In HTC process, the carbonization temperature is moderate ,ca. 180-250 °C in autogeneous pressure, and the carbonization is performed in the presence of water for 1-6 hours. The advantages with HTC is that different materials, e.g. wood, leaves, cellulose, hemicellulose, lignin, forest- and agro residues, microalgae, animal manure, municipal waste and different biosludges with very low dry content (5-10 wt-%) can be processed. The overall carbonization reactions might be exothermic, which makes the process energy-efficient.
Earlier research examples
We have used high temperature carbonization e.g. for production of carbon nanofibres from wet-spun cellulose fibres and electrospun polyacrylonitrile
Figure. a) Carbon particles from kraft lignin by HTC and b) HTC carbonized unbleached softwood pulp.
 Wikberg, H, Grönberg, V. and Harlin, A. (2013) “Hydrothermal carbonisation (HTC) of wood components with high carbon content”, 17th International Symposium on Wood, Fibre and Pulping Chemistry (ISWFPC). Vancouver, Canada, June 12-14.
 Grönberg, V., Wikberg, H., Hentze, H.P., Harlin, A. and Jääskeläinen, A.-S. (2012) “Process for the hydrothermal treatment of high molar mass biomaterials” VTT Patent application PCT/FI2013/051180.