Numerical Simulation Of Internal Flow Field And Dust Removal Efficiency For Electrostatic Precipitator Of 1000MW Unit

The year-on-year increase in coal consumption in China and the increasingly strict environmental protection regulations will inevitably put forward higher requirements for the standards of coal-fired boiler exhaust emissions.Electrostatic precipitator has become the most widely used dust removal equipment because of its high dust removal efficiency,low pressure loss and low cost of operation and maintenance.Currently,some progress has been made in the numerical simulation of electrostatic precipitators,but the research models are mostly based on the size of the experimental electrostatic precipitator,which is different from the actual parameters and operating conditions of the actual electrostatic precipitator.In order to correctly reflect the actual situation of fine dust removal in the electrostatic precipitator,this paper firstly tests the dust concentration of the inlet and outlet of the electric precipitator of a 1000MW unit of a power plant,and then uses Fluent under the condition of no electric field and particle phase.The effects of porous plate arrangement,perforated plate opening rate and the presence or absence of ash baffle on the uniformity of the flow field in the electrostatic precipitator were studied.Quantitatively,the flow field uniformity can be optimized by using a three-layer porous plate arrangement and an opening ratio of 0.5/0.3/0.3.Finally,based on the optimization of flow field,the electric field,flow field and particle phase motion are simulated by multi-field coupling,and the gas field characteristics and particle collection efficiency of the horizontal spike-plate type electrostatic precipitator are studied.Specifically,the effects of outlet pressure,velocity of inlet airflow,operating voltage,dust concentration,size of dust particle,polar matching parameters and different corona electrode structures on dust removal efficiency were studied.The quantitative results were as follows:(1)Reduce the absolute value of outlet pressure,reduce the velocity of inlet airflow,increase the operating voltage,stabilize the dust concentration at 30g/m~3 and increase the dust condensation rate can optimize the dust removal efficiency of the electrostatic precipitator;(2)Appropriately reduce the distance of the wire-board,the distance of the wire-wire and the diameter of the corona wire can obtain better dust removal efficiency,The specific parameter selection should be combined with the actual project;(3)BS electrodes has obvious dedusting performance superior to other electrode structures due to its tip protrusion,but the adaptability to coarse dust particle size is poor.The research results in this paper are expected to provide useful theoretical guidance for the design,selection and structural optimization of the electrostatic precipitators of the 1000MW unit.