Reducing sulphur in thermal power plant emission - by returning partial fume flow for admixture with combustion air

摘要

To reduce sulphur emission from a thermal power station, operated e.g. with powdered coal and whose boiler point plant is supplied with pre-heated air and/or to increase plant efficiency, a controlled fraction of the discharging combustion fume flow is extracted by a blower and fed into the combustion air stream. Cold air is supplied as primary and secondary air streams, and the leaked fumes are introduced into the secondary air surrounding an internal flow of prim air at higher pressure. The regenerative type of air preheater has a stationary chamber coupled with rotary inlet and outlet conduits for the alternately supplied gas and air. A suction fan has a series of seals including throat seals. USE - Suitable for incorporating in old plant to bring emitted sulphur down to the locally required 15% or less.