Method and system for treating electronic scrap smoke

Abstract

The invention discloses a method and a system for treating electronic scrap smoke. The method comprises the following steps: (1) performing countercurrent contact between smoke and absorption liquid so as to obtain purified smoke and absorbed liquid; (2) filtering the absorbed liquid so as to obtain filtrate and filter residue; (3) mixing the filtrate with a heavy metal capture agent, and performing concentration treatment so as to obtain supernatant and filter residues containing heavy metals; (4) introducing chlorine into the supernatant, oxidizing bromide ions in the supernatant into molecular bromine, so as to obtain a reaction solution containing the molecular bromine; (5) distilling the reaction solution containing the molecular bromine so as to obtain bromine-containing gas; and (6) condensing the bromine-containing gas so as to obtain a bromine product and mixed gas. According to the method, the electronic scrap smoke can be effectively purified, the purified smoke can meet the national environmental protection standard, the bromine element can be efficiently recovered, the bromine extraction rate is over 90 percent, and the purity of the bromine product is over 99 percent.

Description

technical field [0001] The invention belongs to the technical field of chemical industry, in particular, the invention relates to a method and a system for processing fume from electronic waste. Background technique [0002] Electronic waste not only contains a large amount of valuable metals (such as copper, iron, aluminum, tin, lead, etc.), but also contains precious metals (such as gold, silver, platinum, palladium, etc.), which has a high resource recovery value. However, electronic waste also contains various heavy metals such as lead, mercury, cadmium, and chromium, as well as toxic and harmful substances such as polyvinyl chloride and halide flame retardants. Improper disposal will cause serious secondary pollution to the environment. Therefore, how to effectively realize the harmless recycling of electronic waste and realize its recycling is very important for reducing environmental pressure and preventing environmental pollution, improving the reutilization rate of ...

AI Technical Summary

Problems solved by technology

The above technologies are relatively mature, but they are mainly applicable to SO in flue gas 2 Whether it is suitable for the removal of SO 2 , halogens, nitrogen-containing impurities and other complex components of electronic waste fumes, there is no relevant research

[0006] Patent 200980154308.9 discloses a solvent containing catalyst to remove sulfur-containing, nitrogen-containing (such as H 2 S, COS, CS 2 , HCN and NH 3 etc.) and halogen-containing impurities (such as HF, HCl, HBr and HI), although the impurities in the flue gas can be removed together, the separate extraction of bromine cannot be realized, and the economic benefit is poor. In addition, it contains various Impurity solvents also cannot discharge up to standard

[0007] Patent 201210007076.8 discloses a method of blowing out hot air and absorbing lye to realize desulfurization and defluorination of zinc oxide slurry. The removal efficiency of fluorine and chlorine is high. After the treatment, the direct electrolysis process of zinc oxide slurry can proceed smoothly, but there are alkalis containing halogens. It is difficult to discharge the liquid up to the standard, and the halogen cannot be recovered, and the economic benefit is poor

[0008] Patent 201310251704.1 discloses a comprehensive treatment and recycling process and device for bromine-containing high-temperature flue gas. After the waste heat boiler is cooled, the dedusting device is dedusted, and the flue gas cooling device is fully cooled, adsorbate such as modified molecular sieve, modified activated carbon, and nano-activated carbon are used in the bromine adsorption device for adsorption, and then a small amount of hot air is used to regenerate the adsorbate, resulting in high Concentrated bromine-containing gas enters the bromine condensing device to condense into liquid bromine to recover the bromine element in the flue gas, but this invention has problems such as low bromine extraction rate and unguaranteed bromine purity.

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