Fe-Al recovery from mine water treatment residuals and product testing for wastewater treatment - phosphate and turbidity removal

Mine water treatment scope is to produce an effluent which satisfies the discharge limits according to permits. However, the production of metal-rich sludge is a consequence of the mine water treatment and its disposal as a waste raises the cost of the whole operation, so ways to convert the sludge into marketable products are desirable. For example, mine water treatment sludge can be used for adsorbents or pigments production or some of the sludge components can be extracted and utilized as coagulants. Coagulants were obtained from mine water after partial precipitation of metal species or after conventional treatment, by leaching the sludge with acid. The effectiveness of coagulants considering phosphate, chemical oxygen demand and turbidity is presented in this paper, alongside with some of the drawbacks as observed.