Due to its high water content, low dewaterability, and rigorous regulations for sludge reuse or disposal, sludge management is one of the most demanding and challenging duties of wastewater treatment plants. One of the most recent goals of wastewater treatment plants has been to develop more ecologically friendly technologies for reducing sludge disposal volume and converting sludge into biofuel. The conversion of sludge into biogas, syngas, and bio-oil, which can then be converted into electricity, mechanical energy, and heat, is a common example of sludge energy recovery.
- Track 1-1 Primary Sludge
- Track 2-2 Secondary Sludge (biological)
- Track 3-3 Secondary Sludge (biological)
- Track 4-4 Mixed Sludge
- Track 5-5 Tertiary Sludge (chemical or physiochemical)