Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
STUDY OF THE COMBUSTION OF BIOETHANOL WITH EXCESS OF WATER USING A POROUS BURNER WITH COUPLED EVAPORATOR
Submission Author:
Mauro A. Moreira Gonçalves , SC
Co-Authors:
Mauro A. Moreira Gonçalves, Roberto Wolf Francisco Jr.
Presenter: Mauro A. Moreira Gonçalves
doi://10.26678/ABCM.COBEM2023.COB2023-1622
Abstract
Currently, there is much interest in the production of bioethanol from renewable raw materials, mainly sugarcane and corn, in order to minimize carbon dioxide emissions, a greenhouse gas that contributes to global warming. Data on the global production of bioethanol show that Brazil and the USA were responsible for 84% of the annual supply (88 of 105 billion liters) in 2022, with a plan to grow 4% per year until 2032, seeking to replace fossil fuels and their reservoirs finite. Also, during the ethanol production process, a distillation step is necessary to reduce the concentration of water present in the mixture, thus increasing the degree of purity of the fuel. The reason for this is that the use of raw bioethanol, with excess water, results in operating instability problems and requires higher energy rates in the fuel evaporation stage. However, for higher concentrations of ethanol, the cost of the distillation process ends up increasing the final value of the product. Thus, the objective of this project is to evaluate the burning of raw bioethanol, with excess water, using a porous burner and an evaporator coupled to the system. This evaporator is made of stainless steel 304L and was inserted around the porous medium, thus allowing the evaporation of the liquid fuel mixture with the heat generated by the combustion reaction itself. Then the fuel is pre-mixed with air and injected into the burner. The parameters evaluated experimentally were the heat transfer rate from the flame to the evaporator, the burner stability range, the radiation efficiency and the pollutant emissions. The analysis of the evaporator coupled to the burner was initially performed using pre-mixed methane and air, equivalence ratio of 0.5 and power range between 0.4 and 3.1 kW. In this condition, the rate of heat transfer to the evaporator measured experimentally represented about 10% of the energy generated by the combustion reaction. Radiation efficiency was around 18 to 22%. For a power of 3 kW using anhydrous ethanol, the energy required to evaporate the mixture is 76 W. The increase in the fraction of water in bioethanol results in an increase in the amount of energy required in the fuel evaporation step.
Keywords
bioethanol combustion, porous medIa burner, evaporation heat transfer, liquid fuel, flame stability, Biofuels (ethanol)
