Technical Bulletin No. 0014: White Water Research Report: Some Factors Influencing the Dewatering of White Water Sludges

The clarification of waste water, commonly termed "white water”, from the manufacture of paper and paperboard results in a voluminous sludge. Eldridge (1) labels the handling and disposal of this sludge one of the major problems connected with the treatment of mill waste. The complexity of this problem is in proportion to the sludge volume. This study was undertaken to determine means by which the sludge might be concentrated. Little has been written regarding the treatment of white water sludge. Eldridge (l) (2) states that the sludge concentrates readily on standing and may be dewatered by pending or vacuum filtration. He indicates that 75% sludge volume reduction can be attained by the former treatment, while the latter will result in a filter cake of 70-75% moisture content. Some sludges, he adds, are difficult to dry on vacuum filters, and a preconditioning chemical, usually lime, is required.