Mineral transformation and emission behaviors of Cd, Cr, Ni, Pb and Zn during the co-combustion of dried waste activated sludge and lignite

Co-combustion of dried waste activated sludge (WAS) and lignite was conducted in a horizontal tube furnace system. The mineral transformation and emission behaviors of Cd, Cr, Ni, Pb, and Zn during combustion were examined. The above heavy metals (HMs) were selected because they are more abundant in WAS than in lignite. In the combustion condition of 1000 °C–21% O2–30 min, the minerals in lignite ash were mainly anorthite (CaAl2Si2O8), quartz...