Patent ID: 9409117
Filing Date: 2016-08-09
CPC Classification: B01D,C02F,F23J,Y02P

Claim Text:
1. An air pollution control system for a boiler that burns fuel comprising: an air heater that is provided downstream of the boiler and recovers heat of the flue gas from the boiler; a first precipitator that is provided downstream of the air heater and reduces dust in the flue gas after heat recovery; a desulfurizer that is provided downstream of the first precipitator and reduces sulfur oxides in the flue gas after dust reduction by an absorbent; a dewaterer that is connected to the desulfurizer via a waste water line and reduces gypsum from desulfurization discharged water discharged from the desulfurizer; a spray drying device that is connected to the dewaterer via a dewatering line and includes a spray nozzle for spraying dewatering filtration fluid from the dewaterer; a flue-gas introducing line that is branched from between the boiler and the desulfurizer and introduces a part of the flue gas into the spray drying device; and a water supplying line that is connected to the dewatering line and supplies water to the spray nozzle, wherein the dewatering line and the spray nozzle are cleaned by stopping the supply of the dewatering filtration fluid and supplying the water to the spray nozzle.