FULL-SCALE APPLICATION OF MANUFACTURING BRICKS FROM SEWAGE

Brick making from 100 percent of incinerated sewage sludge ash is deve loped. There are already 8 full scale plants in Japan. All of them emp loy high pressure molding of incinerated sewage sludge ash and firing at about 1000 degrees C. The end products are widely accepted for publ ic works such as flooring of plazas or pedestrian walk ways. Early in the history of the development, overall quality of the sewage brick wa s not competitive. They were subject to get moss growth on the surface because of its high moisture content, or whitening because of leachin g of Calcium Carbonate. The problems were solved by increasing the tem perature of the firing process and by chemical coating. The manufactur ing cost of one sewage brick is around two dollars and the retail pric e is one dollar. (C) 1997 IAWQ. Published by Elsevier Science Ltd.