Cooling of the sludge is required to obtain the correct viscosity, and auxiliary fuel is required if the water content of the sludge is too low to support combustion on sludge alone.

Heating of the sludge is required to obtain the correct viscosity, and auxiliary fuel is required if the water content of the sludge is too high to support combustion on sludge alone.

Cooling of the sludge is required to obtain the correct viscosity, and auxiliary fuel is required if the water content of the sludge is too high to support combustion on sludge alone.

Heating of the sludge is required to obtain the correct viscosity, and auxiliary fuel is required if the water content of the sludge is too low to support combustion on sludge alone.