Abstract
The traditional methods for the disposal of sewage sludge are landfilling, recycling as fertilisers in agricultural lands, dumping into sea and incineration. In thc recent past, Sludge incineration has been rapidly gaining ground duc to environmental constraints facing the Other methods. However, the cost of pollution control during sewage sludge incineration is currently very high due to the expensive flue gas treatment facility required. Futhermore, large quantity Of ash is produced which is highly contaminated with heavy metals and must be disposed off in special landfilling sites in order to avoid ground water pollution. To reduce the cost Of pollution control, new technologies for thermal treatment of sewage sludge are currently being introduced into the market. These include co-combustion of Sewage sludge in brick works, cement works, municipal solid waste incinerators and coal power plants. Other new processes are wet oxidation, Oil from sludge and fuel from sludge processes as well as gasification, The peculiarities Of these technologies include low emissions of air pollutants, low quantity of flue gas and the production of molten ash in which the heavy metals are firmly bonded. This paper discusses some of these technologies.
Recommended Citation
Ogada, T. (1998). NEW TECHNOLOGIES FOR THERMAL DISPOSAL OF SEWAGE SLUDGE. Tanzania Journal of Engineering and Technology (TJET), 22(2), 186-200. https://doi.org/https://doi.org/10.52339/tjet.v22i2.278
Publisher Name
University of Dar es Salaam