Use of Papermaking Sludge as New Material

Recent efforts to actively recycle paper have caused the amount of papermaking sludge to increase steadily each year, with current estimates of over 3,000,000 tons discharged annually throughout Japan. The Nippon Telegraph and Telephone Corporation has achieved success in converting ash derived from incinerated papermaking sludge into a new porous material with high cation exchange capacity by reacting this ash in an alkali solution. This paper reports some application of the new material to environmental conservation, such as improvement of water quality and admixture in concrete.