When looking at commercially valuable minerals, the question rightly arises as to how such an attractive piece of jewelry can be made from primary ore or fossil. Especially considering the fact that rock processing as such represents, if not one of the final, then at least a process of refining that precedes the final stage. The answer to the question will be enrichment, during which basic processing of the rock occurs, involving the separation of valuable minerals from empty media.
General enrichment technology
Processing of valuable minerals is carried out at special enrichment plants. The process involves performing several operations, including preparation, direct splitting and separation of rock with impurities. During enrichment, various minerals are obtained, including graphite, asbestos, tungsten, ore materials, etc. These do not necessarily have to be valuable rocks - there are many factories that process raw materials, which are later used in construction. One way or another, the basics of mineral processing are based on an analysis of the properties of minerals, which also determine the principles of separation. By the way, the need to cut off different structures arises not only for the purpose of obtaining one pure mineral. It is a common practice for several valuable breeds to be bred from one structure.
Rock crushing
At this stage, the material is crushed into individual particles. During the crushing process, mechanical forces are used to overcome the internal adhesion mechanisms.
As a result, the rock is divided into small solid particles that have a homogeneous structure. It is worth distinguishing between direct crushing and grinding techniques. In the first case, the mineral raw material undergoes a less deep separation of the structure, during which particles with a fraction of more than 5 mm are formed. In turn, grinding ensures the formation of elements with a diameter of less than 5 mm, although this indicator depends on what kind of rock you are dealing with. In both cases, the task is to maximize the splitting of the grains of the useful substance so that a pure component is released without a mix, that is, waste rock, impurities, etc.
Screening process
After completion of the crushing process, the harvested raw materials are subjected to another technological impact, which can be either sieving or weathering. Screening is essentially a method of classifying the resulting grains according to their size characteristics. The traditional way of implementing this stage involves the use of a sieve and a sieve, provided with the ability to calibrate the cells. During the screening process, over-grid and under-grid particles are separated. In some way, the enrichment of minerals begins at this stage, since some of the impurities and mixes are separated. Small fractions less than 1 mm in size are also sifted out using air - by weathering. The mass, reminiscent of fine sand, is lifted by artificial air currents and then settles.
Subsequently, particles that settle more slowly are separated from very small dust elements that linger in the air. For further collection of the derivatives of such screening, water is used.
Enrichment processes
The enrichment process aims to separate mineral particles from the feedstock. During such procedures, several groups of elements are isolated - useful concentrate, waste tailings and other products. The principle of separating these particles is based on the differences between the properties of useful minerals and waste rock. Such properties can be the following: density, wettability, magnetic susceptibility, size, electrical conductivity, shape, etc. Thus, enrichment processes that use differences in density use gravitational separation methods. This approach is used for ore and non-metallic raw materials. Enrichment based on the wettability characteristics of the components is also very common. In this case, the flotation method is used, a feature of which is the ability to separate fine grains.
Magnetic enrichment of minerals is also used, which makes it possible to separate ferrous impurities from talc and graphite media, as well as to purify tungsten, titanium, iron and other ores. This technique is based on the difference in the effect of a magnetic field on fossil particles. The equipment used is special separators, which are also used for the recovery of magnetite suspensions.
Final stages of enrichment
The main processes of this stage include dehydration, pulp thickening and drying of the resulting particles. The selection of equipment for dehydration is based on the chemical and physical characteristics of the mineral. As a rule, this procedure is performed in several sessions. However, the need for its implementation does not always arise. For example, if electrical separation was used in the enrichment process, then dewatering is not required. In addition to preparing the enrichment product for further processing processes, appropriate infrastructure must be provided for handling mineral particles. In particular, the factory organizes appropriate production services. Intra-shop vehicles are introduced, and the supply of water, heat and electricity is organized.
