Lime enhanced pressure filtration of iron and steel making sludge

摘要

A method is provided for improving the filtration rate of nonhazardous wastewater streams generated at a steel plant. The solids are concentrated in the wastewater stream. No more than about 5% by weight of lime is added to the concentrated wastewater stream which is then dewatered. A friable filter cake is produced by allowing the solids to harden. The lime addition results in a significant increase in the rate at which the stream may be filtered.