Carbonization using an Improved Natural Draft Retort Reactor in India: Comparison between the performance of two woody biomasses, Prosopis juliflora and Casuarina equisetifolia

Charcoal is an impure form of carbon, containing some organic matter and ash. It is derived from wood by removing the volatile organic matter and the moisture, through carbonization. Charcoal is widely used as a fuel for domestic and industrial heating applications in developing and underdeveloped countries. This research article describes the carbonization of two different woody biomass species – Prosopis Juliflora Wood (PJW) and Casuarina Equisetifolia Wood (CEW) – at different final carbonization temperatures, from 400 °C to 700 °C, through an improved natural draft charcoal retort (INDCR) reactor. The maximum yield of charcoal at 400 °C and of fixed carbon content at 700 °C, obtained from Casuarina wood, are 41.15wt% and 87.78wt%, respectively. Further, the combustion reactivity of the produced char samples was measured through thermogravimetric analysis. The results indicate that the char with higher volatile matter has a maximum burnout efficiency and charcoal reactivity. The PJW and CEW char activation energy increased from 68.28 KJ/mol to 79.32 KJ/mol and from 53.97 KJ/mol to 62.03 KJ/mol, respectively with the increment of carbonization temperature from 400 °C to 700 °C. The kinetic study of charcoal combustion concludes that PJW and CEW charcoal can be widely used for blast furnace and barbeque applications.