Beneficiation equipment
At the grinding and crushing stages, special installations are used. These are mechanical units that, with the help of various driving forces, have a destructive effect on the rock. Next, in the screening process, a sieve and sieve are used, in which the possibility of calibrating the holes is provided. More complex machines called screens are also used for sifting. Direct enrichment is carried out by electric, gravitational and magnetic separators, which are used in accordance with the specific principle of structure separation. After this, drainage technologies are used for dewatering, in the implementation of which the same screens, elevators, centrifuges and filtration devices can be used. The final stage, as a rule, involves the use of heat treatment and drying agents.
Waste from the enrichment process
As a result of the enrichment process, several categories of products are formed, which can be divided into two types - useful concentrate and waste. Moreover, a valuable substance does not necessarily have to represent the same rock. It also cannot be said that waste is unnecessary material. Such products may contain valuable concentrate, but in minimal quantities. At the same time, further enrichment of minerals that are in the waste structure is often not technologically and financially justified, so secondary processes of such processing are rarely carried out.
Optimal enrichment
Depending on the enrichment conditions, the characteristics of the starting material and the method itself, the quality of the final product may vary. The higher the content of valuable components and the fewer impurities in it, the better. Ideal ore beneficiation, for example, involves the complete absence of waste in the product. This means that in the process of enriching the mixture obtained by crushing and screening, debris particles from waste rock were completely excluded from the total mass. However, it is not always possible to achieve such an effect.
Partial beneficiation of minerals
Partial enrichment refers to the separation of the size class of the fossil or the cutting off of an easily separated part of the impurities from the product. That is, this procedure does not aim to completely clean the product from impurities and waste, but only increases the value of the source material by increasing the concentration of useful particles. Such processing of mineral raw materials can be used, for example, to reduce the ash content of coal. During the enrichment process, a large class of elements is isolated upon further mixing of the concentrate of unenriched screenings with the fine fraction.
The problem of loss of valuable rock during enrichment
Just as unnecessary impurities remain in the mass of the useful concentrate, the valuable rock can be removed along with the waste. To account for such losses, special tools are used to calculate the permissible level for each of the technological processes. That is, individual standards for acceptable losses are developed for all separation methods. The acceptable percentage is taken into account in the balance of processed products in order to cover discrepancies in the calculation of the moisture coefficient and mechanical losses. Such accounting is especially important if ore beneficiation is planned, during which deep crushing is used. Accordingly, the risk of losing valuable concentrate increases. And yet, in most cases, the loss of useful rock occurs due to violations in the technological process.
Conclusion
Recently, technologies for the enrichment of valuable rocks have made a noticeable step in their development. Both individual processing processes and general separation schemes are being improved. One of the promising directions for further advancement is the use of combined processing schemes that improve the quality characteristics of concentrates. In particular, magnetic separators are combined, resulting in an optimized enrichment process. New techniques of this type include magnetohydrodynamic and magnetohydrostatic separation. At the same time, there is also a general tendency for the deterioration of ore rocks, which cannot but affect the quality of the resulting product. An increase in the level of impurities can be combated by the active use of partial enrichment, but in general, an increase in processing sessions makes the technology ineffective.
7. What is meant by the terms chemical and radiometric enrichment?
8. What is called enrichment by friction, decripitation?
9. What are the formulas for technological indicators of enrichment?
10. What is the formula for the degree of reduction?
11. How to calculate the degree of ore enrichment?
Seminar topics:
Main characteristics of enrichment methods.
Main differences from preparatory, auxiliary and main enrichment methods.
Brief description of the main enrichment methods.
Brief description of preparatory and auxiliary enrichment methods.
The degree of sample reduction is the main role of this method in mineral processing.
Homework:
Study the terms, rules and basic methods of enrichment, consolidate the acquired knowledge in a seminar lesson on your own.
LECTURE No. 3.
TYPES AND SCHEMES OF ENRICHMENT AND THEIR APPLICATION.
Purpose: To explain to students the main types and schemes of enrichment and the application of such schemes in production. Give an idea of the methods and processes of mineral processing.
Plan:
Methods and processes of mineral processing, their scope.
