With the vigorous efforts of the state to strengthen environmental protection, the emission standards of air pollutants are becoming more and more stringent. According to the National Development and Reform Commission, the Ministry of Environmental Protection, the National Energy Administration jointly formulated the "Coal electricity energy conservation and emission reduction upgrade and transformation plan (2014-2020)," the concentration of air pollutants in key areas basically reached the gas turbine group emission limits. Ultra-low emission standards stipulate that the content of soot should not be higher than that of 10mg/Nm, the content of sulfur oxides should not be higher than that of 35mg/Nm, and the concentration of nitrogen oxides should not be higher than that of 50mg/Nm.
Flue Gas Desulfurization (FGD) system: the denitrification system mostly adopts the combination of low NOx burner and SCR catalyst. This kind of system is mature in technology and reliable in operation. The coal-fired power station with super emission is compared with the conventional power station. The main difference of denitrification system is the number of filling layers of SCR catalyst. The original 2 + 1 (2 layer filling, 1 layer standby) layer catalyst can be directly changed to 3 layers of SCR catalyst, if necessary, 4 layers of SCR catalyst can be used in the revamping project. After revamping, the denitrification efficiency of the system can be increased to more than 90%, which can meet the requirements of NOx < 50mg/Nm.
Flue gas denitrification system: for newly built units, it is possible to adopt flue gas uniform distribution device (retrofitting on the basis of the original absorption tower without changing the diameter and height of the absorption tower and the volume of the slurry pool of the absorption tower, and without increasing the circulation pump; The desulphurization efficiency can reach above 981.99% by adding flue gas uniform distribution device, which can meet the requirement of ultra-low emission sulfur dioxide < 35mg/Nm.
Flue gas dedusting system: five electric field low temperature electrostatic precipitator, five electric field rotating plate electrostatic precipitator, high frequency electrostatic precipitator, high efficiency dedusting and desulphurization device, wet electrostatic precipitator can be chosen. It can meet the emission requirements of ultra-low emission PM < 5mg/Nm, etc.