On-line analysis of the correlation between gasification characteristics and microstructure of woody biowaste after hydrothermal carbonization

Woody biowaste is a component which is difficult to be converted among multiple solid waste (MSW) during the hydrothermal carbonization (HTC). In this paper, poplar sawdust was pretreated by HTC to study the correlation between microstructure and gasification characteristics. The results showed the fixed carbon and higher calorific value increased from 13.44 % and 19.41 MJ/kg to 41.47 % and 25.85 MJ/kg after HTC, respectively. The cold gas efficiency of hydrochars prepared at 220 degrees C was the highest of 93.57 % compared with that of raw material of 76.65 %. It was found that carbon structure had a greater influence on hydrochars gasification characteristics than pore structure. The crystallinity of hydrochars had a good correlation with the total yield and H2/CO of syngas, which can provide guidance for HTC pretreatment of woody biowaste and MSW.

Automated summary

This study pretreated poplar sawdust by hydrothermal carbonization and found that the fixed carbon and higher calorific value of hydrochars significantly increased. The cold gas efficiency also improved, with carbon structure having a greater impact on hydrochars gasification characteristics. The crystallinity of hydrochars showed correlation with the total yield and H2/CO of syngas.