Experimental study on the cracking of tar derived from municipal solid waste gasification to produce syngas

The cracking of real tar obtained from a pilot-scale gasifier of municipal solid waste was studied. The tar was both thermally and catalytically cracked under N₂ atmosphere. Thermal cracking experiment was conducted at 600°C, 700°C, and 800°C, while catalytic cracking experiment using waste wood-derived biochar as catalyst was conducted at 700°C. Biochar was produced by conducting slow pyrolysis of wood in the lab-scale. Thermal cracking of tar at 800°C significantly improved the H₂ yield in the produced gas compared to thermal cracking at 600°C and 700°C. The results indicated a significant improvement upon the application of biochar compared to the thermal method in terms of H₂ yield, tar conversion, and H₂/CO ratio of the produced gas. The H₂ yield from catalytic cracking at 700°C was only slightly lower than the yield from thermal cracking at 800°C. The weight of biochar was reduced by around 10% after the tar cracking experiment, which indicated that the biochar was stable under the experimental condition. Further study by conducting the tar cracking experiment using producer gas as carrier gas could elucidate the potential of the developed waste wood-derived biochar for industrial application.