Dressing for most ordinary people may be unfamiliar with, why say this, the reason is because I often encounter such a thing. Because I am a worker of Xinhai mining machinery company, so sometimes some of the around friends and family will often ask questions about the mines, but I think most of these problems are some very simple and basic problems. So I arranged some frequently encountered questions roughly in my spare time. I believe through these 7 questions even the people who know nothing about beneficiation industry can have a general understand about this industry.
Question one: What is called beneficiation?
According to the physical properties of minerals or the difference in physical and chemical properties of minerals and by means of varies mining equipment to separate the gangue minerals with other valuable minerals, the process of enriching the valuable minerals is called beneficiation.Question two: Why dressing?The ore exploited from underground generally contain valuable minerals and gangue minerals. The grade is very low, so we need to remove most of the gangue minerals and the harmful ingredients to enrich the valuable minerals for the later processing.
Question three: What are the common minerals?
Minerals are native elements or natural compounds fixed with chemical compositions and physical and chemical properties, which are products of the natural physical and chemical effects and the biochemical effects. They are parts of rock or ore. Except for a few nature minerals are natural elements such as gold (Au), natural silver (Ag), natural copper (Cu), natural sulphur (S), graphite(C), diamond (C), most of minerals are natural compounds, for example, magnetic iron (Fe3O4), silica (SiO2), galena (PbS), chalcopyrite (CuFeS2) and so on.
Question four: What are the general steps of beneficiation process?
Ore from the stope need to go through each beneficiation operate process, at last to get in line with the requirements of the smelting concentrate, as shown below.
It mainly includes three steps: Firstly, preparing activities. It specifically includes crushing, screening, grinding and classification. Secondly, separating activities. It specifically includes gravity separation, flotation, electricity, etc. Thirdly, dehydrating activities. It specifically includes concentration, filtration, drying and so on.Question five: what is the meaning of ore grade?
The ore grade refers to the amount of some metals or some valuable components in the ore, and it generally represented with percentage. Alpha is usually used to represent ore grade; Beta represents concentrate grade; Theta represents tailings grade. If there are problems in mineral processing production, we generally make analysis among these three grades.
Question six: What does concentrate, tailing, or middling respectively mean?
Concentrate is the product of removing most of gangue and impurities in the ore and the enrichment of the valuable minerals. Concentrate is the ultimate product of concentrator.Tailing is the last product with few valuable components. Its the last remaining useless materials after steps of refining and screening the raw ore.
Middling is an intermediate product obtained during separating. Its valuable components are between the concentrate and the tailing, so we need to re-concentrate it or treat it separately.
Question seven: What methods are commonly used in beneficiation?There are four method commonly used in beneficiation: gravity separation, flotation, magnetic separation and electric separation.
Gravity separation method is based on the differences of mineral relative density (weight) to mineral separation. The principle of which is according to the loose stratification and separation conditions formed by the hydrodynamic and the various mechanical force of different densities of the mineral particles affect in the moving medium (water, air and heavy liquid)
Flotation method is according to the differences of physical and chemical properties of the mineral surface, and as a result of adopting flotation reagent, the valuable minerals are attached to the bubbles selectively in which to separate minerals. Flotation method is generally used to separate nonferrous metals such as cooper, lead, zinc.
Magnetic separation method is according to different magnetic of minerals, and they can get different forces in the magnetic field of magnetic separator, in this way to separate minerals. Its mainly used to separate the ferrous metals such as iron, manganese, chromium.
Electric separation method is according to the different conductivity of the minerals to separate minerals. Because of the different conductivity of the minerals, the electrostatic forces acting on the mineral is also different when mineral through the high voltage electric field of electromagnetic separator in which to separate minerals. Its mainly used to separate the mixed coarse-fine ore and fine ore Such as the electric separation of white tungsten and cassiterite, and the separate of zircon.