Two-stage ammonia leaching-flow distributing extraction method for copper oxide ore

Abstract

The invention discloses a two-stage ammonia leaching-separation extraction method for copper oxide ore, which is used for treating refractory copper oxide ore with high alkaline gangue content, first dry-grinding the raw ore, and then immersing with concentrated ammonia The liquid is subjected to the first stage of stirring and leaching under normal temperature and pressure sealed conditions, and the first stage of solid-liquid separation; Solid-liquid separation, followed by washing and solid-liquid separation; then the concentrated ammonia leaching solution, medium ammonia leaching solution and dilute ammonia leaching solution are introduced into the split extraction system, and copper is stripped back, and copper ions are enriched into the back-extracted aqueous rich solution In the process, raffinates with different ammonia concentrations can be obtained for recycling, that is, the two-stage ammonia leaching-split extraction of copper oxide ore is completed. The invention has the advantages of increasing the leaching rate of copper, reducing volatilization and dilution of ammonia for circulation, improving industrial sanitation conditions, and reducing the efflux loss of copper in residual water taken away by leaching slag.

Description

technical field [0001] The invention relates to a method for leaching materials with ammonia, in particular to a two-stage ammonia leaching-separation extraction method for treating refractory copper oxide ore with high alkaline gangue content, and belongs to the technical field of mineral treatment. Background technique [0002] For the refractory copper oxide ore with high alkaline gangue content, if it is treated by flotation, it will be disturbed by the slime, which will cause a large consumption of chemicals and a low recovery rate; However, the ammonia leaching method at room temperature and pressure has the characteristics of good leaching selectivity, no consumption of chemicals for gangue, and less impurities in the leachate. [0003] For the refractory copper oxide ore containing high alkaline gangue, the free copper oxide in the raw ore can be recovered first by direct ammonia leaching at normal temperature and pressure. -Extraction-electrodeposition-leach slag f...

AI Technical Summary

Problems solved by technology

[0007] According to the existing wet grinding method, the wet grinding system and the slurry blending system are integrated. If the ammonia is not steamed back to the liquid, and the system is to avoid water expansion and cause the loss of ammonia to the outside, it must be suitable The concentrated ammonia immersion solution required for leaching is added to the wet grinding system, but the wet grinding equipment and spiral classifying equipment of this system are difficult to seal, and the ammonia will be volatilized and lost; the wet grinding also makes the pulp heat up, which intensifies the ammonia Volatile

In this way, not only more ammonia needs to be added before leaching, which increases the production cost, but also the volatilized irritating ammonia smell also deteriorates the industrial hygiene conditions of the production workshop

The way to improve is to cover the grinding and grading equipment, and then set up another fan to pump the tail gas to the absorption tower, but the absorption efficiency of ammonia is not high after it is diluted by air

[0008] According to the existing single-stage ammonia leaching process, when the ammonia leaching reaction is carried out to a certain extent, the dissolved copper ions will hinder the continuation of the reaction, which is not complete for the leaching of free copper oxide; moreover, after the single-stage ammonia leaching The solid-liquid separation, the water content of the filter residue is 12-15%, which brings 4-8% concentrated ammonia leaching liquid into the washing operation

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