High running resistance and frequent bag broken occurred all the time on 2×300t/h circulating fluidized bed(CFB)boilers in Inner Mongolia Erdos Shuangxin power company.Therefore

experimental test and numerical simulation were conducted to systematically investigate the filter-bag broken reasons

gas parameters

dust collector structure and flow field distribution.Moreover

several measures were taken to optimize the bag dust collector

such as changing the original precipitator's intermediate gas admission into two sides horizontal direct gas admission

adding shell with length of 4 500mm and steel bracket at inlet of the original precipitator

up moving the original upper and middle boxes by 3 000mm and extending the filter bag to 7 550mm.After the transformation

the dust emission was reduced below 30 mg/m3

the equipment running resistance was decreased by 700Pa

the electricity consumption of induced draft fans was dropped

and the filter bag's broken problem was solved.The optimization realized stable operation of the boilers under full load condition

which could generate economic benefits of 1.552 6×107yuan every year.