Thermal Performance Analysis of Materials and Configurations for Cylindrical Sidewalls of Charcoal Kilns

Abstract

Most of the charcoal in the world comes from small and medium-sized producers, using rudimentary carbonization kilns that require significant time or energy during the heating and cooling stages of the process. Despite advances in improving the performance, the influence of materials used in the sidewalls of these kilns has been scarcely studied. Therefore, based on numerical simulations, the present study analyses the thermal performance of cylindrical sidewalls composed of combinations of metallic materials, ceramic materials, and insulating blankets grouped in three configurations: configuration I (sidewall with just one material), configuration II (sidewall with two materials assembled in series), and configuration III (pivoting sidewall). Results were encouraging, especially when comparing kiln configuration I with the novel configuration III. Simulations suggested that the proposed configuration III could reduce the heating time by 62%, the cooling time by 91%, the heat supplied to sidewalls by 80%, and the heat loss to the external environment by 99.7%. The save of wood charged into the charcoal kiln grew up to 7.3 times, varying the thickness of the inner layer of the sidewall.