Study On The Performance In A Coupled Cyclone With Annular Louver Granular Bed Filter

In the process of using fossil energy,it is inevitable to produce dust which will bring about serious environmental pollutions.Cyclone separator,particle bed filter and other gas purification equipment were widely used in industrial fields,but the purification effect of individual equipment is often difficult to meet the increasingly stringent environmental protection requirements.Our previous studies have proposed a separator coupling a cyclone with a inner built-in granular bed,the centrifugal separation of the cyclone separator and the filtration/adsorption separation of the moving bed are combined in one apparatus therein the synergistic strengthening of two mechanisms is realized,which can achieve better purification effect for dusty gas.However,the outer wall of built-in granular bed is made of Johnson screen,which will form filter cake and adhere to its surface in long-time operation.Thus it is easily to lead to continuous increase of equipment pressure drop.In order to meet the needs of low pressure,high efficiency and wide operation flexibility in the separation process,a coupling separation with cyclone-annular louver granular bed is put forward in this paper.In order investigate two different types of louvered outer wall granular bed structures(the annular louvered granular bed without straight edge and the annular louvered granular bed with straight edge),the equipment static pressure distribution,the three-dimensional velocity field distribution and the granules carry out rate of these two built-in beds under dust-free load were scrutinized through large-scale cold model experiments.Under the condition of dust load,the effects of operating parameters including the inlet gas velocity,the inlet dust concentration and the granules circulation strength on the separation performance were analyzed.These two proposed built-in bed types with the original built-in bed type(Johnson screen tube wall outer wall granular bed)were compared under the same operating conditions.The results show that the cyclone annular louver granular bed equipment can be operated stably.Compared with the original built-in bed equipment,the pressure drop increases slightly.The pressure distribution and velocity distribution in the cyclone shell vary obviously at the upper end of the straight cylinder section(the region of sharp gradient variation),captured particles might be carried out of the bed therein.The proposed built-in bed equipment has quite desirable dust removal performance and stable operating pressure drop.No large amount of dust accumulation is seen in the long-time experiment.Under the same operating conditions,the capture efficiency is significantly improved compared with the original Johnson screen built-in bed equipment.