Concentrating factories and their industrial significance. Basic types of technological schemes.
Key words: main processes, auxiliary processes, preparatory methods, application of processes, diagram, technological scheme, quantitative, qualitative, qualitative-quantitative, water-sludge, apparatus circuit diagram.
1. At processing factories, minerals are subjected to successive processing processes, which, according to their purpose in the technological cycle of the factory, are divided into preparatory, processing and auxiliary.
For preparatory operations usually include crushing, grinding, screening and classification, i.e. processes that result in the disclosure of the mineral composition, suitable for their subsequent separation during the beneficiation process, as well as averaging operations of minerals, which can be carried out in mines, quarries, mines and processing plants. When crushing and grinding, a reduction in the size of pieces of ore and the opening of minerals is achieved as a result of the destruction of intergrowths of useful minerals with waste rock (or intergrowths of some valuable minerals with others). Screening and classification are used to separate mechanical mixtures obtained by crushing and grinding by size. The task of the preparatory processes is to bring mineral raw materials to the size necessary for subsequent enrichment.
To the main beneficiation operations include those physical and physico-chemical processes of separation of minerals, in which useful minerals are separated into concentrates, and waste rock into tailings. The main beneficiation processes include processes of separation of minerals according to physical and physico-chemical properties (shape, density, magnetic susceptibility, electrical conductivity, wettability, radioactivity, etc.): sorting, gravity, magnetic and electrical enrichment, flotation, radiometric enrichment, etc. As a result of the main processes, concentrates and tailings are obtained. The use of one or another beneficiation method depends on the mineralogical composition of the ore.
To auxiliary processes include procedures for removing moisture from enrichment products. Such processes are called dehydration, which is carried out to bring the moisture content of products to established standards.
At the processing plant, the feedstock during processing is subjected to a number of sequential technological operations. A graphical representation of the totality and sequence of these operations is also called technological scheme of enrichment.
When beneficiating minerals, differences in their physical and physicochemical properties are used, of which significant importance is color, shine, hardness, density, cleavage, fracture, etc.
Color minerals are varied . The difference in color is used in manual mining or sampling of coals and other types of processing.
Shine minerals is determined by the nature of their surfaces. The difference in gloss can be used, as in the previous case, for manual picking of ore from coals or sampling from coals and other types of processing.
Hardness minerals that make up minerals is important when choosing methods for crushing and beneficiation of certain ores, as well as coals.
Density minerals varies widely. The difference in density between useful minerals and waste rock is widely used in mineral processing.
Cleavage minerals lies in their ability to split from impacts in a strictly defined direction and form smooth surfaces along the split planes.
Kink has significant practical importance in beneficiation processes, since the nature of the surface of the mineral obtained by crushing and grinding has an impact during beneficiation by electrical and other methods.
2. Mineral processing technology consists of a series of sequential operations carried out at processing plants.
Processing plants are industrial enterprises in which mineral resources are processed using beneficiation methods and one or more commercial products with a high content of valuable components and a reduced content of harmful impurities are isolated from them. A modern processing plant is a highly mechanized enterprise with a complex technological scheme for processing minerals.
The set and sequence of operations to which ore is subjected during processing constitute enrichment schemes, which are usually depicted graphically
Technology system includes information about the sequence of technological operations for processing minerals at a processing plant.
Qualitative scheme contains information on the qualitative measurements of the mineral during its processing, as well as data on the mode of individual technological operations. Qualitative scheme(Fig. 1.) gives an idea of the adopted ore processing technology, the sequence of processes and operations to which ore is subjected during enrichment.
rice. 1. High-quality enrichment scheme
Quantitative scheme includes quantitative data on the distribution of minerals among individual technological operations and the yield of the resulting products.
Qualitative-quantitative scheme combines data from qualitative and quantitative enrichment schemes.
