Abstract: A waste treatment plant (1) comprises an incinerator unit (30) and an autoclave unit (9) and operates such that steam for the autoclave is generated from heat in the incinerator and contaminated water from the autoclave is used to control the temperature in the incinerator, the contamination being destroyed in the process. Exhaust gas from the incinerator is used to reduce the water content of waste treated in the autoclave. Steam generated by the incinerator is available for plant washing operations, to wash bins that supplied waste to the plant before the bins are returned.