Method for collecting arsenic from smelting flue gas by dry process

Abstract

The invention discloses a method for collecting arsenic from smelting flue gas by a dry process, and belongs to the field of comprehensive recycling of metallurgical waste gas. The method comprises the steps of: 1) quenching: arsenic-containing high-temperature smelting flue gas rapidly passes through a quencher for indirect cooling; 2) settling collection of arsenic: after the quenched flue gas enters a settler, white arsenic and smoke dust in the flue gas in the settler naturally settle to the bottom of the settler, and the flue gas subjected to settling is discharged from an upper flue gasoutlet, and arsenic is collected from an outlet at the bottom of the settler; and 3) electrostatic collection of arsenic: the flue gas discharged from the top of the settler enters an electrostatic demister, a small amount of residual white arsenic and smoke dust in the flue gas is collected, and the collected white arsenic and smoke dust fall into the settler. The method of the invention does notintroduce water into the flue gas, and does not reduce the dew point of the flue gas; the settler can collect dust with dew; no corrosion to equipment and pipelines are ensured; glass arsenic and thelike are prevented from blocking a bag type deduster and causing paralysis of a system; the method is applicable to smelting flue gas under different working conditions through a frequency-conversionfan; and the method can reduce sewage generated by the process.

Description

technical field [0001] The invention belongs to the field of comprehensive recovery and utilization of metallurgical waste gas, and in particular relates to a method for collecting arsenic from smelting flue gas by dry method. Background technique [0002] In the pyrometallurgy of nonferrous metals, due to the high arsenic content in the raw material ores, especially the high arsenic content in gold concentrate, copper concentrate, and lead concentrate, the flue gas after smelting contains a large amount of vaporized arsenic trioxide , has a great influence on the subsequent flue gas treatment. [0003] In the existing production, the traditional methods of collecting arsenic mainly include the following two methods: [0004] One method is quenching. Water is used to directly cool the flue gas to 120°C, so that the arsenic trioxide in the flue gas will condense into a solid phase, and then the arsenic trioxide in the flue gas will be collected by a bag filter. The disadva...

AI Technical Summary

Problems solved by technology

The disadvantage of the annular cooling method is that the gaseous arsenic trioxide will condense at 150-270°C to form glass arsenic. The arsenic trioxide of the glass arsenic structure is a very viscous substance, which will scale in the annular cooler and increase the cleaning of the annular cooler. Difficulty and frequency affect process production

In addition, due to the need to ensure sufficient cooling in the flue gas annular cooler, it is necessary to ensure that the gas velocity of the flue gas in the annular cooler is sufficiently small, so that the annular cooler will occupy a very large area and is a huge device

[0006] Therefore, for the high-temperature arsenic-containing smelting flue gas with complex working conditions, the existing two arsenic collection processes are not suitable, so it is urgent to develop a dry arsenic collection process for the treatment of smelting flue gas

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