Designing chain grate stoker links to reduce polluting and particulate emissions

Polluting emissions from chain grate stoker furnaces may be attributable to a poor combustion-air distribution to the fuel bed. Previous work showed that a better distribution of air is achieved by modifying the aerodynamic features of the individual grate links. Work described here submits the improved link design to combustion tests in a small-scale pot furnace and a full-scale furnace. Reductions in particle lift-off and gaseous pollutant emission are demonstrated. However, increased air channel gaps in the new link design resulted in larger loss-on-ignition for the particulate material lifted-off and for the ash remaining on the grate.