Patent ID: 9132391
Filing Date: 2015-09-15
Classification: B01D,B01F,F23J

Abstract:
1. An air pollution control device for reducing amounts of a nitrogen oxide and mercury contained in a flue gas from a boiler, the device comprising: a reduction-oxidation auxiliary agent supply unit having a spray nozzle for spraying in a liquid state a reduction-oxidation auxiliary agent that produces an oxidizing gas and a reducing gas upon gasification thereof into a flue gas duct at a downstream of the boiler; a mixing unit provided on a downstream side of a region where the reduction-oxidation auxiliary agent is gasified, for promoting mixing of the oxidizing gas and the reducing gas, which are produced upon the gasification of the reduction-oxidation auxiliary agent, with the flue gas; a reduction-denitration unit including a denitration catalyst for reducing a nitrogen oxide in the flue gas with the reducing gas and for oxidizing mercury under coexistence with the oxidizing gas; a wet desulfurization unit for reducing the amount of mercury oxidized in the reduction-denitration unit using an alkali absorbent, mixing promoting auxiliary members including a plurality of guide vanes connected to each other provided upstream of the reduction-denitration unit and downstream of the mixing unit, for promoting the mixing of the oxidizing gas and the reducing gas into the flue gas, the mixing promoting auxiliary members comprising a plurality of plate-shaped members extending in a direction perpendicular to ribs, the ribs extending between the plurality of guide vanes for disturbing the gas flow of the flue gas, and a current plate for equalizing a gas flow of the flue gas provided upstream of the reduction-denitration unit and downstream of the plurality of guide vanes, wherein the mixing unit is a spreading and swirling plate provided peripherally in the flue gas duct and formed in a flat plate shape on an upstream side in a gas flow of the flue gas in the flue gas duct and formed in a corrugated shape toward a downstream side in the gas flow of the flue gas, and the spreading and swirling plate is formed in such a way that an amplitude of the corrugated shape is increased toward the downstream side in the gas flow of the flue gas.