Economics of hydrothermal carbonization of biogas digestate in a hybrid AD-HTC plant

In the recent years hydrothermal carbonization (HTC) has become subject to research again and therefore to numerous scientific publications. To date most of this research revolves around the chemical and technical optimization of the HTC process itself, HTC of different biomasses, and the entire spectrum of hydrochar application. A current search reveals, that only very little has been published on the economics of HTC. This is mostly due to the fact, that reliable economic assessments need to be done on the basis of well-defined technical processes and erecting of larger scaled research/commercial plants has even begun within the last couple of years. In this sense the paper at hand analyses the economic viability of hybrid anaerobic digestion (AD) and HTC plants taking into account that there are a number of interesting synergies that can be realized by combining these different types of bioenergy plants.