Integrated technology of wet flue gas desulfurization and denitrification

2017-10-9 16:17:45

The process of simultaneous desulfurization and denitrification of wet flue gas usually oxidize no to NO2 at the gas / liquid phase, or increase the solubility of no by adding additives. Wet simultaneous desulfurization and denitrification methods are mostly in the research stage, including oxidation and wet complexing.

Oxidation method:

1, chlorate oxidation process is a wet washing system, in a set of equipment to remove sulfur dioxide and nitrogen oxides in flue gas. Tri-nox-noxsorb process uses two stages of oxidation absorption tower and basic absorption tower to remove toxic trace metals, such as as, be, CD, Cr, Pb, Hg and Se, in the removal of sulfur dioxide and nitrogen oxides.

2, yellow phosphorus oxidation is the oxidation of no to NO2, the absorption slurry reaction of sulfate and nitrate and alkaline liquid, the sulfur dioxide and nitrogen oxide removal rate reached more than 95%, but the yellow phosphorus have flammable, instability and some toxicity. The pretreatment method needs to solve these problems.

Wet complexing absorption process:

In the wet complex absorption process, iron or cobalt is used as the catalyst, and complexing agent no can be added into the aqueous solution to make it into a complex. No combined with complexing agent can react with so32-/hso3- in the solution to form a series of N-S compounds and regenerate the complexing agent. The process involves regeneration of the absorption solution by removing two sulfate, sulfate and N-S compounds, and ferric chelates into ferrous chelates by absorption from the absorption solution.

Wet complexing absorption process can simultaneously desulfurization and denitrification, but it is still in the experimental stage. The main obstacle to its industrial application is that the loss of chelates and the difficulty in the regeneration of metal chelates and the low utilization rate in the process of reaction are the problems of high operating costs.