Applied Research Of Baghouse Airflow And Structural Optimization Of Coal-fired Heating Boilers

Increasingly stringent environmental standards for coal-fired heating boiler flue gas purification system put forward higher requirements, and dust removal system,as an important part of the overall flue gas purification system, occupy a pivotal position. Baghouse,less affected by the boiler load changes,ensure that dust emission concentr- ation at 20mg/m3 or less, and has a certain stability and reliability. But in actual operation bag breakage and large resistance loss often occur, which can adjust its internal airflow to extend bag life and lower operating resistance loss.Numerical simulation method,as one means of research baghouse internal air flow state,can provide effec- tive guidance to improve internal airflow dust and structural optimization.This paper took a straight baghouse of a 100t/h coal-fired heating boilers as the research object, studyed its internal flow field by using FLUENT, reasonably simplified its internal structure,combined with FLUENT and TECPLOT processing the results, used the bag unit head-on air velocity, the bag bottom updraft velocity, the bag unit side airflow velocity, flow distribution, and the collector resistance loss as the evaluation index to optimize the structure of collector.The following conclusions:1) In certain flow rate,increasing the number of air inlet reduced the pressure loss to a certain extent;2) The diversion channel had some effect on diversion, the bag unit head-on air velocity was significantly reduced, and reduced the scouring effect of dust the front bag;3) The ash hopper with suitable wind boards can significantly improve the spoiler, but the resistance loss increased slightly;4) A heating boiler precipitator dust removal system improvement program based on the installation, since it was put into operation, field test results show that dust is less than 600 Pa at full load resistance, 80% boiler load operation precipitator dust emission concentration is less than 20mg/m3, active duty to meet the national emission standards.And the numerical simulation results for the design and selection of heating boilers baghouse selection and the selection of the fan;5) Combined with FLUENT and TECPLOT for simulation processing, the air flow conditions inside the precipitator can be more clearly understood.