Filtration of dust in an intermittent moving granular bed filter: Performance and modeling

Abstract

In this work, a new cross-flow intermittent moving granular bed filter was developed and tested. The filter performance was investigated by using airflow at room temperature and under different experimental conditions. The total collection efficiencies obtained were in the range between 82.0% and 99.8%. It was employed different superficial gas velocities, inlet dust concentration and types of dust, with partial substitution of the granular material during the operation in some runs. Macroscopic models to describe the granular filtration based on the assumption of uniform particle deposition were utilized. The characteristic parameters of the filtration were obtained as a function of the average mass specific deposit, expressed as the average relative filter coefficient and the average pressure drop ratio. For the relative pressure drop ratio, the correlation proposed by Ives (1969), resulted in the best curve adjustment. For the relative average filter coefficient, it has been proposed a modified model from Ives (1969) correlation. The filtration parameters presented a dependence on the properties of each particulate employed. These models were used to simulate the filter operation for each experimental run, including the partial granular material substitution cases. The total collection efficiency for different particle size range was determined and used for a prediction test of the average relative filter coefficient.