Development of a semi-empirical model for woody biomass gasification based on stoichiometric thermodynamic equilibrium model

Abstract

The gasification process is a complex biomass conversion process, so mathematical models are a useful tool to support its study. This work aimed to develop empirical correlations for the prediction of tar and coal and methane and apply these correlations, and then proposed and evaluated models based on the thermodynamic equilibrium model. Based on the empirical correlations developed (R-squared of 0.75, 0.77 and 0.64) 6 modified models were proposed, which were compared to the basic model. The M6 model that applied the three empirical correlations in its resolution was the model that best described the experimental results. It was concluded that the application of empirical correlations can improve the prediction of the behavior of a downdraft gasification system, achieving a reduction in the root-mean-square error of up to 52% of the value compared to the basic model, without the application of empirical correlations. The novelty of this study part of formulated the models by combing the empirical correlations in different ways with other strategies to correct the nonequilibrium deviations, in a manner that predicts gas composition and simultaneously fractions of tar and char, both undesirable compounds and main problems in syngas application.