Abstract： Based on one 2 × 300 MW subcritical circulating fluidized bed unit enterprise, the SO2 concentration at the inlet of the flue gas fluctuates greatly, and the SO2 concentration fluctuates irregularly with strong randomness. During the operation of the desulfurization unit, the circulating volume of limestone gypsum slurry needs to be adjusted according to the operating load of the unit and the change of flue gas parameters. In order to ensure that the SO2 concentration in the flue gas at the outlet meets the discharge standard, three slurry circulating pumps are usually started, resulting in the phenomenon of "big horse pulling small car" of the power frequency slurry circulating pump. This paper discusses the frequency conversion transformation of slurry circulating pump, and analyzes the frequency conversion transformation of the slurry circulating pumpaccording to the actual operating condition of the enterprise. The results show that the B pump of four slurry circulating pump is selected for frequency conversion transformation, calculates the frequency conversion range of slurry circulating pump is 45 ~ 50 Hz, and achieves the purpose of energy saving and consumption reduction while meeting the standard emission.
