Characterization of Malaysian domestic sewage sludge for conversion into fuels for energy recovery plants

Sewage sludge is one of the largest contributors of waste material in Malaysia, and it indirectly elevates local environmental problems. The use of this waste material as an alternative fuel can be an effective solution, as it not only contributes as an energy source but also solves environmental issues related to sewage sludge disposal. To support the development of a fuel source from sewage sludge, a characterization procedure for its energy content and chemical composition becomes very important. The preliminary findings reported in this paper, for Malaysian domestic wastewater sewage sludge, found the following properties through the respective experiments: a) proximate analysis (moisture content 12%, volatile matter 48.86%, fixed carbon 19.32% and ash content 31.86%), ultimate analysis (Carbon 33.01%, Hydrogen 4.97%, Nitrogen 5.52% and Sulfur 1.18%) and bomb calorimeter (heating value 15.7 MJ/kg). An earlier developed empirical equation for predicting the heating value of domestic sewage sludge was validated with the experimental results from the current work and found to be in good agreement. The heating value of Malaysian sewage sludge can therefore be predicted with reasonable accuracy for the design of various energy conversion systems.