Dewatering of mine drainage sludge

Sludge formed by the neutralization of acid mine drainage is generally affected by the acid mine water composition and the method of neutralization used. The effects of both raw water chemistry and the various treatment processes on sludge composition are enumerated for each treatment process. The methods discussed include: Conventional lime neutralization; Mechanical aeration; Lagoon aeration; pH; and Sludge recirculation. Several other processes, described and studied in slightly more detail, include the High Density Sludge Process, the Densator Process, the Elpo Treatment Process, and the use of magnetic sludge. Methods of thickening, conditioning and dewatering are also presented, with vacuum filtration appearing as the most feasible.