If the scheme contains data on the amount of water in individual operations and enrichment products, and on the amount of water added to the process, then the scheme is called slurry. The distribution of solids and water across operations and products is reported as a solid to liquid ratio S:L, such as S:L = 1:3, or as a percentage solid, such as 70% solid. The T:W ratio is numerically equal to the amount of water (m³) per 1 ton of solids. The amount of water added to individual operations is expressed in cubic meters per day or cubic meters per hour. Often these types of schemes are combined and then the scheme is called qualitative-quantitative slurry.
Introductory-sludge scheme contains data on the ratio of water and solids in enrichment products.
Device circuit diagram– a graphic representation of the path of movement of minerals and enrichment products through the apparatus. In such diagrams, devices, machines and vehicles are depicted conventionally and their number, type and size are indicated. The movement of products from unit to unit is indicated by arrows (see Fig. 2):
Rice. 2. Device circuit diagram:
1.9- bunker; 2, 5, 8, 10, 11 - conveyor; 3, 6 - screens;
4 - jaw crusher; 7 - cone crusher; 12 - classifier;
13 - mill; 14 - flotation machine; 15 - thickener; 16 - filter
The diagram in the figure shows in detail how the ore undergoes complete enrichment, including the preparatory and main enrichment processes.
Flotation, gravitational and magnetic enrichment methods are most often used as independent processes. Of two possible methods that give the same enrichment rates, the most economical and environmentally friendly method is usually chosen.
Conclusions:
Enrichment processes are divided into preparatory and main auxiliary.
When beneficiating minerals, differences in their physical and physicochemical properties are used, of which color, shine, hardness, density, cleavage, fracture, etc. are essential.
The set and sequence of operations to which ore is subjected during processing constitute enrichment schemes, which are usually depicted graphically. Depending on the purpose, the schemes can be qualitative, quantitative, or slurry. In addition to the indicated diagrams, circuit diagrams of devices are usually drawn up.
A qualitative beneficiation scheme depicts the path of movement of ore and beneficiation products sequentially through operations, indicating some data on qualitative changes in ore and beneficiation products, for example, size. A qualitative scheme gives an idea of the stages of the process, the number of cleaning operations of concentrates and control cleaning of tailings, the type of process, the method of processing middlings and the number of final enrichment products.
If a qualitative diagram indicates the amount of ore processed, the products obtained in individual operations and the content of valuable components in them, then the scheme will already be called quantitative or qualitative-quantitative.
The set of diagrams gives us a complete understanding of the ongoing process of enrichment and processing of minerals.
Control questions:
1. What refers to the preparatory, main and auxiliary processes of enrichment?
2. What differences in mineral properties are used in mineral processing?
3. What are concentrating factories called? What are their uses?
4. What types of process flow diagrams do you know?
5. What is a circuit diagram of devices.
6. What does a quality process flow diagram mean?
7. How can you characterize the qualitative-quantitative enrichment scheme?
8. What does the water-slurry scheme mean?
9. What characteristics can be obtained by following technological schemes?
Preparatory processes for mineral processing
Introduction
Purpose of mineral processing
The mined rock mass is a mixture of pieces of mineral complexes, mineral aggregates with different physical, physicochemical and chemical properties. To obtain final products (metal concentrates, coke, building materials, chemical fertilizers, etc.), it must be subjected to a number of processing processes: mechanical, thermal, chemical.
Processing of minerals at a processing plant includes a number of operations, as a result of which separation of useful components from impurities is achieved, those. bringing the mineral to a quality suitable for subsequent processing, for example, it is necessary to increase the content: iron from 30-50% to 60-70%; manganese from 15-25% to 35-45%, copper from 0.5-1.5% to 45-60%, tungsten from 0.02-0.1% to 60-65%.
According to their purpose, mineral processing processes are divided into preparatory, basic(enrichment) and auxiliary.
Preparatory processes are designed to open or open the grains of useful components (minerals) that make up minerals, and dividing them into size classes, satisfying the technological requirements of subsequent enrichment processes.
The preparatory processes include crushing, grinding, screening and classification.
