PARTICULATE FORMATION IN POWER-STATION BOILER-FURNACES

The review covers some of the more fundamental aspects of the production of particulate pollutants by fossil-fired power station boilers. The presence of soot is essential for efficient radiant heat transfer in oil-fired and to a lesser extent in p.f. fired boilers, in addition to its potential as a pollutant, thus its formation and burning has been intensively studied. Consequently, the section on soot is the most comprehensive section. Further less detailed sections deal with the nature of inorganic constituents of coals and oils burnt in C.E.G.B. power stations, cleaning of such fuels, ashes produced from the inorganic matter, and novel burning techniques which have recently been attracting extensive attention, for reducing the formation both of gaseous and particulate pollutants. Some interesting aspects of the potential interactions of particulate pollutants with gaseous ones are outlined. For instance, the reactions of compounds of alkali and alkaline earth metal in the form of fumes with oxides of sulphur, leading to the trapping of oxides of sulphur in deposits within the boiler is discussed. In addition, modification of combustion by recirculating flue gas through the coal mills in order to reduce pollutant formation would help to reduce the hazard of coal dust explosions in the burner feed pipelines. © 1979.