The invention relates to a wet desulfurization
tower based
flue gas desulphurization method capable of enhancing the adaptability to
low load, solving the problems as follows: when the load of the desulfurization
tower is lowered (the load is lower than 30% of the amount of
flue gas under rated load of the desulfurization
tower), the amount of the
flue gas flowing through the desulfurization tower is lessened; therefore, the demisting efficiency of a
demister can not be maintained, the desulfurization efficiency is reduced and
fly ash and liquid drops at the entrance and exit of the tower settle. The method mainly comprises the following steps: exhausting the
flue gas desulfurized in the desulfurization tower after being demisted; and separating partial purified
flue gas from all the purified
flue gas under automatic regulation of a circulatory flue gas
regulator when the load of a desulfurization
system is lower than 30% of the rated load, and ensuring the partial purified flue gas to return back to the entrance of the desulfurization tower via a circulatory flue gas
pipe, thus accelerating the air speed in the tower and ensuring the flue gas load in the desulfurization tower at the
lower limit of at least 30% of the rated load under which the desulfurization tower can operate stably. The method enables the wet desulfurization tower to safely and stably operate under the condition of meeting 0%-110% of rated load and obviously enhances the adaptability of the desulfurization
system to
low load.