The control of exhaust temperature on a solid waste/sludge incinerator is critical. How this temperature is normally controlled?

Correct Answer: Option D — The exhaust temperature is controlled by regulating the admission of relatively cool ambient air into the exhaust stream.

Incinerator exhaust temperatures must be strictly managed to protect the refractory lining and prevent damage to the stack. Introducing ambient air, known as dilution air, effectively cools the flue gases before they exit the combustion chamber, ensuring the system operates within safe thermal limits as specified by the manufacturer.