This invention discloses an
ammonia-based desulfurization
system and method based on zoned control, comprising a desulfurization
tower, an absorption circulation tank, an
ammonia water tank, a washing tank, and a process water tank. The desulfurization
tower, from top to bottom, has a
flue gas outlet, a demisting section, a second-stage
absorption layer, a first-stage
absorption layer, and a concentration section. The absorption circulation tank is divided into an upper oxidation tank and a lower absorption circulation section by a partition. The recovered liquid from the first-stage absorption is connected to the absorption circulation section of the absorption circulation tank via a pipeline; the oxidation tank has an
aeration pipe connected to the spray inlet of the second-stage absorption via a pipeline; the lower concentration section of the desulfurization
tower is connected to the oxidation tank via a liquid delivery pipeline. The washing tank supplies water to the demisting section and the absorption circulation tank; the
ammonia water tank replenishes ammonia water to the oxidation tank, the first-stage
absorption layer, and the absorption circulation section of the absorption circulation tank. This invention eliminates
coupling interference between absorption and oxidation by dividing the tank into zones within the same tank; combined with two-stage absorption and demisting
recovery, it effectively controls ammonia escape while ensuring efficient
sulfur dioxide removal.