- Duct Burners
Linear and in-duct burners were used for many years to heat air in drying operations before their general use in cogeneration systems. Some of the earliest systems premixed fuel and air in an often-complicated conguration that red into a recirculating process airstream. The rst use was in high-temperature, depleted oxygen streams downstream of gas turbines, in the early 1960s, to provide additional steam for process use in industrial applications and for electrical peaking plants operating steam turbines. As gas turbines have become larger and more efcient, duct burner supplemental heat input has increased correspondingly.