Experimental Characterization of the Combustion Process of Briquettes From Corn Cob and Coconut Fibers Residues

Abstract

This study presents the experimental combustion characteristics of biomass briquettes made from agricultural wastes (coconut fiber and corn cob) of Córdoba-Colombia. For this thermochemical conversion, the actual heat transfer during the process and the main combustion characteristics are also studied. Initially, several corncob and coconut fibers briquettes were produced and burned. The non-adiabatic flame temperatures and the air velocity were measured. To study the combustion process dynamics, a process simulation was performed in EES Software© using the typical mass balances of a combustion process, and taking into account the possible stoichiometric equation, using as input the elemental analyzes of each biomass and the excess air that was determined experimentally. The exhaust gases and completeness combustion with moist air were evaluated and usual combustion parameters and correlations like energy balance, enthalpy of formation of the exhaust gases and process exergy were calculated. Likewise, the heat transfer by convection, radiation and heat flow at the gas outlet was evaluated, referenced to the process temperatures. It was found that values of non-adiabatic flame temperature were around 500 ° C, while surface and gases temperatures were between 60–81 ° C and 60 ° C respectively. In general, low emissions of harmful gases to the atmosphere were generated during the combustion of these briquettes. As well, the energy availability at the outlet can be used for moderate heating processes. These findings make these types of biomass a viable alternative to be utilized as renewable energy source.