Experimental investigation of hot water cogeneration using a carbonizer fit out with a preheating system

Carbonization is a thermochemical process that generates thermal energy and charcoal. The system allowing to recover the heat energy for co-, tri- and multi-generation is currently more investigated. The use of multi-generation systems is beneficial from the standpoint of increasing the usage of biomass, energy efficiency and reducing the impact on forests. The aim of this article was to design a carbonizer fit out with a thermal insulation layer and use it for the carbonization of some local biomasses, namely wood chips and teak wood. A heat recovery system was then incorporated into the carbonizer to cogenerate hot water from the thermal energy induced by the carbonization process. The results obtained with the designed carbonizer were 20% and 26% in mass yield respectively for teck wood and wood chips. The system developed that heat recovery was able to generate 25 L/h hot water at 45°C and 50°C during the first and the last phases respectively for wood chips and teak wood carbonization. The introduction of the preheating system induced a significant rise of the water’s temperature. The highest maximum value of the hot water temperature was 62°C obtained during the carbonization of both studied fuels.