Manufacture of Adsorbent from Fly-ash and Anthracite

비산회재 및 무연탄을 원료로 한 흡착제 제조

The utilization of fly-ash containing high levels of the unburned carbon was investigated. In this study adsorbents were manufactured from fly-ash ad a raw material and the manufactured adsorbents were applied to the waste-water treatment including heavy metals. Varying the anthracite(Jangsung coal) content, three types of pellet were made. The carbon content of pellet increased appreciably upon the addition of anthracite. After carbonization and activation using the pellets, adsorbents showed following characteristics; the range of hardness was between 85% and 96%, iodine number was from 100 mg/g to 300 mg/g. In proportion to the anthracite addition, hardness and iodine number increased. Through the adsorption experiments of heavy metals, removal efficiencies of Pb and Cr by manufactured adsorbents were over 90%. In case of fly-ash, removal efficiencies of Pb and Cr were 31.5% and 5.6% respectively. The reason why removal capacities of manufactured adsorbents were higher than fly-ash was postulated that adsorption capability was improved by unburned carbon and $SiO_2$ which included in fly-ash during steam activation.

본 연구는 현재 폐기되고 있는 미연탄소분을 많이 함유한 비산회재를 이용하여 흡착제를 제조하고자 하였으며, 제조된 흡착제에 대한 중금속 제거 실험을 통하여 중금속을 함유한 폐수처리기의 적용가능성을 알아보았다. 비산회재에 장성탄의 혼합비율을 달리하여 세 종류의 펠릿을 제조하였으며, 장성탄의 혼합비율이 증가함에 따라 펠릿의 고정탄소함유량이 증가하였다. 이를 이용하여 탄화와 활성화를 거처 85~96%의 경도와 100~300 mg/g의 요오드 흡착량을 갖는 흡착제를 제조하였으며, 장성탄 혼합비율이 증가할수록 경도 및 요오드 흡착량이 증가함을 알 수 있었다. 중금속의 제거실험에서 제조된 흡착제에 대한 Pb와 Cr의 제거율이 90% 이상을 나타내었으며, 비산회재의 겨우 Pb 31.5%, Cr 5.6%의 낮은 제거율을 보였다. 이는 활성과정동안 비산회재에 함유된 미연탄소분과 $SiO_2$에 의하여 흡착성능이 증가되었기 때문이다.