As an alternative to recovery, hydrocarbon vapors may be destroyed in a flare, combustor or a thermal oxidizer. For many applications, a device known as a combustor can be successfully used as a safe and economical method of controlling vapors from the handling, storage, or loading of volatile liquid hydrocarbons or ethanol when recovery of the vapors is not a viable option.

Basic Operation

The vapor mixture flows into the vapor collection system at the loading facility and through the vapor header that connects the loading facility with the VCU. The vapor mixture then flows through an in-line detonation arrestor that is equipped with a temperature switch on one face of the detonation arrestor element.
As the vapor mixture flow continues, the pressure will increase in the vapor piping. This increase in pressure is sensed by pressure controls located at the VCU. When the pressure reaches a predetermined level, the vapor-staging valve will open automatically allowing the vapor mixture to flow to the burner elements where the combustible vapors are ignited by the pilot and burned. The assist-air blower is provided to furnish some of the air required for combustion and to provide mixing of combustion air with the vapor mixture. This ensures that the combustion remains smokeless.
The temperature management system, if selected, controls the temperature within the combustion stack by controlling the amount of air that flows into the combustion zone, while also controlling the amount of supplemental fuel gas that is injected into the combustion zone. The temperature is managed automatically during operation by controlling the position of the adjustable air dampers and the assist gas flow. Finally, when the transfer operation is completed, the VCU will automatically turn off the assist air blower and pilot, and then await an automatic re-start when more loading is about to begin.