Basic characteristics of low-temperature carbon products from waste sludge

There is a growing need to recycle resources effectively and therefore it is important to develop technologies for reuse of waste materials, e.g. composting. Although compost offers a good potential, its use is not widespread, as compost technologies are not as yet practical in Japan. We have been proposing carbonization though work in this area is just starting and there is little or no reliable data available. This study was done to investigate the basic properties of carbon products from sludge, and compare them with mainly those of wooden charcoal. The results indicated that carbon products from sludge are more porous and contain some useful minerals such as nitrogen, phosphorus and potassium, etc. and harmful substances exceeding the acceptance level were not observed.