Desulfuration process for chromate waste water

Abstract

The invention relates to the processing of an industrial three-waste product, in particular to a desulfuration process for chromate waste water, which comprises the following steps: sulfur tail gas is cooled and washed after being dedusted firstly; the pH value of the chromate waste water is adjusted to 2 to 3; the sulfur tail gas and the chromate waste water react in an absorption tower; alkali liquor and flocculating agent is added in reacted liquid in the absorption tower and then chromium hydroxide is separated out through deposition; and the tail gas which comes from the absorption tower is desulfurized thoroughly through a double alkali method. Proven by a test, the processing process of the chromate waste water is simple, so that the chromate waste water pollution and sulfur waste gas pollution can be solved simultaneously merely through one process, the device investment is less, the energy consumption is low, and the national requirements of energy conservation and emission reduction can be met; and moreover, the process is adaptable, so that both high-concentration chromate waste water and low-concentration chromate waste water can be processed.

Description

technical field [0001] The invention relates to the treatment of industrial "three wastes" products, in particular to the desulfurization process of chromium-containing wastewater. Background technique [0002] Chromium-containing wastewater usually refers to the 6+ For chromium salt production enterprises, it mainly comes from the leaching water of chromium slag and the flushing water of the production site, as well as the wastewater of some workshops. The discharge of these wastewater is huge, of which Cr 6+ content is also quite large. Due to Cr 6+ It can be enriched in animals and plants and will seriously endanger human health, so it is necessary to control 6+ Effective treatment of waste water. According to the national environmental protection law, Cr in the discharged water 6+ < 0.5 mg / L, compared with this standard, Cr in waste chromium water from all chromium salt production enterprises 6+ All exceed the standard stipulated by the state, so the treatment o...

AI Technical Summary

Problems solved by technology

[0004] In existing Cr containing 6+ In the wastewater treatment process, the distillation concentration method has very limited treatment capacity and poor adaptability, and is only suitable for treating Cr-containing waste with high concentration and few impurities. 6+ Cleaning water, for a large amount of Cr 6+ Wastewater with a relatively low concentration cannot be treated. The equipment investment of the ion exchange method is large, the process is complicated, and the consumption of resin and acid and alkali is large, while the technology of electrodialysis and reverse dialysis is difficult to master and consumes a lot of energy.

In addition, the treatment of sulfur-containing flue gas is also a large investment in environmental protection for enterprises, and it is usually necessary to set up a separate flue gas treatment section