Hydrochloric acid purification system and process

Abstract

The invention discloses a hydrochloric acid purification system and process. The purification system comprises a dechlorination device, an iron removal device and a recovery tank which are connected in sequence. The dechlorination device comprises a dechlorination tank body, the dechlorination tank body is filled with activated carbon, a dechlorination liquid inlet and a dechlorination liquid outlet are formed in the top and the bottom of the dechlorination tank body respectively, and the dechlorination liquid inlet is used for guiding hydrochloric acid into the dechlorination tank body; the iron removal device comprises an iron removal tank body, the iron removal tank body is filled with resin, an iron removal liquid inlet and an iron removal liquid outlet are formed in the top and the bottom of the iron removal tank body respectively, the iron removal liquid inlet and the chlorine removal liquid outlet are connected through a pipeline, and a first filter is arranged on the pipeline; and the recovery tank is connected with the iron removal liquid outlet through a pipeline, and a second filter is arranged on the pipeline. The system disclosed by the invention can effectively remove free chlorine and iron under the condition that the concentration of hydrochloric acid is not obviously reduced.

Description

technical field [0001] The invention relates to the technical field of waste gas treatment, in particular to a hydrochloric acid purification system and process. Background technique [0002] At present, the main method of treating chlorine-containing organic waste is thermal decomposition technology, including incineration, cracking, gasification and other technologies. This technology can reduce, harmless and recycle pollutants in a short time. Through incineration, highly toxic chlorine-containing organic waste decomposes inorganic substances such as carbon dioxide, water, hydrogen chloride, chlorine and a small amount of nitrogen oxides. [0003] If the HCl in the incineration flue gas is discharged directly without treatment, it will seriously pollute the environment, and if the HCl is not recycled, it is also a waste of resources. Using lye to directly absorb HCl, although the consumption of alkali is small and the cost is low, it will cause secondary pollution to the...

AI Technical Summary

Problems solved by technology

However, the hydrochloric acid recovered by this method is poor in quality and contains impurities such as free chlorine and iron ions, wherein free chlorine is a yellow-green toxic elemental gas, which is insoluble in water and has a suffocating odor. Chlorine gas should not exceed 0.001mg / L, and after high-temperature incineration, and in a high-chloride ion system, iron ions mainly exist in the form of ferric ions and ferric tetrachloride complex ions. Therefore, the hydrochloric acid solution obtained by water absorption requires Purified before recycling

[0004] Regarding the purification method of hydrochloric acid in the HCl recovery unit in the incineration flue gas, there are no systematic research reports at home and abroad.

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