Sulphate removal from acid rock drainage using steel slag

Abstract:

The removal of sulphates from acid rock drainage (ARD) using basic oxygen furnace (BOF) slag was investigated. The results indicated that sulphates removal using BOF- slag increased with temperature increase (25-45oC), time (0-24 h) and solid loading (2-12 g BOF-slag/50 ml ARD). The maximum sulphate removal was 65% when 12 g BOF-slag/100 ml ARD was used at 45oC and 24 h residence time. Adsorption followed the Langmuir isotherm with maximum adsorption capacities at 25, 35 and 45oC of 1.949, 1.967, 4.078 mg/g respectively and RL values less than 0.3, indicating adsorption was thermodynamically favourable. The adsorption kinetics followed the pseudo second order kinetics.