The invention discloses a method for treating desulfurization ash. The method comprises the following steps of: mixing the desulfurization ash generated by a dry / semidry desulphurization process and limestone
powder, which serve as raw materials of a desulfurizer in a wet
flue gas desulfurization process, according to a proportion; uniformly stirring the desulfurizer and pumping the desulfurizer into a
slurry pond of an absorption
tower; adding a catalyst into the
slurry pond; introducing oxidation air into the
slurry pond; introducing
flue gas into the slurry pond through a
flue; reacting the desulfurizer with SO2 in the
flue gas under the action of the oxidation air and the catalyst; controlling the pH value of the slurry in the absorption
tower, the slurry temperature, the content of
solid matters contained in the slurry and the
retention time of the desulfurizer in the slurry pond; after the reaction is completed, performing vortex concentration and vacuum
filtration to obtain a
gypsum by-product; and adding
wastewater produced in the process into a process
water collection box for recycling. The method is simple, is easy to realize, has remarkable effect, provides a safe and
proper treatment way for the dry / semidry desulfurization ash and has good economic and
social benefits.