Comprehensive Numerical Simulation For Coal Hydrogasification And SOFC

According to the world's energy constitution, coal is and will be the primary energy source nowadays and in the foreseeable future. Near Zero Emission Coal (ZEC) is an advanced technology for clean and highly efficient utilization of coal. In this dissertation, the process of hydrogasification of the given coal and Solid Oxide fuel cells(SOFC) technology were discussed based on the near ZEC utilization technology.A thermodynamic mathematical model for given coal gasifier was set up with respect to the influence of operation conditions, agent for gasification. The model combines the chemical equilibrium and the thermodynamic equilibrium of the global reaction which is general and can be used in most kind of coal partial gaifier. The final composition, the percentage of gas composition, and coal conversation rate can be predicted by this model. The calculated results are very close to the referenced experimental data. With this model, the performance of the coal gasifier under different operation conditions such as reaction temperature and the influence of the gasifying relative fuel/H2 ratio were also carried out in this dissertation. Using the FLUENT software, the coal hydrogasifiation characteristics were modeled for a 200 t/d entrained flow hydrogasifier. The contours of inner temperature, velocity and the distribution curves of CH4 and H₂ are presented for this gasifier. The simulation results are in good agreement with the experimental or reference data and the theoretical results.The SOFC have also been analyzed by the flow sheet software, Aspen Plus. The model is able to provide detailed thermodynamic and parametric analyses of the SOFC operation. Validation of this model is performed by comparison to the experiment data. Sensitivity analyses of major operation parameters were performed using the developed model. Besides, the paper builds two other models from different considerations.The research efforts and the preliminary results will put forward the system design, optimization, the research of operation characteristics as well as developing new near zero emission coal utilization system.