Abstract
In Japan, the yearly production of sewage sludge amounted to 1.50 million tons in 1992 and about eighty percent of the sludge produced has been treated by landfill disposal.
Studies of effective utilization and recovery of sewage sludge have become important and urgent problems as a necessary consequence of limited landfill sites.
We developed the new production method for high adsorptive activated charcoal from organic sludge containing sewage and food industrial waste water treatment, etc.
The dried sludge was carbonized for 2 hours at 650°C under wrapping vessels with aluminium foil without nitrogen gas flow. The carbonized substances were heated for 10 min. at 650°C with potasium hydroxide flake and washed with hot water. The activated ones were treated for 30 min. at 100°C with 35% hydrochloric acid and then the high adsorptive activated charcoal was produced. The characteristic values of this activated charcoal were as follows: methylene blue number was 160 -250 ml/g; specific surface area was 793-1, 771 m2/g. The developed charcoal can be utilized for the advanced waste water treatment and/or environmental purification such as deodorization and decolorization.