Mineral beneficiation is a set of processes of mechanical processing of mineral raw materials, which makes it possible to separate useful minerals (concentrate) from waste rock.
Specialist enrichment engineers must solve the following tasks:
Integrated development of mineral resources;
Disposal of processed products;
Creation of new processes of waste-free technology for separating minerals into final marketable products for their use in industry;
Environmental protection.
Mineral mixtures are separated based on differences in physical, physico-chemical and chemical properties to obtain a number of products with a high content of valuable components (concentrates) , low (industrial products) and insignificant (waste, tailings) .
The enrichment process is aimed not only at increasing the content of the valuable component in the concentrate, but also at removing harmful impurities:
sulfur in the coal phosphorus in manganese concentrate, arsenic in brown iron ore and sulfide polymetallic ores. These impurities, getting into cast iron and then into steel, worsen the mechanical properties. metal properties.
Brief information about minerals
Minerals are ores, non-metallic and combustible fossil materials used in industrial production in natural or processed form.
TO ores refer to minerals that contain valuable components in quantities sufficient to make their extraction economically profitable.
Ores are divided into metal and non-metal.
Metal ores- raw materials for the production of ferrous, non-ferrous, rare, precious and other metals - tungsten-molybdenum, lead-zinc, manganese, iron, cobalt, nickel, chromite, gold-containing;
non-metallic ores- asbestos, barite, apatite, phosphorite, graphite, talc, antimony, etc.
Non-metallic minerals - raw materials for the production of building materials (sand, clay, gravel, building stone, Portland cement, building gypsum, limestone, etc.)
Combustible minerals - solid fuel, oil and flammable gas.
Minerals consist of minerals that differ in their value, physical and chemical properties (hardness, density, magnetic permeability, wettability, electrical conductivity, radioactivity, etc.).
Minerals- called native (i.e. found in nature in its pure form) elements and natural chemical compounds.
Useful mineral (or component)- called an element or its natural compound, for the purpose of obtaining which the extraction and processing of a mineral is carried out. For example: in iron ore, useful minerals are magnetite Fe 3 O 4, hematite Fe 2 O 3.
Useful impurities- are called minerals (elements), the content of which in small quantities leads to an improvement in the quality of products obtained from useful minerals. For example, impurities vanadium, tungsten, manganese, chromium in iron ore have a positive effect on the quality of the metal smelted from it.
Harmful impurities- are called minerals (elements), the content of which in small quantities leads to a deterioration in the quality of products obtained from useful minerals. For example, impurities sulfur, phosphorus, arsenic negatively affect the steelmaking process.
Satellite elements are components contained in a mineral in small quantities, released during the enrichment process into separate products or the product of the main component. Further metallurgical or chemical processing of satellite elements allows them to be extracted into a separate product.
Gang minerals- are called components that have no industrial value. In iron ore, these may include SiO 2, Al 2 O 3.
Depending on the structure, minerals are distinguished interspersed and solid, for example, in disseminated - individual small grains of a useful mineral are scattered among the grains of waste rock; in solid - grains of useful mineral are presented mainly as a solid mass, and waste rock minerals are in the form of interlayers and inclusions.
(lecture notes)
V.B.Kuskov
SAINT PETERSBURG
INTRODUCTION 2
1. preparatory processes 8
1.1.
GRANULOMETRIC COMPOSITION 8
1.2 CRUSHING 10
1.3.
screening 14
1.4.
GRINDING 17
1.5.
HYDRAULIC CLASSIFICATION 20
2. MAIN ENRICHMENT PROCESSES 23
2.1.
GRAVITY METHOD OF ENRICHMENT 23
2.3.
MAGNETIC METHOD OF ENRICHMENT 35
2.4.
