First Municipality Orders System for Producing Activated Carbon from Sewage Sludge

Sep. 05, 2007

Tokyo, September 5, 2007 – Kawasaki Plant Systems, Ltd. announced today that it has received an order for a sewage sludge processing system from Tainai City, Niigata Prefecture. The system is capable of producing activated carbon from sewage sludge and will be installed in the city’s Nakajo Water Treatment Center. It will be the first system used by a local government and is scheduled for completion in March 2008.

The sewage sludge processing system dries, carbonizes and activates* sludge to produce activated carbon, which can be used instead of commercially available activated carbon to remove dioxins from incinerator exhaust and contribute toward creating a greener society.

The system is comprised of sludge transport/storage, drying and carbonization systems. Kawasaki is responsible for everything from designing the overall system including machine and electric systems to production, installation and onsite testing.

The system consists of two main components, including a drying system where aggregated sludge is crushed and dried by heated air. Its compact design results in superior thermal efficiency. The other primary component is the carbonization system where the granular sludge is once again dried, thermally decomposed, carbonized and activated as it is carried along the ribbon screw conveyor section of the carbonization conveyor. High temperatures maintained at 800 to 900℃ during the latter half of the carbonization process create fine pores on the charcoal surface, resulting in highly adsorptive activated carbon.

Kawasaki has a proven track record in the Japanese market for sewage sludge drying and incineration equipment and has conducted extensive testing on sludge treatment technologies that convert sludge into activated carbon. Kawasaki’s cost-cutting sludge processing technology for effectively converting sludge into activated carbon was highly evaluated by the Japan Institute of Wastewater Engineering Technology in March 2007. The technology was developed for the LOTUS Project (Lead to Outstanding Technology for Utilization of Sludge Project) under the Ministry of Land, Infrastructure and Transport’s Spirit 21 (Sewage Project, Integrated and Revolutionary Technology for the 21st Century).

*Manufacturing of highly porous charcoal for enhanced adsorption.