Emergency shutdown system for a hazardous waste incinerator

Abstract

A system for the controlled safe shutdown of a hazardous waste incinerator upon loss of power. The system includes a primary combustion chamber and a secondary combustion chamber, a gas treatment system, and two standby power sources. One standby power source is available immediately for elements that cannot be shut down even for a second. The other standby power source is a heavy duty generator that takes a short time to get up to speed but is used to power elements that can be allowed to coast for a short time without causing damage to the equipment or the environment. The system includes an uninterruptable power source connected to continue supplying heat and air to the secondary combustion chamber and prevent opening an emergency vent stack cap and thereby prevent the unwanted discharge of gas from the system. At the same time that power is lost, a standby generator is activated to power other elements of the system such as the heavy duty fan that draws the gas through the combustion chambers, spray dryer reactor and filters. The standby generator is needed because the much heavier loads it powers could not be accommodated by the battery based uninterruptable power supply, and the fact that there can be a slight delay between loss of power and operation by the generator without damage to the system or the environment.