Technological method for leaching manganese ore with high spent acid

Abstract

The invention discloses a technological method for leaching manganese ore with high spent acid, which comprise the steps: (1) according to the technological requirements, adding sulfuric acid into manganese ore powder, so as to obtain manganese sulfate leachate after reaction; in the leachate, keeping the concentration of the sulfuric acid be (3-10)g / l; (2) adding an oxidant into the leachate for oxidation treatment; and (3) adding calcium carbonate into the leachate to react with the sulfuric acid until the pH value is within a range of 6.4 plus or minus 0.2, so as to obtain manganese ore leachate. According to the method, the concentration of leached spend acid is increased so that the manganese carbonate ore and the acid react relatively thoroughly, the leaching rate is improved, the manganese content in slag is reduced, not only is the utilization rate of resources increased, but also the pollution to the environment is effectively reduced; calcium carbonate is used for substituting for all or part ammonia water for neutralizing the spent acid, so that the problem that ammonium sulfate which is produced by using the ammonia water and the excessive spent acid is supersaturated in a circulation system is effectively solved; and the neutralization cost is greatly lowered, and obvious economic benefits are obtained.

Description

technical field [0001] The invention relates to a method for producing soluble manganese salt by dissolving manganese ore in electrolytic manganese production, in particular to a process for leaching manganese ore with excess acid. [0002] Background technique [0003] In electrolytic manganese production, the manganese ore is first dissolved, usually in sulfuric acid, to generate a soluble manganese sulfate solution. The manganese carbonate ore leaching technological process of prior art, as figure 1 As shown, according to the process requirements, add sulfuric acid to manganese ore powder for chemical reaction to generate soluble manganese sulfate solution; oxidize the leachate, mainly by adding oxidants (such as manganese dioxide, oxygen, etc.), its function is to make Fe2+ ​​is oxidized to Fe3+ to form a precipitate to remove iron ions in the solution and minimize the iron ion content in the solution; finally add ammonia water for neutralization reaction, neutralize t...

AI Technical Summary

Problems solved by technology

However, with the continuous reduction in the grade of manganese carbonate ore and the decline in the cost of sulfuric acid in recent years, this process has been difficult to meet the requirements of electrolytic manganese enterprises to pursue cost maximization; second, the leaching rate of manganese ore is relatively low, and the manganese in slag The manganese content is still relatively high, which reduces the utilization rate of resources, and the slag with high manganese content has great pollution to the environment

Third, the use of ammonia water to neutralize excessively high residual acid causes the problem of supersaturation of ammonium sulfate in the circulation system; fourth, the use of a large amount of ammonia water also increases the cost of neutralization

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