Co-combustion of municipal solid waste and hydrochars under non-isothermal conditions: Thermal behaviors, gaseous emissions and kinetic analyses by TGA-FTIR

Co-combustion of municipal solid waste (MSW) with hydrochars was proposed as an effective way for both simultaneous treatments of MSW with biomass and energy recovery. In this work, thermogravimetric analyzer coupled with Fourier transform infrared spectrometer was employed to study the (co-)combustion, gaseous emissions and combustion kinetics characteristics of MSW, hydrochars and their blends. The addition of hydrochars to MSW leads to lower burnout temperatures and the shorter combustion time. Hydrochar prepared at 200 degrees C (SD200) has a better co-combustion performance than hydrochars prepared at 230 (SD230) and 260 degrees C (SD260) in term of ignition, burnout and comprehensive combustion characteristic index, hydrochar prepared at 260 degrees C has a better co-combustion evenness. The addition of hydrochar to MSW changed the gaseous products emission patterns of MSW and reduced the release of CO, HCN, NO and HCl. Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods were used to estimate the activation energy of MSW, SD200 and their blends, the minimum average activation energy was observed when the SD200 blending ratio was 70%, which was 75.65 kJ mol-1 by KAS and 82.12 kJ mol-1 by FWO, respectively.

Automated summary

Co-combustion of municipal solid waste (MSW) with hydrochars was found to be an effective method for waste treatment and energy recovery. The addition of hydrochars lowered the burnout temperatures and reduced the release of harmful gases. The hydrochar prepared at 200℃ (SD200) showed the best co-combustion performance among different hydrochars prepared at various temperatures.