Hydrodynamic Aspects of Spouted Beds at Elevated Temperatures

Abstract

A spouted bed was used to study the effect of temperature on hydrodynamic performance, as measured by parameters such as pressure, minimum spouting velocity, and spout-annulus residence time distribution. Three bed temperature regimes were investigated: ambient, preheat (∼200^°C. using a small hydrogen pilot flame), and combustion (∼800^°C, using a premixed toluene flame). A stable operating regime for the system under combustion conditions was characterized on a plot of gas velocity vs. equivalence ratio. Pressure and temperature profiles in the bed were developed. The effect of temperature on the minimum spouted velocity was evaluated in terms of the minimum spouting Reynolds number, Re_ms, and the Archimedes number. The effect of particle shape on spout-annulus flow disribution appeared to be greater than the effect of temperature.

Key words:

• Spouted bed
• hydrodynamics
• effect of combustion temperature
• residence lime distribution