1. If there is no bypass flue gas damper in the bypass flue, the flue gas pressure difference between the inlet and outlet sides of FGD must be adjusted to "zero" in actual operation to ensure the full flue gas desulfurization of FGD. It is difficult to maintain this state during operation, especially when flue gas operating conditions fluctuate.
2. If the FGD system does not have a bypass flue baffle, it is possible that part of the net flue gas may be re-inhaled into the FGD system or the original flue gas may be directly discharged into the chimney in actual operation. If FGD does not require high desulfurization efficiency, the bypass baffle door can be omitted, but for FGD systems that require high desulfurization efficiency, the bypass baffle is very necessary.
3. If the bypass baffle is not installed in the FGD system, a certain margin must be considered when selecting the capacity of the booster fan, and the cost and operating cost of the booster fan will increase.
4. When the FGD device starts and stops, the flue gas needs to take a bypass. The bypass baffle is opened as required, and the FGD inlet and outlet baffles are closed at the same time. The bypass baffle can be adjusted to be with the FGD inlet and outlet baffles by controlling the opening. The opening and closing of the door are coordinated, so that the difference in resistance of the two flues will not significantly affect the negative pressure of the boiler furnace and cause the boiler MFT.