Process for low-pollutant combustion in a power station boiler

摘要

In a process for low-pollutant combustion in a power station boiler (22) for steam generation, at least one precombustion chamber (24) acts at the boiler itself, which precombustion chamber is operated with at least one burner (25a-c). At least a part of the primary air (26) initially flows through a heat exchanger (24c) , in which a caloric treatment of this air takes place to give combustion air (26a). This combustion air (26a) then flows into the burner (25a-c), where a mixing, and subsequent combustion with fuel (12) or with another mixture takes place. A further air stream as secondary air (27) is injected directly into the precombustion chamber (24), this taking place directly before the actual join of the precombustion chamber (24) to the boiler (22). Downstream of the precombustion chamber (24), a tertiary air stream (29) is fed into the boiler (22). Using this configuration, a process with double air staging is proposed, the boiler (22) being operated with air deficiency. As a result of this substoichiometric operation of the boiler (22), nitrogen-containing fuel compounds can be reduced.