Treatment method and device for incineration arsenic-containing flue gas

Abstract

The invention discloses a treatment method and device for incineration arsenic-containing flue gas. The treatment method comprises the following steps: the incineration arsenic-containing flue gas ofwhich the temperature is higher than 313 DEG C is introduced in a ceramic tube dust collector for dust collection, the flue gas after dust collection enters a mixing chamber, liquid nitrogen is introduced in the mixing chamber, and is in reverse contact with the flue gas to reduce the temperature of the flue gas to 30 DEG C, part of arsenic trioxide particles separated out through temperature reduction are sedimentated to the bottom of the mixing chamber to be discharged, the rest of arsenic trioxide particles enter an electric dust collector along with the flue gas to complete collecting, andthe flue gas after arsenic removal is directly discharged. A large amount of heat is absorbed through vaporization of liquid nitrogen, and the solidification range of amorphous arsenic trioxide is quickly crossed, so that crystal form arsenic trioxide is obtained to the maximum limit; liquid nitrogen entering the flue gas does not react with a gas component, and the chemical property of the gas component is not changed; arsenic is collected with electricity and is only removed; and no water is used in the whole process, so that water consumption and the subsequent water treatment cost are reduced greatly, an industrial arsenic trioxide product is produced, and environmental benefits and social benefits are improved.

Description

technical field [0001] The invention relates to a treatment method and device for incinerating arsenic-containing flue gas, belonging to the technical field of environmental engineering. Background technique [0002] In order to implement the "Opinions on Accelerating the Promotion of Ecological Civilization" proposed by the Party Central Committee, the Agriculture Bureau of Huanjiang Maonan Autonomous County in Guangxi introduced the planting technology of centipede grass, which rapidly extracts, concentrates and enriches arsenic in the soil during the growth process of centipede grass. Remediate the soil by regularly harvesting centipede grass to remove arsenic from the soil. According to the introduction of the Bureau of Agriculture, centipede grass will be incinerated, and the flue gas will be treated by "quick cooling + wet dust removal + bag dust removal" device; the ash contains high concentration of arsenic, and it will be landfilled as hazardous waste. [0003] Low...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to provide a treatment method for incinerating arsenic-containing flue gas, which solves the problems such as the large amount of sewage generated by the wet arsenic removal process and the secondary pollution caused by the generation of mud arsenic. The arsenic-containing flue gas from incineration at 313°C is passed into a ceramic tube dust collector to remove dust. After dust removal, the flue gas enters the mixing chamber, and at the same time, liquid nitrogen is passed into the mixing chamber. The liquid nitrogen and the flue gas are in reverse contact to reduce the flue gas temperature to 30°C. After that, part of the arsenic trioxide particles precipitated by cooling down will settle to the bottom of the mixing chamber and be discharged, and the other part of the arsenic trioxide particles will enter the electrostatic precipitator along with the flue gas to complete the collection, and the flue gas will be discharged after arsenic removal.

Images