Co-pyrolysis of Sewage Sludge with Distillation Residue: Kinetics Analysis via Iso-conversional Methods

This study explored the synergistic interaction of sewage sludge (SS) and distillation residue (DR) during co-pyrolysis for the optimized treatment of sewage sludge in cement kiln systems, utilizing thermogravimetric analysis (TGA) and thermogravimetric analysis with mass spectrometry (TGA-MS). The results reveal the coexisting synergistic and antagonistic effects in the co-pyrolysis of SS/DR. The synergistic effect arises from hydrogen free radicals in SS and catalytic components in ash fractions, while the antagonistic effect is mainly due to the melting of DR on the surface of SS particles during pyrolysis and the reaction of SS ash with alkali metals to form inert substances. SS/DR co-pyrolysis reduces the yielding of coke and gas while increasing tar production. This study will promote the reduction, recycling, and harmless treatment of hazardous solid waste.