Simulation of Adiabatic Gasification of Corn Straw using Air-Steam Blends as an Oxidizing Agent

Due to the increase of consumption in the world of energy and the pollution caused by fossil fuel combustion processes, it is necessary to generate new technologies for the use of alternative fuels, allowing to reduce the dependence on fossil fuels such as oil, gas and coal. In general, the combustion processes of fossil fuels produce greenhouse gases which increase the temperature of the environment and the deterioration of the ozone layer. Chemical equilibrium was used to estimate the species produced by adiabatic gasification with different air-vapor mixtures. By running the NASA CEA software (chemical equilibrium with applications), a thermochemical simulation was performed under two parameters: the equivalence ratio (ER) defined as stoichiometric air/air supplied to the reactor (1.5-6) and the steam-fuel ratio (0-1). Thus, the syngas composition showed the following ranges: CO (0% -14.7%), H₂ (0% - 36.7%), CH₄ (0% -4.3%), Co₂ (17% -22.7%). The calorific value of the gases and the energy conversion power were also calculated with the composition of the gases. Then, The Higher Heating Value (HHV) was calculated whose values aim to conclude that syngas generated can be classified as a poor fuel gas since the HHV ranged between 1992 kJ/SATP m³-7537 kJ/SATP m³.

Keywords: Chemical balance; Gasification; Calorific value; Corn straw