Interaction effects between three typical components of municipal solid waste during their co-hydrothermal carbonization and co-gasification

Hydrothermal carbonization (HTC) followed by gasification technology is a promising process to realize the high efficient and clean utilization of municipal solid waste (MSW). However, the complex components of MSW made it difficult to understand the gasification mechanism. In this paper, the individual and co-HTC coupled with gasification of three typical components of MSW (disposable bamboo chopsticks (DBC), waste paper (WP) and peanut shells (PS)) were investigated to reveal their interactions and the combining effect of interactions and HTC on the gasification reactivity. The results showed that the antagonistic effect existed between WP and PS during the co-HTC process, reducing the yield of co-hydrochar. For WP and DBC, the synergistic effect between them was present during the co-HTC at the WP proportion of 25%, but changed into an antagonistic effect at the higher proportion. The gasification reactivity of DBC and PS was dramatically decreased by HTC treatment because of the remove of active minerals or the increase of aromatization degree, but significantly improved via the addition of WP due to the significant synergistic effect between their hydrochars. Retention of Ca element and the higher content of volatiles in WP were two possible factors causing the synergistic effect during the co-gasification.