The treatment of waste gas from power plants generally requires consideration of the following two aspects:
Flue gas desulfurization and denitrification treatment
Fuels commonly used in power plants, such as coal, etc., are produced after combustion. Exhaust gases contain harmful gases such as SO2 and NOx. In order to meet emission standards, exhaust gases must be desulfurized and denitrified.
Desulfurization treatment mainly adopts two methods: wet flue gas desulfurization and dry flue gas desulfurization, among which wet flue gas desulfurization is the most commonly used. It mainly uses absorbents, such as limestone or ammonia, to react the SO2 present in the flue gas with the absorbent to generate calcium sulfate or sulfatee of ammonium and other substances, thereby achieving the goal of desulfurization.
Denitrification treatment mainly adopts two methods: selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR). SCR converts NOx into nitrogen and water by injecting ammonia into the flue gas and reacting the ammonia with the NOx. The SNCR injects reducing agents such as urea and ammonia into the flue gas to reduce NOx to nitrogen and water at high temperatures.
Fume dust removal treatment
The flue gases from power plants also contain a large amount of dust. In order to meet emission standards, dust removal treatment is necessary.
There are two main methods of flue gas dust collection: the electrostatic precipitator and the bag dust collector. Among them, the electrostatic precipitator uses a fieldhigh-voltage electric to adsorb charged particles to achieve the purpose of dust removal; while the bag dust collector uses filter bags to capture dust particles in the flue gas to achieve the dust removal objective.
It should be noted that the treatment of waste gas from power plants should take corresponding technical measures based on specific conditions and should comply with relevant environmental protection regulations and standards. For some more complex waste gas compositions, various technical means may be required to treat them.