Experimental study on filtration characteristics of a novel moving granular bed filter

Abstract

The effects of important parameters, such as moving speed, wind speed, particle layer thickness and dust particle size, on bed pressure drop and filtration efficiency of new moving granular bed filter were studied experimentally in this work, and the distribution law of collected dust was elucidated. The new granular bed filter, which adopts the moving bed continuous filtration method, has two inclined surfaces that can increase a flue gas particle contact surface and a baffle that can adjust the thickness of the filter material; thus, a high-efficiency filtration of fine dust and high performance for different environments is achieved, and the filtration characteristics of existing particulate filtration devices are improved. Experimental results show that the new moving granular bed filter demonstrates better dust removal performance than other granular layer dust collectors, thereby possibly achieving low bed resistance and high filtration efficiency and has wide adaptability. The selection of an appropriate filter medium and speed for the fine dust of 1–5 μm can maintain the filtration efficiency of the granular bed at 0.94 or more and the bed pressure drop at approximately 100 pa. The particle area with the most dust collection is on the windward side of the lower part of the granular bed, and several of the particles are replaced whilst the filter particles move. Furthermore, the dust collected by the particles in the dead zone cannot be replaced.