Study On The Optimization Of Flow Field In Bag Filter

With government's requirement to environmental protection getting stricter and air pollution problem is becoming more and more highlighted,which improve the technical requirement for dedusting.However,short working life is the main problem which limit the promotion of bag filter.Airflow distribution was one of the most important factors that affected collection efficiency,running resistance and longevity of filter-bag in a bag filter.Based on the relations with airflow-particles removing-flow of each bag,the paper simulated the airflow distribution in bag filter with computational fluid dynamics numerical simulation,got the velocity field,pressure field,the movement track of particles and the flux distribution of every filter-bag.We analyzed forming reason of the non-uniform airflow distribution from perspective of airflow containing dust,and built evaluation methodology about the uniformity of airflow,these works provide theoretical basis for further improvement of the design method.According to the simulation result,these was a high speed jet caused great erosion on the windward side of the filter-bag,a clear vortex formatted in ash bucket.Furthermore,the flow load is uneven between compartments,the last few rows filter-bags in bag filter have the risk of overall broken.The results of simulation calculation were basically consistent with those of local test,which provided reference data for optimizing structure design of airflow distribution in bag filter.By simulating the airflow organization in different mode,the influence of airflow uniformity panels,flow-guided structure and different filter-bag permeability on airflow uniformity was studied,which made the airflow distribution more uniform and reduced the damage on filter-bags.The results of this study will be useful to optimize the design andretrofit of bag filter or electrostatic-bag precipitator, improve the efficiency and reliability,enhance the bag filter benefits for environment and economy.