|About this Abstract
||Part C-1: Hydrometallurgy 2018
||The Dewatering Behaviour Of Transformed Ferri-oxyhydroxide Precipitates Formed Under Moderate Temperature And Varying Fe(III) Concentrations
||Cledwyn Mangunda, Jochen Petersen, Alison Lewis
|On-Site Speaker (Planned)
Mining operations generate Acid Rock Drainage (ARD) that poses a significant threat to the natural environment. ARD treatment using Ca(OH)2 leads to the precipitation of a sludge dominated by FeOOH. This sludge has poor dewatering tendencies and is deposited in landfills with potential for metal remobilization. This study investigated the dewatering behaviour of a precipitate formed during elevated temperature treatment of a primary, pre-settled sludge from the neutralisation of aqueous acidic Fe2(SO4)3 and Ca(OH)2 solutions in an MSMPR reactor.
The resulting treated precipitates were analysed for micro-properties, with results showing that an increase in the secondary reactor temperature from 25ēC up to 50ēC led to an increase in mean particle size, a decrease in the number of particles and improved dewatering behaviour. This was ascribed to the attainment of a circumneutral pH, surface charge decrease which favoured agglomeration and a change in micro-structure that allowed for better water passage.
||Planned: At-meeting proceedings