ENHANCEMENT OF DREDGED MATERIALS DRYING SPEED BY INCORPORATION OF IN-SITU DRIED SLUDGE

摘要

Accelerating the drying speed of dredged sludge from Lake Kasumigaura in Japan, is one of the important issues to make progress in the measures for its water purification. How to improve the moisture permeability to enhance the drying speed of dredged sludge on the disposal yards was investigated. With ten small pots placed in a plastic greenhouse, dried clods of dredged sludge were incorporated into the original dredged sludge (around 450% d. b. moisture content) at 100% and 200% incorporation ratio with four levels of clod diameter, and their daily mass losses were measured during 7 weeks. Sand materials were also incorporated at two levels of incorporation ratio. All the treated sludge materials showed high moisture losses compared to non-treated sludge material for the first four weeks. The facts give a prospect that mixing the in-situ top dried sludge with the bottom soaked sludge might get enhanced the drying speed of dredged sludge.