| Popis: |
In this paper, a detailed 3D computational fluid dynamics (CFD) model for two-stage entrained flow dry feed coal gasifier was developed. With the standard computational fluid dynamics (CFD) software FLUENTO15.0, a number of simulations were conducted to show the process of coal gasification at different coal and oxidant ratio, and to form the distribution between the two stages of the gasifier. Based on published experimental results, we investigated firstly different reaction mechanism for the validated model. And then investigations were made through the validation of the model for crucial parameters such as species concentration, char conversion and so on. At the first stage, the distribution of Coal is 50% and Oxygen is 60%, and the distribution of Coal is 50% and Oxygen is 40% at the second stage. According to per reference experimental conditions, the overall Oxygen/Coal (O/C) ratio was maintained at 0.9, 1.0, 1.1 for preliminary validated study. The analysis of the results show that the composition of syngas at the exit of gasifier are quite similar to the referred experimental case in conditions of E. And when the Oxygen/Coal (O/C) ratio is equal to 1.0, overall performance is optimized, such as syngas, temperature and carbon conversion. |
