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

Abstract

The invention discloses a two-stage ammonia leaching-flow distributing extraction method for a copper oxide ore, which is used for processing the refractory copper oxide ore rich in basic gangue. The method comprises the following steps: firstly, dryly milling a raw ore, performing first-stage stirring leaching under the normal pressure, normal temperature and airtight conditions by using a strong ammonia leaching solution, and performing first-stage solid-liquid separation; performing second-stage stirring leaching under the normal pressure, normal temperature and airtight conditions by using a neutral ammonia leaching solution, performing second-stage solid-liquid separation, washing and performing solid-liquid separation; and introducing the strong ammonia leaching solution, the neutral ammonia leaching solution and a dilute ammonia washing solution into a flow distributing extraction system, back extracting copper, enriching copper ions into a back extracting water-phase pregnant solution, thereby obtaining reusable raffinates with different ammonia concentrations, and finishing the two-stage ammonia leaching-flow distributing extraction for the copper oxide ore. The two-stage ammonia leaching-flow distributing extraction method for the copper oxide ore has the advantages that the leaching efficiency of copper is increased, the volatilization and dilution of the reusable ammonia are reduced, the industrial hygiene condition is improved, and the effluent loss of the copper taken away from the remained water by leaching slag is reduced.

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

Images