Modeling of a fluidized bed combustor with immersed tubes. Quarterly report, September--November 1975

Abstract

A mathematical model of a fluidized bed combustor is being developed which will include coal combustion phenomena and will incorporate basic mass transport relationships, bubble mechanics, heat transfer and configuration effects. A cold model test bed will be designed, constructed and operated to generate data in support of the effort in developing the mathematical model. In particular, experiments will provide data concerning heat transfer effects of tubes and tube bundles in fluidized beds, bubble formation, dispersion etc. Numerical solutions are presented for the conversion-time relationships for the isothermal and nonisothermal gas-solid reactions to examine the effect of change in particle size as it reacts. Particular attention is focused on the influence of the intermolecular and intraparticle diffusion resistances as well as of the mass and heat transfer coefficients on conversion-time relationships for the particles exhibiting different growths. A fluidized bed reactor, which consists of a fluidization column, air supply system, water supply system, an off-gas system, and instrumentation for temperature and pressure measurement, has been fully designed and its fabrication is almost completed. Most of the equipment needed for experimentation has been received except an air compressor, and temperature measuring and recording instruments which are under order.