Oxidative absorption method for removing NOx and SO2 in flue gas simultaneously

Abstract

The invention discloses an oxidative absorption method for removing NOx and SO2 in flue gas simultaneously and belongs to the field of flue gas pollution control. The method comprises steps as follows: to-be-purified flue gas is introduced into a reaction device, SO2 and NOx flue gas are sufficiently contacted with an oxidative absorption solution for an oxidative absorption reaction, and finally,the flue gas is purified and discharged; the oxidative absorption solution is prepared from calcium peroxide and persulfate, and a mole ratio of persulfate to calcium peroxide in the solution is 0.15-1.5. The method for wet oxidative absorption of NOx and SO2 has strong oxidization and strong alkali absorption capabilities, and 100% SO2 removing efficiency and 70% or higher NOx removing efficiency can be realized, and the highest NOx removing efficiency even reaches 95%. With adoption of the method, NOx and SO2 in the same wet washing device can be removed simultaneously, and the method has the characteristics of being high in removing efficiency and low in cost, preventing secondary pollution and realizing recyclability of resources and the like.

Description

technical field [0001] The invention relates to a method for simultaneously removing NO in flue gas x and SO 2 The oxidation absorption method belongs to the subfield of flue gas pollution control in the field of environmental protection technology. Background technique [0002] my country's primary energy is mainly coal. With the continuous development and utilization of clean energy such as natural gas, solar energy, and wind energy, the proportion of coal demand has declined, but it still accounts for more than 60%. SO emissions from coal combustion 2 and NO x Gaseous pollutants such as gaseous pollutants can cause a series of environmental problems such as acid rain, photochemical smog, and eutrophication of water bodies. They are also the culprits of smog, which seriously endanger human health and the ecological environment. In the face of increasingly serious environmental pollution, the Chinese government has proposed that coal-fired boilers meet the emission stan...

AI Technical Summary

Problems solved by technology

Publication No. CN106731631A and Publication No. 102989273A disclose two methods that utilize chlorine-containing compounds to oxidatively absorb NO x and SO 2 Although the method can achieve a higher removal efficiency, the chlorine-containing compounds are in the removal of NO x and SO 2 Chlorine-containing gas will be produced during the process, which will cause secondary pollution to the environment. In addition, chlorine-containing oxidants will cause equipment corrosion

Publication number CN103157358A discloses a flue gas denitrification method based on advanced oxidation technology, using low-cost, non-polluting H 2 o 2 and Na 2 S 2 o 8 Composed of dual oxidants oxidatively absorb NO by active radicals generated by thermal excitation x , this method can achieve higher NO x removal efficiency, and there is no secondary pollution, but due to H 2 o 2 The instability of will cause invalid decomposition, so that H 2 o 2 Utilization is low, and when H 2 o 2 Explosive in overdose