In selective catalytic reduction(SCR)denitrification process in coal-fired power units

the precision of flue gas flow plays an important role in control of ammonia injection.It is difficult to measure the flue gas flow precisely in short straight ducts of large cross-section area with high concentration of dust in the flue gas.A theory method based on coal-fired calculation and an online multi-flowmeter based on differential pressure is put forward.Moreover

this method was applied in in-situ measurement of flue gas from the denitration system of a 330 MW unit boiler.The application results show that

at unit load of 330 MW

the deviation between the online measured value and the actual measured is 5.36%

which is small

verifying this multi-flowmeter is more feasible for the flue gas flow measurement and allows the denitrification system to provide more precise control and monitoring.