Emission of Gaseous Pollutants During Combustion and Co-Combustion of Thermally Treated Municipal Solid Waste

This study shows the results of the combustion of raw and torrefied municipal solid waste. The pellets made of waste were torrefied using a rotary kiln reactor. The average solid yield was 551 g/h. The ratio of solid product mass to the raw material mass (i.e., percentage solid yield, wt%) was 78%. The combustion of the waste/coal mixtures and the torrefied waste was stable, without major problems. The unstable combustion was observed during the combustion of single waste. It was probably caused by the blocking of the portion of raw pellets in the screw feeder. A significantly lower emission of SO2 (i.e., 43–114 mg/m3 STP ref. to 6 v.% O2) was observed during the single combustion of torrefied and raw waste. Significantly higher emissions of CO and H-C were observed during the combustion of single raw and torrefied waste. This higher emission should be reduced by the optimization of air distribution.