Flue gas Flue gas Flue gas is the gas exiting to the atmosphere via a flue, which is a pipe or channel for conveying exhaust gases from a fireplace, oven, furnace, boiler or steam generator. Quite often, the flue gas refers to the combustion exhaust gas produced at power plants. Its composition depends on what is being burned, but it will usually consist of mostly nitrogen (typically more than two-thirds) derived from the combustion of air, carbon dioxide (), and water vapor as well as excess oxygen (also derived from the combustion air). It further contains a small percentage of a number
Inerting (gas) of liquid is drawn from a tank, a similar volume of air will enter the tank's headspace, potentially creating an ignitable atmosphere. The inerting systems use an inert gas generator to supply inert make-up gas instead of air. This procedure is often referred to as "inerting". Technically, the procedure ensures that the atmosphere in the tank's headspace remains unignitable. The gas mixture in the headspace is not "inert" per se, it's just unignitable. Because of its content of flammable vapors, it will burn if mixed with air. Only if enough inert gas is supplied as part of a "purge-out-of-service" procedure,