Copper ore acid leaching -replacement (precipitation)-flotat
2020-09-30 11:17Introduction：Copper ore acid leaching - replacement (precipitation) - flotation process (LPE process ) The acid leaching-displacement flotation processis called LPE process, which consists of three stages: the first stage is the oxidation and mixed cop
Copper ore acid leaching -replacement (precipitation)-flotation process (LPE process)
The acid leaching-displacement flotation process is called LPE process, which consists of three stages: the first stage is the oxidation and mixed copper ore leaching with dilute sulfuric acid solution, the second stage is the replacement leaching solution of iron chips, the other is copper replacement precipitation, and the third stage is flotation precipitation of copper.
The process engineering of this process can be summarized as follows:
2. Leach out. The suitable conditions, such as the concentration of sulfuric acid, the ratio of ore slurry to solid, and the temperature, should be determined by experiments. Generally speaking, dilute sulfuric acid with concentration of 0.5 ~ 3% is used as leaching agent to decompose the secondary copper oxide mineral. The residual acid is generally 0.05 ~ 0.1%and the ratio of solid to liquid is 1: (1~2). Leaching takes place at room temperature or to heat to50~80℃.
3. Precipitate. Scrap iron, iron chips, spongy iron or burnt waste cans can be used as precipitators, or hydrogen sulfide can be used as precipitator to precipitate copper in sponge or copper sulfide form. The pH value and the amount of precipitator were mainly controlled during precipitation. The ratio of solid to liquid is 1: 3, the initial acidity is 2 ~ 3 g / l, the replacement time is 10 ~ 25 min, the deposition of copper is 87 ~ 97% and the iron consumption is mainly determined by the residual acidity of the medium, which is generally 1.2 ~ 3.5kg / kg. When replacing the precipitate, avoid inflating to avoid oxidizing and remelting the replacement copper. If the residual acid in the leachate is too high, it can be neutralized with lime.
4. Flotation. Metal copper has good floatability. The flotation of precipitated copper is carried out directly in weak acid (pH=3.7~4.5) pulp. Cresol black and mixed with cresol (1:1) and double dixanthate are generally used as collector, cresol or turpentine as foaming agent, and cresol or turpentine as foaming agent. Undecomposed copper sulphide floats with associated precious metals and precipitated copper. Flotation process is simple, usually from rough separation tank can produce rich concentrate.
In a word, the process can be characterized by fine grinding fineness, dilute leaching agent, leaching slurry without solid-liquid separation, and undecomposed copper sulphide and precious metals can be recovered by flotation with precipitation. Higher grade and recovery of copper concentrate can be obtained compared with direct flotation process.
