A method for estimating the solids circulation rate in a closed-loop circulating fluidized bed

We propose a simple method for accurately estimating the solids circulation rate in a closed-loop liquid–solid circulating fluidized bed. The technique is based on the use of radioactive isotopes for estimating the solids velocity and volume fraction distribution in a chosen section of the circulating fluidized bed loop. The method is demonstrated for a liquid–solid circulating fluidized bed, and is readily applicable in other systems such as gas–solids circulating fluidized beds or closed-loop pneumatic and hydraulic transport lines. With minor modifications, the method may be used for industrial systems as well.