ELECTRICAL ENRICHMENT 39
2.5.
special ENRICHMENT METHODS 43
2.6. COMBINED ENRICHMENT METHODS 48 3 AUXILIARY PROCESSES 49 3.1.
Solid minerals (ores), in turn, are divided into combustible (peat, shale, coal) and non-combustible, which are: agronomic (apatite and phosphorite, etc.), non-metallic (quartz, barite, etc.) and metal (ores ferrous and non-ferrous metals). The efficiency of using a particular mineral depends, first of all, on the content of a valuable component and the presence of harmful impurities. Direct metallurgical or chemical processing of a mineral is advisable (technically and economically profitable) only if the content of a useful component in it is not lower than a certain limit determined by the level of development of technology and technology (and the need for this raw material) at the present time. In most cases, the direct use of the mined rock mass or its processing (metallurgical, chemical, etc.) is not economically feasible, and sometimes technically impossible, because minerals suitable for direct processing are rare in nature; in most cases they are subjected to special processing - enrichment.
Mineral beneficiation a set of processes of mechanical processing of mineral raw materials in order to extract useful (valuable) components and remove waste rock and harmful impurities. As a result of beneficiation, concentrate(s) and tailings are obtained from ore.
Concentrate- this is the product where most of the useful minerals (and a small amount of waste rock minerals) are released (concentrated). The quality of the concentrate is mainly characterized by the content of a valuable component ( it is always higher than in ore, the concentrate is richer in valuable components, hence the name - enrichment), as well as in the content of useful and harmful impurities, humidity and granulometric characteristics.
Tails- a product into which most of the waste rock minerals, harmful impurities and a small amount of useful components will be released (the content of valuable components in tailings is lower than in concentrates and ore).
In addition to concentrate and tailings, it is possible to obtain industrial products, i.e. products characterized by a lower content of useful components compared to concentrates and a higher content of useful components compared to tailings.
Useful(valuable) components are chemical elements or natural compounds for the production of which a given mineral is mined and processed. As a rule, the valuable component in the ore is in the form of a mineral (there are few native elements in nature: copper, gold, silver, platinum, sulfur, graphite).
Useful impurities are chemical elements or natural compounds that are part of a mineral in small quantities and improve the quality of the finished product (or are released during further processing). For example, useful impurities in iron ores are alloying additives such as chromium, tungsten, vanadium, manganese, etc.
Harmful impurities refers to individual elements and natural chemical compounds contained in minerals in small quantities and having a negative impact on the quality of the finished product. For example, harmful impurities in iron ores are sulfur, arsenic, phosphorus, in coking coals - sulfur, phosphorus, in thermal coals - sulfur, etc.
Mineral beneficiation makes it possible to increase economic efficiency of their further processing, also, in some cases, without an enrichment stage, further processing becomes completely impossible. For example, copper ores (which typically contain very little copper) cannot be directly smelted into metallic copper, since the copper turns into slag when smelted. In addition, mineral processing allows:
increase industrial reserves of raw materials through the use of deposits of poor mineral resources with a low content of valuable components;
increase labor productivity at mining enterprises and reduce the cost of mined ore through mechanization of mining operations and continuous mining of minerals instead of selective ones;
comprehensive use of minerals, since preliminary enrichment makes it possible to extract not only the main useful components, but also accompanying ones contained in small quantities;
reduce the cost of transporting richer products to consumers, rather than the entire volume of extracted minerals;
to isolate from mineral raw materials those harmful impurities that, during further processing, can pollute the environment and thereby threaten human health and deteriorate the quality of the final product.
Enrichment methods can also be used in the processing of solid household waste (350–400 kg/year per person is generated).
Minerals at processing plants undergo a number of sequential operations, as a result of which useful components are separated from impurities. Mineral enrichment processes according to their purpose are divided into preparatory, auxiliary and main.
TO preparatory include crushing, grinding, screening and classification processes. Their task is to separate the useful mineral and waste rock (“open” the joints) and create the desired granulometric characteristics of the processed raw materials.
