Coal-fired flue gas demercuration method employing additive and adsorbent

Abstract

The invention discloses a coal-fired flue gas demercuration method employing an additive and an adsorbent. The additive is one of or a mixture of more or bromine compounds, wherein the bromine compounds comprises NaBr, KBr, NaBrO3, KBrO3 and CaBr2 aqueous solutions, the concentrations of which are separately 0.1-5mol / L, 0.1-3mol / L, 0.1-1mol / L, 0.1-1mol / L and 0.1-5mol / L; the adsorbent is one of or a mixture of more of active carbon, active coke and Br-carrying modified active carbon, wherein the Br-capacity of the Br-carrying modified active carbon is 1-10wt%. The additive is added into a boiler of a coal-fired glue gas combustion system and the adsorbent is sprayed on an upstream flue of a dedusting device of a flue gas purification system. The synergistic demercuration action of the method is maximized, and the existing pollutant removal equipment can be utilized, so that the coal-fired flue gas demercuration method has the advantages of simple process, high demercuration efficiency, low cost and the like.

Description

technical field [0001] The invention belongs to the field of energy saving and environmental protection, in particular to a coal-fired flue gas mercury removal method using additives and adsorbents in the field of air pollution control. Background technique [0002] With the development of the economy, the consumption of energy such as coal and oil continues to intensify. The combustion and utilization of these fuels will produce SOx, NOx, dust, mercury and many other air pollutants. After entering the human body through food, diet and other ways, it will cause various diseases of the nervous system and cardiovascular system, which will cause great harm to human health. In my country, coal-fired power plants, coal-fired industrial boilers, non-ferrous metal smelting, and cement industry are the main sources of mercury emissions, accounting for more than 80% of mercury emissions in the entire industry, most of which are emitted by coal-fired power plants and industrial boiler...

AI Technical Summary

Problems solved by technology

However, although the modified adsorbent can strengthen the adsorption of mercury in flue gas, its main adsorption object is Hg 2+ or Hg p , while for Hg 0 There are still limitations in the enhanced adsorption capacity of

[0006] It can be seen that although the single technologies currently in commercial use such as mercury oxidation absorption or adsorption mercury removal can increase the mercury oxidation rate or the mercury adsorption capacity, they have not been integrated into the mercury system control according to their removal mechanism. If effective Coupling these two technologies, on the one hand, the previously oxidized mercury is absorbed by the adsorbent to avoid a large amount of mercury being absorbed by the liquid phase and then released again; Effectively coupling these two technologies is not a simple arithmetic summation, it not only improves the overall mercury removal efficiency, but also reduces the amount of oxidant and adsorbent correspondingly, reducing the cost

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