Flue-gas condensation
Flue gas condensation is a process, where flue gas is cooled below its water dew point and the heat released by the resulting condensation of water is recovered as low temperature heat.Cooling of the flue gas can be performed either directly with a heat exchanger or indirectly via a condensing scrubber.Acid condensation can result in low-temperature corrosion, which can threaten the safety of plant.The heat recovery potential of flue gas condensation is highest for fuels with a high moisture content (e.g. biomass and municipal waste), and where heat is useful at the lowest possible temperatures.Thus flue gas condensation is normally implemented at biomass fired boilers and waste incinerators connected district heating grids with relatively low return temperatures (below approximately 55 °C (131 °F)).