A general method for the determination of the entrainment in fluidized beds

Abstract

The measurement of the entrainment is complicated in a hot fluidized bed. Therefore, the entrainment or cycle rate of the total bed material inventory is typically estimated via mass and energy balance for e.g. the sorption enhanced reforming process. The sorption enhanced reforming process is an advancement of the conventional dual fluidized bed steam gasification process. It aims for the production of a hydrogen-rich product gas. The process is highly depends on bed material cycle rate, respectively bed material entrainment. Only limited knowledge about simple modelling methods of the entrainment of a fluidized bed are available to validate the cycle rate calculated by mass and energy balances. Therefore, measurements of the bed material entrainment at two different plants were conducted and a model based on easily accessible parameters for the entrainment of fluidized bed risers is presented. It is also verified, that the results from mass and energy balances fit well with the measured data for the entrainment.