Harmless treatment method of electrolytic manganese residue

Abstract

The invention relates to a harmless treatment method of electrolytic manganese residue. The method comprises the following steps of: (1) putting fresh electrolytic manganese residue into a mixer, adding sodium phosphate in a stirring state, and evenly stirring, wherein the mass ratio between the sodium phosphate and the dry electrolytic manganese residue is 3-5%; (2) adding calcium oxide in a continuously stirring state, evenly stirring, and continuously recovering ammonia gas generated in the stirring process, wherein the mass ratio between the calcium oxide and the dry electrolytic manganese residue is 5-10%; (3) unloading when the ammonia gas does not overflow from a mixture obtained in the step (2) to obtain the mixture after harmless treatment. The method not only can effectively fix soluble manganese left in the electrolytic manganese residue, but also can treat residual ammonia nitrogen and other impurities in the electrolytic manganese residue at the same time, thus being very beneficial to resource utilization. The method also has the advantages of being low in treatment cost and easy to operate.

Description

technical field [0001] The invention relates to a method for harmless treatment of electrolytic manganese slag. Background technique [0002] Electrolytic manganese slag is an industrial waste produced during the production of manganese metal by electrolysis. When they are just filtered out from the electrolytic tank, the water content in terms of mass is as high as 25-30% (therefore, it is called "fresh electrolytic manganese slag" in the present invention to distinguish it from anhydrous dry electrolytic manganese slag). manganese slag). The waste residue is weakly acidic and complex in chemical composition; it includes residual soluble manganese (Mn) and ionic NH 4 + form of ammonia nitrogen. If such electrolytic manganese slag is piled up, soluble manganese and ammonia nitrogen will be gradually transferred to the surrounding soil, groundwater and rivers under the erosion of rainwater, which will cause great pollution to the environment—not only causing excessive hea...

AI Technical Summary

Problems solved by technology

This prior art has indeed achieved better technical effects. However, this prior art cannot simultaneously fix or process the ammonia nitrogen in the electrolytic manganese slag, and the harmless treatment of the electrolytic manganese slag is not thorough enough.