A Synergistic Removal Process of Flue Gas Pollutants Using Complexation Absorption and Synchronous Electrolytic Reduction

Abstract

The invention discloses a synergistic removal process of flue gas pollutants through complexation absorption and synchronous electrolytic reduction. The technical solution includes that the flue gas is pressurized and sent to the concentration tower for reaction, and the flue gas exiting the concentration tower is sent to the absorption tower and the circulating absorption liquid sprayed from the upper spray layer of the tower is reversely contacted and reacted, and then discharged from the top of the absorption tower; the concentration tower The concentrated liquid at the bottom is sent to the ammonium sulfate crystallization system after iron removal; the circulating absorption liquid sprayed out from the spray layer contacts and reacts with the flue gas reversely, and then enters the bottom of the absorption tower through the electrolytic regeneration layer below the flue gas inlet. The electrolytic regeneration layer is a cathode layer, an anode layer, and a cathode layer from top to bottom; the electrode layer is a mesh structure made of conductive materials, and two adjacent electrode layers are insulated from each other; the electrolytic regeneration layer is installed on The terminal on the tower wall is connected with the power supply. The invention has the advantages of simple process, high reaction efficiency, low operating and investment costs, and small occupied area, and is especially suitable for the coordinated treatment of multi-pollutants in flue gas.

Description

technical field [0001] The invention relates to a flue gas treatment process, in particular to a synergistic removal process of flue gas pollutants through complexation absorption and synchronous electrolytic reduction, especially suitable for sulfur dioxide, nitrogen oxides, fine particles, dioxins, etc. in flue gas Collaborative governance of multi-pollutants. Background technique [0002] There are many types of flue gas desulfurization and denitrification technologies, and the engineering application of individual desulfurization or denitrification technologies is becoming more and more perfect. However, the application of multi-pollutant collaborative control technology for flue gas is less. At present, apart from the relatively mature adsorption method, other collaborative control technologies for engineering applications, especially the multi-pollutant collaborative control technology of flue gas wet method, have not been reported yet. Wet flue gas synchronous desul...

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Problems solved by technology

[0004] On the one hand, there are following problems in adopting the iron filings method in the regeneration step: (1) Since the absorption liquid is acidic, the iron filings are easily corroded, resulting in a large consumption of iron filings, and the concentration of iron ions in the absorption liquid is too high, which increases the efficiency of iron removal. The cost also affects the quality of desulfurization and denitrification by-products; (2) Since the elemental iron in the iron filings is oxidized and corroded into the solution, the pH value of the absorption solution increases, resulting in the weakening of the regenerative reduction ability of the iron filings to the complexing agent

In order to ensure the denitrification efficiency, acid needs to be added to the system, resulting in a further increase in denitrification costs

(3) The consumption of iron filings is relatively large, and a large amount of elemental iron is oxidized into the absorption liquid. Since the pH value of the absorption liquid is controlled above 5.0, the absorption liquid contains a large amount of ferric hydroxide colloid (suspended matter), which will lead to circulation The wear of the impeller of the pump is increased, and it will also cause the nozzle and pipeline to block

(4) Since iron filings are filled in the closed regeneration tower, and the consumption of iron filings is continuous, continuous replenishment of iron filings cannot be realized

[0010] (1) The area where the electrolyte of the existing electrochemical reaction process enters the reactor is the area surrounded by the cathode, the anode, and the shell of the reactor. When leaving the reactor, the electrolyte flows out from the cathode chamber and the anode chamber respectively, and the reactants The conversion rate is low, the highest will not exceed 50%

[0011] (2) For the reaction system with good electrochemical reversibility between the reactant and the product, the existing electrolysis device will cause repeated conversion between the reactant and the product in the electrolytic iron removal reactor, which affects the conversion efficiency , and waste power consumption;

[0012] (3) The existing electrolysis device cannot effectively use the flow of the electrolyte itself to provide a large turbulent force for rapid renewal of the reactants on the electrode surface, and the electrochemical reaction speed is relatively slow, thereby reducing the reaction conversion rate;

[0013] (4) For complex reaction systems containing side reactions, existing electrolysis devices cannot effectively remove electrochemical reaction products that cause side reactions in a timely manner;

[0014] (5) The existing electrolysis device has a complex structure and a large footprint

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