TOTAL AND SOLUBLE ALUMINUM CONCENTRATION AND SUSPENDED PARTICLES SIZE DISTRIBUTIONS IMPACTED BY SULFATE AFTER THE N aOH NEUTRALIZATION OF Al-BEARIN G ACID MINE DRAINAGE

摘要

A laboratory study was conducted to evaluate the effect of sulfate on effluent Al concentrations in Al-bearing AMD treatment by NaOH. The experimental results showed that sulfate influenced discharge soluble and suspended Al concentrations. Particle size distributions after settling showed that the diameters of suspended particles decreased with increasing sulfate concentration. The reduced particle size yields a relative higher suspended Al concentration. This research found that despite the soluble Al concentration being reduced by sulfate, the presence of sulfate can actually increase the total effluent Al concentration due to the formation of small non-settleable Al containing particles.