Process Introduction
The main component of NOx in flue gas is NO (accounting for 95%), which is difficult to dissolve in water, while high-valent NO2, N2O5, and other substances can be dissolved in water to generate HNO2 and HNO3, greatly improving the solubility, which can be absorbed simultaneously with SO2 in the later stage, achieving the goal of simultaneous desulfurization and denitrification. As a clean and strong oxidant, ozone can quickly and effectively oxidize NO to a high valence state. The life cycle of O3 is relatively long. After ionizing oxygen or air, O3 is generated, which is then sent into the flue gas, effectively removing NOx from the flue gas.
Process Principle
The oxidation ability of ozone is extremely strong. From the table below, it can be seen that the oxidation and reduction potential of ozone is second only to fluorine and higher than hydrogen peroxide and potassium permanganate. In addition, the reaction product of ozone is oxygen, so it is a highly efficient and clean strong oxidant.
NO+O3→NO2+O2 （1）
NO2+O3→NO3+O2 （2）
NO3+NO2→N2O5 （3）
NO+O+M→NO2+M （4）
NO2+O→NO3 （5）
Ozone denitrification mainly uses the strong oxidizing property of ozone to oxidize NO into high valent nitrogen oxides, and then absorbs and converts the nitrogen oxides into water soluble substances in the scrubber to achieve the purpose of removal. At typical flue gas temperatures, the oxidation efficiency of ozone for NO can reach over 95%. Combined with wet tail washing, the denitrification efficiency also reaches 98% when the O3/NO molar ratio is 1.
Technical Advantages
1. High denitration efficiency, low investment and operation costs, with denitration efficiency up to 100%
2. Compared with traditional processes, the reaction temperature is lower and the reaction speed is faster
3. No need for special supporting reactors, no need for catalysts, and no increase in system resistance
4. Adding ozone will not cause additional corrosion to the system flue and equipment, and will not affect the thermal efficiency of the system
5. The system is simple and stable in operation, with minimal impact from operating conditions, only related to reaction temperature and dosage
2. Compared with traditional processes, the reaction temperature is lower and the reaction speed is faster
3. No need for special supporting reactors, no need for catalysts, and no increase in system resistance
4. Adding ozone will not cause additional corrosion to the system flue and equipment, and will not affect the thermal efficiency of the system
5. The system is simple and stable in operation, with minimal impact from operating conditions, only related to reaction temperature and dosage
Performance Index
Denitration efficiency up to 100%