Patent ID: 8071036

Claim:
A mercury reduction system that reduces nitrogen oxide and mercury in flue gas discharged from a boiler, the mercury reduction system comprising: an oxidation-reduction agent supplying unit that sprays an oxidation-reduction agent for producing hydrogen chloride and ammonia when evaporated into a flue of the boiler in a liquid state, wherein the oxidation-reduction agent being sprayed into the flue in the liquid state evaporates and decomposes into hydrogen chloride and ammonia; a reduction denitration apparatus that includes a denitration catalyst for reducing nitrogen oxide in the flue gas with ammonia and for oxidizing mercury in a presence of hydrogen chloride; a wet desulfurization apparatus that reduces mercury oxidized in the reduction denitration apparatus with an alkali absorbent, an ammonia supplying unit that is provided between the oxidation-reduction agent supplying unit and the reduction denitration apparatus and supplies ammonia into the flue, and a hydrogen chloride supplying unit that is provided between the oxidation-reduction agent supplying unit and the reduction denitration apparatus and supplies hydrogen chloride into the flue, wherein the hydrogen chloride supplying unit or the ammonia supplying unit supplies at least one of the required HCl and NH 3 , if HCl concentration required for oxidizing Hg and NH 3 concentration required for reducing NO x are different.