Beneficiation of non-ferrous metal ores

The objects for enrichment processes are, as a rule, solid minerals extracted from the subsoil or from the surface of the earth.

As a result of enrichment, the following occurs:

• the concentration of the valuable component increases tens, hundreds of times;
• removal of harmful impurities from concentrates, which facilitates metallurgical or other subsequent processing;
• reduction of transportation costs for the consumer;
• increasing the productivity of subsequent processing, reducing fuel and electricity consumption, reducing losses of valuable components

The feasibility of enrichment before metallurgical processing is shown in Table 1.

The same thing happens when smelting copper, zinc, tin concentrates. In addition, ores are usually polymetallic and to carry out smelting it is necessary to separate the concentrates at the enrichment stage, for example, if lead concentrate contains a lot of zinc, then it cannot be extracted by the usual metallurgical method.

Non-ferrous metal ores have a number of characteristic features that determine not only the choice of technology for their processing and enrichment, but also the technology for developing deposits. Development of deposits is complicated by the need to issue ores by technological grades. Industrial types of ores are distinguished by the content of the main and associated components, as well as by the shape of the ore bodies and genesis. The different nature of mineralization of the ores being processed requires the development of a more advanced technology for ore preparation and the use of more complex stage enrichment schemes. The optimal final and intermediate (by stage) grinding size is selected based on the dependence of the enrichment indicators on the ore size. Conventionally, a distinction is made between coarse (45-55%, i.e. - 0.074 mm), medium (55-85%) and fine (more than 85%) grinding.

The efficiency of beneficiation plants largely depends on the quality of the processed raw materials. To obtain maximum extraction of useful components during beneficiation of ore raw materials, its composition must be constant over time, at least during a shift. In conditions of frequent changes in the chemical and mineralogical composition of the processed raw materials or delays in information about them, beneficiators are not able to promptly change the ore processing mode. This problem can be eliminated by introducing flow analyzers, such as ARP-1C, operating in online mode into the industrial beneficiation process. Such analyzers allow monitoring changes in the concentrations of elements in the ore on the flow in real time, which allows beneficiators to apply quick and timely decisions on changes in the beneficiation process, without any time delays. In addition, devices such as ARP-1C allow continuous monitoring of other elements that are not interesting from the point of view of extraction, affecting the conditions of the flotation process. For example, flotation extraction of oxidized lead minerals from heavily degraded ores becomes virtually impossible if they contain manganese oxides and hydroxides.

In general, the stages of the beneficiation process of non-ferrous metal ores include the following stages:

• Crushing and grinding of ore.
• Screening and classification (separation into size classes).
• Basic enrichment processes.
• Final operations.

The main enrichment processes include all kinds of processes such as:

• Flotation methods based on the difference in wettability of ore components with water.
• Methods of electrical separation based on differences in the electrical conductivity of components, or in the ability to acquire different charges under the influence of certain factors.
• Methods based on the use of differences in grain shape and friction coefficients of ore components.

Thus, the decisive factor in determining the necessary ore enrichment process, as well as the conditions for carrying out this process, is reliable and timely information about the component composition of the ore, which is the task of the ARP-1C type flow analyzers of the substance.