This report assessed the current state-of-the-art of antimony removal technology for mining industry wastewaters. Through literature review and personal interviews, it was found that most mines and mills reporting significant quantities of antimony in their raw wastewater had approximately 0.1 to 0.2 mg/l antimony remaining after tailings pond settling. This reduction in antimony content without any chemical treatment indicates that for most mines and mills the antimony-containing wastewater components are in the form of suspended solids and may be easily removed. Sulfide precipitation technology cannot remove soluble antimony to levels below 2.0 to 3.0 mg/l and lime precipitation cannot lower levels below 1.0 mg/l. A minimum desired level of 0.5 mg/l of antimony was selected for this technology assessment based on the effluent limitation recommended by the EPA BPCTCA in antimony mines. There is currently no demonstrated technology for achieving this minimum desired antimony level. Ion exchange and insoluble starch xanthate appear to be promising technologies for antimony removal; carbon adsorption, sodium borohydride reduction, and peat moss adsorption do not appear feasible.

Contract no. 68-03-2566. Includes bibliographical references (pages 57-60). Microfiche.