Fluidized Bed Chemical Reactor Simulation And Expert Systems

The mass balance equations of the bubble phase and the dense phase of a fluidized bed have been built in this thesis by introducing Damkohler number of a chemical reactor and Mbe number, a mass transfer number between the bubble phase and the dense phase. The mass balance equations are solved numerically by 4th-order Rong-Kutta method to get the conversion degree versus Da number, and Mbe number for different reaction orders for Geldart A group particles and Geldart B group particles respectively. Comparisons have been with the classical approach, which assumes that the concentration gradient is neglected in the dense phases. The results show that the relative error is less than 5 percent for group A particles, whilst it is up to 40 percent for group B particles. Furthermore, in this thesis the characteristic time of the mass transfer between a bubble and the dense phase, and the characteristic time of the reaction between a particle and gases have been developed. Based on the characteristic times the design-operation chart of fluidized bed reactors has been given.By the methodology of expert systems, a database for the design of fluidized bed reactors is set up and simulation software for fluidized bed chemical reactors is built up. The database and the simulation software blocked according to its functions, thus the integrated design environment is established with auxiliary drawing. The conceptual design of a fluidized bed reactor could be fully computerized.