The invention relates to a
flue gas semidry desulfurization method and a
flue gas semidry desulfurization device.
Flue gas enters an anterior desulfurization stage, and contacts a desulfurization agent, such that partial
sulfur dioxide is removed, and anterior-stage desulfurization is finished;
flue gas discharged from the anterior-stage desulfurization process enters a anterior-stage deduster, such that
solid particles comprising the desulfurization agent is removed, and anterior-stage dedusting is finished;
flue gas discharged from the anterior-stage dedusting process enters a posterior desulfurization stage, such that rest of
sulfur dioxide is removed, and posterior-stage desulfurization is finished;
flue gas discharged from posterior-stage desulfurization process enters a posterior-stage deduster, such that
solid particles comprising the desulfurization agent is removed, and posterior-stage dedusting is finished. According to the invention, through steam
humidity regulation and two-stage desulfurization,
sulfur dioxide in
exhaust gas can be absorbed highly efficiently. The
humidity of
flue gas or dry-
powder desulfurization agent is regulated by using waste steam, such that scaling of the desulfurization agent in the desulfurization
tower is avoided, such that
system stable operation is facilitated. During the desulfurization process, with the anterior and posterior desulfurization reactions,
flue gas desulfurization efficiency is ensured. Desulfurization agent recovered from the deduster and the desulfurization
tower is circulated again to the anterior-stage desulfurization
tower. With multiple times of circulation, desulfurization efficiency of the desulfurization agent is improved.