Three-stage flue gas low-temperature combined desulfurization and denitrification system and method thereof

Abstract

The invention relates to a three-stage flue gas low-temperature combined desulfurization and denitrification system and a method thereof, one end of a desulfurization reactor is communicated with a flue gas cooler, and the other end of the desulfurization reactor is sequentially communicated with a demister, a carbon-based adsorbent pretreatment reactor, a flue gas reheater and a denitrification reactor in the flue gas inflow direction. According to the three-stage flue gas low-temperature combined desulfurization and denitrification system and method provided by the invention, flue gas is subjected to graded synergistic desulfurization and denitrification after being cooled, so that the problem of high-temperature ignition is avoided, the NO adsorption performance of a carbon-based adsorbent is improved, the desulfurization effect of the carbon-based adsorbent is greatly improved, and the SO2 removal efficiency in the first-stage reactor reaches 99% or above; the adverse effect of SO2on NO removal in the downstream reactor is avoided, the risk that the generated NH4HSO4 blocks the surface pores of the carbon-based adsorbent is reduced, the NO removal rate in the third-stage reactor achieves more than 90%, the efficient desulfurization and denitrification is achieved while the partial pollutants such as heavy metals, VOCs and the like can be synergistically removed, the structure is simple, and the application prospect is broad.

Description

technical field [0001] The invention belongs to the technical field of flue gas desulfurization and denitrification, and in particular relates to a three-stage flue gas low-temperature combined desulfurization and denitrification system and method. Background technique [0002] As my country's power industry undergoes continuous ultra-low emission transformation, the total amount of pollutant emissions continues to decrease. At present, pollutants emitted by non-electric industries such as metallurgy are the key targets of air pollution control. In addition to requiring SO 2 , NO and other pollutant gas discharge standards at the same time, but also require enterprises to eliminate white gas flue gas. At present, the flue gas whitening technology of enterprises generally adopts the method of cooling and condensing the flue gas first, and then heating the flue gas. [0003] Activated carbon / coke / carbon fiber (for convenience of description, hereinafter referred to as carbon-...

AI Technical Summary

Problems solved by technology

Both Chinese patent CN102019135A and Chinese patent CN209865768U are equipped with two-stage reactors, and in the first-stage reactor, NH 3 easy with h 2 SO 4 form highly viscous NH 4 HSO 4 , to block the pores on the surface of the catalyst in the reactor, resulting in rapid deactivation of the catalyst; on the other hand, high smoke temperature will cause high carbon loss of the carbon-based adsorbent, increasing the loss of the adsorbent

At the same time, there is a risk that the local smoke temperature reaches the ignition point and a fire occurs

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