Investigation on the characteristics and interaction of co-pyrolysis of organic hazardous wastes

Here, the pyrolysis decomposition behavior and kinetics of four kinds of organic hazardous wastes (OHWs) and their blends were investigated. The four types of OHWs are oil sludge (OS), paint sludge (PS), waste print circuit boards (WPCBs), and penicillin fermentation residue (PFR). A combination of thermogravimetry (TG) and derivative thermogravimetry (DTG) analysis was employed with Gaussian multi-peak fitting and Flynn-Wall-Ozawa (FWO) method. The results showed that OS was mainly pyrolyzed at 550–900 °C while PS, WPCBs, and PFR were mainly pyrolyzed at 150–550 °C. During co-pyrolysis, the PS/PFR exhibited the best pyrolysis performance among all the blends due to the high volatiles content in PS and PFR. The interaction analysis revealed that OS/PS exhibited the lowest coefficient of residue percentage compared to other blending samples, with OS/PFR following behind. This observation indicates a synergistic promotional effect between OS and PS, as well as between OS and PFR, during the co-pyrolysis process. Gaussian fitting showed that the carbonate decomposition peak of OS shifted towards lower temperatures during its co-pyrolysis with PS and PFR. [Display omitted] •Mono- and co-pyrolysis behavior of organic hazardous wastes were investigated.•PS/PFR exhibit the best co-pyrolysis performance among all the blends.•Possible interaction effects during co-pyrolysis were analyzed.•Synergy effect is observed during co-pyrolysis of OS/PS and OS/PFR.•Carbonate decomposition peak of OS towards lower temperatures during co-pyrolysis.