Effect Of High Speed Secondary Air Jets On The Overall Performance Of A Large MSW Incinerator With A Vertical Shaft

Abstract This paper discusses a number of proposed design modifications and changes in operational conditions which have a major influence on the overall performance of the Sheffield municipal solid waste incinerator plant. This 35 MW unit incorporates a heat recovery system for district heating. Four different secondary air injection systems and various primary air distribution patterns along the grate were investigated using computational fluid dynamics in an attempt to eliminate the existing slagging problems and at Ihe same time obtain optimum combustion conditions which would minimise potential emissions of toxic pollutants and reduce maintenance costs at the plant. The modelling work showed that the use of four tangential high speed secondary air jets together with optimising the primary air distribution along the grate, produces substantially longer residence times, improves the temperature profile at the exit, reduces the concentration of toxic pollutants and increases the combustion efficiency of...