Method for treating flue gas containing SO2 using red mud

Abstract

The invention relates to a method for processing SO2-containing smoke gas by utilizing red mud, and is characterized in that the red mud is modulated into red mud pulp and added in a reaction tank provided with a churn-dasher; acid-base neutralization reaction is performed between the red mud and SO2 that is pumped in the smoke gas in the reaction tank; when the red mud pulp is approximately acid, all the red mud pulp is discharged and sent for filter and separation; new red mud pulp is replenished to the reaction tank at the same time; sodium sulfate can be recovered from the obtained filter liquor through evaporation and crystallization; filter residue can be directly used as cement raw material or rehabilitation backfill soil in a mine; the content of the SO2 in tail gas is less than 400mg / Nm<3>, and is less than the national standard limit. The desulfurizer that is the red mud used in the method is aluminum industrial scrapped parts, the source is rich, the cost is low, and the red mud is easy to obtain; the desulphurization principle is acid-base neutralization; the red mud has strong absorptive capacity to the SO2, and the desulphurization effect is good; the modification treatment of the red mud is realized when in desulphurization, and the purpose of waste control by waste and comprehensive utilization.

Description

A method of using red mud to treat flue gas containing SO2 technical field The invention discloses a method for treating flue gas containing SO2 by using red mud, and relates to a method for utilizing solid waste in the aluminum industry and treating flue gas containing SO2. Background technique The impact of "acid rain" on the environment is becoming more and more serious. "Acid rain" is mainly formed by the reaction of SO2 discharged into the atmosphere with water. With the rapid development of the aluminum industry and the continuous expansion of production capacity, the emission of flue gas containing SO2 increases year by year, which is harmful to the surrounding environment. The SO2 flue gas in the aluminum industry mainly comes from the combustion of sulfur-containing fuels, the calcination of petroleum coke and the consumption of carbon anodes. In the past, the SO2-containing flue gas treatment technology mostly used the lime / limestone-gypsum method. The essence ...

AI Technical Summary

Problems solved by technology

However, the lime / limestone-gypsum method has the following disadvantages: (1) Due to the use of milk of lime as the absorbent, the particle size of the calcium compound is very high, resulting in high grinding costs; High cost; (3) After desulfurization, a large amount of desulfurization wastewater is generated, which cannot be discharged up to the standard, and the desulfurization wastewater needs to be treated, which increases the cost of desulfurization

However, this technology has the following technical problems: (1) The red mud slurry is unstable and easily stratified; (2) The red mud slurry is difficult to spray, and the fine red mud particles can easily block the nozzles and spray pipes, causing operational difficulties

The above-mentioned technical difficulties limit the industrial application of this method