System for removing SO3 by spraying carbide slag slurry in coal-fired power plant

Abstract

The invention discloses a system for removing SO3 by spraying carbide slag slurry in a coal-fired power plant. The system comprises an SCR reactor, an outlet flue, a desulfurization wastewater buffertank, a carbide slag slurry tank, a carbide slag bin and an air compressor, an outlet of the SCR reactor is communicated with an outlet flue, a nozzle is arranged in the outlet flue, an outlet of thedesulfurization wastewater buffer tank is communicated with an inlet of the carbide slag slurry tank, an outlet of the carbide slag bin is communicated with an inlet of the carbide slag slurry tank, and an outlet of the carbide slag slurry tank is communicated with a liquid inlet of the nozzle. The system has the advantages that the operation cost is low, and the popularization is convenient.

Description

technical field [0001] The invention belongs to the technical field of removal of gaseous pollutants, and relates to the removal of SO by calcium carbide slag slurry jetting in a coal-fired power plant. 3 system. Background technique [0002] With the widespread implementation of ultra-low emission transformation of coal-fired power plants, SCR denitrification devices require higher denitrification efficiency. Due to boiler combustion and SCR catalytic conversion, flue gas SO 3 If the concentration is too high, it will react with the escaped ammonia produced by the excessive injection of ammonia in the SCR denitrification device, and generate ammonium bisulfate at the cold end of the air preheater, causing corrosion and blockage of the air preheater, seriously affecting the safe and economical operation of the unit. SO 3 Excessive concentration will also cause the phenomenon of "blue smoke" emitted from the chimney, causing environmental pollution and visual pollution, and...

AI Technical Summary

Problems solved by technology

[0002] With the widespread implementation of ultra-low emission transformation of coal-fired power plants, SCR denitrification devices require higher denitrification efficiency. Due to boiler combustion and SCR catalytic conversion, flue gas SO 3 If the concentration is too high, it will react with the escaped ammonia produced by the excessive injection of ammonia in the SCR denitrification device, and generate ammonium bisulfate at the cold end of the air preheater, causing corrosion and blockage of the air preheater, seriously affecting the safe and economical operation of the unit

SO 3 Excessive concentration will also cause the phenomenon of "blue smoke" emitted from the chimney, causing environmental pollution and visual pollution, and may easily lead to environmental complaints

At present, coal-fired power plants remove SO from flue gas 3 The method is mainly through the collaborative removal of existing environmental protection facilities behind the furnace (including low and low temperature dust collectors, desulfurization systems and wet electrostatic precipitators, etc.), but it cannot solve the problem of SO after SCR. 3 Air preheater blockage caused by high concentration; a few scientific research institutions have conducted pilot tests in power plants using alkaline absorbent injection technology. The alkaline absorbent uses quicklime, sodium carbonate, etc., which can effectively remove SO in flue gas 3 , but the operating cost is high and it is difficult to be widely promoted

[0003] In addition, the country has become more and more strict on water pollution control. Most coal-fired power plants require zero discharge of wastewater. The power plants need to add a new zero discharge treatment system for wastewater, which requires a large investment.

Images