Alkaline-process smoke halogen removal device and removal method

Abstract

The invention relates to an alkaline-process smoke halogen removal device and removal method. The existing boiler tail gas pipeline is not provided with a dedicated system for removing halogen, resulting in high content of halogen in desulphurization waste water. The alkaline-process smoke halogen removal device comprises a slurry preparation mechanism, an atomizing injection mechanism and a removal efficiency monitoring mechanism, wherein alkaline liquor produced by the slurry preparation mechanism is sprayed into a tail gas pipeline disposed between an air preheater and an electric dust collector by virtue of the atomizing injection mechanism, so that the fixing discharging of the halogen is realized. The halogen removal device is additionally arranged on the original tail gas pipeline, the alkaline liquor reacts with hydrogen chloride and halogen fluoride in the smoke to form solid salts, and the solids are discharged out of the tail gas pipeline by utilizing the electric dust collector, so that the halogen content in the smoke is effectively decreased, the halogen content in the desulphurization waste water is further kept at a relatively low level, not only is the operation effect of a desulphurization adsorption tower effectively improved, but also the concentration of fluorine ions and chlorine ions in the desulphurization waste water is reduced, the recycling rate of the desulphurization waste water is increased, the water consumption is reduced, and the corrosion damage of acid substances to the pipeline also can be alleviated.

Description

technical field [0001] The invention relates to the field of thermal power generation, in particular to the field of halogen removal. Background technique [0002] Halogen such as chlorine and fluorine are trace elements in coal samples, which are converted into hydrogen chloride and hydrogen fluoride gas after combustion. These gases will enter the tail gas pipeline along with the boiler exhaust gas, and then pass through the economizer and SCR (Selective Catalytic Reactor) in sequence. , AH (air preheater), ESP (electric precipitator), and FGD (desulfurization absorption tower) are discharged through the chimney. When the flue gas passes through the desulfurization absorption tower, most of the hydrogen chloride and hydrogen fluoride are absorbed and removed, and enter the desulfurization wastewater, resulting in an increase in the concentration of fluorine and chlorine in the desulfurization wastewater. When the concentration of fluorine and chlorine in the desulfurizati...

AI Technical Summary

Problems solved by technology

When the concentration of fluorine and chlorine in the desulfurization wastewater increases, it will not only affect the desulfurization effect of the wet flue gas limestone-gypsum desulfurization system in the desulfurization absorption tower, but also corrode the pipelines flowing through due to the acidity of the desulfurization wastewater, resulting in Damaged, resulting in desulfurization wastewater can not be recycled, increasing water consumption

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