Oxidation reactions of solid carbonaceous and resinous substances in supercritical water

Recent kinetic studies, particularly those by means of shadowgraphy and X-ray radiography, for supercritical water oxidation of solid carbonaceous and resinous substances have revealed the importance of the O2 mass transfer process over the intrinsic surface reaction at higher temperatures. The mass transfer processes, internal and external one, should be incorporated in designing SCWO processes for solid substances and related processes such as catalytic SCWO. Some model calculation efforts of late are briefly described. Finally, fundamental information required for future development is itemed.

Graphical abstractRecent kinetic studies, particularly those by means of shadowgraphy and X-ray radiography, for supercritical water oxidation (SCWO) of solid carbonaceous and resinous substances have been reviewed. The importance of the O2 mass transfer process at higher temperatures was revealed as shown in the pictogram. Some model calculation efforts are briefly described and fundamental information required for future development is itemed.Oxidation reaction rate q vs reciprocal temperature of carbon particles in SCWO at 30 MPa. The rate above 400 °C is mostly controlled by the O2 mass transfer rate, qmass, indicated by an arrow. Reproduced with some modification from Koda et al. [S. Koda, K. Maeda, K. Sugimoto, M. Sugiyama, Oxidation reactions of solid carbon in supercritical water, Combust. Sci. Technol. 178 (2006) 487–507] with kind permission of Taylor & Francis (License No. 1994520695868).Figure optionsDownload full-size imageDownload as PowerPoint slide