Task main enrichment processes - to separate useful mineral and waste rock. To separate minerals, differences in the physical properties of the minerals being separated are used. These include:
|
Name of enrichment method |
Physical properties used for separation |
Main types of minerals enriched by this method |
|
Gravity enrichment method |
Density (taking into account size and shape) |
Coals (+1 mm), shales, gold-bearing, tin ores... |
|
Flotation enrichment method |
Surface wettability |
Non-ferrous metal ores, apatite, phosphorite, fluorite ores... |
|
Magnetic enrichment method |
Specific magnetic susceptibility |
Iron ores... |
|
Electric enrichment method |
Electrical properties (electrical conductivity, tribocharge, dielectric constant, pyrocharge) |
Finishing of diamond ores, rare metals: titanium-zirconium, tantalum-niobium, tin-tungsten, rare earth (monazite-xenotime). Glass sands, electronic scrap... |
|
Ore sorting: Ore dismantling Radiometric enrichment |
External signs: color, shine, shape The ability of particles to emit, reflect and absorb various types of energy |
Gemstones, mica sheets, long-fiber asbestos Ores of ferrous and non-ferrous metals, diamond-containing, fluorite and other ores |
|
Selective crushing |
Difference in strength |
Phosphorite ores, coals and shale |
|
Enrichment by form | ||
|
Combined methods |
In addition to traditional enrichment processes (which do not affect the chemical composition of the raw material), the scheme includes pyro- or hydrometallurgical operations that change the chemical composition of the raw material. |
Uranium, gold-bearing (root) ores, copper-nickel ores... |
In addition to those listed, there are other enrichment methods. Also, sometimes agglomeration processes (increasing the size of materials) are classified as enrichment processes.
TO auxiliary include dewatering, dust collection, wastewater treatment, sampling, control and automation. The task of these processes is to ensure the optimal flow of the main processes and to bring the separation products to the required conditions.
The set of sequential technological processing operations to which minerals are subjected at processing plants is called enrichment scheme. Depending on the nature of the information contained in the enrichment scheme, it is called technological, qualitative, quantitative, qualitative-quantitative, water-sludge and apparatus chain diagram.
Enrichment, like any other technological process, is characterized by indicators. The main technological indicators of enrichment are as follows:
Q product mass (productivity); P – mass (performance) of the design component in the product . They are usually expressed in tons per hour, tons per day, etc.;
content of the calculated component in the product – , is the ratio of the mass of the calculated component in the product to the mass of the product; The content of various components in a mineral and in the resulting products is usually calculated as a percentage (sometimes the content in the source material is denoted , in the concentrate - , in tailings - ). The content of useful components in the extracted raw materials (ore) can range from fractions of a percent (copper, nickel, cobalt, etc.) to several percent (lead, zinc, etc.) and several tens of percent (iron, manganese, fossil coal and some other non-metallic minerals);
product yield – and, to, xv is the ratio of the mass of the product to the mass of the original ore; the yield of any enrichment product is expressed as a percentage, less often in fractions of a unit;
extraction of a valuable component – i, k, xv is the ratio of the mass of the calculated component in the product to the mass of the same component in the original ore; recovery is expressed as a percentage, less often as a fraction of a unit.
Exit i– th product is calculated by the formula:
i = (Q i /Q ref)100,%
Also, in the case of separation into two products - concentrate and tailings, their yield can be determined through the content using the following formulas:
k = 100,%; xv = 
100,%;
The sum of the concentrate and tailings yields is:
k + xv = 100%.
It's obvious that
Q con + Q xv = Q ref.;
R con + R xv = R ref.
1 + 2 +…+ n = 100%.
Likewise for Q and R.
(When beneficiating minerals, as a rule, only two products are obtained - concentrate and tailings, but not always, sometimes there may be more products).
.
In practice, contents are usually determined by chemical analysis.
Extracting the useful component into i– product:
i
=
100.%, or i = 
%.
The sum of concentrate and tailings recoveries is:
k + xv = 100%.
This formula is valid for any number of products:
1 + 2 +… n = 100%.
To find the content of a mixed product, you can use the so-called balance equation (for the case of separation into two products):
to con + xv con = out out.
The equation is also valid for any number of products:
1 1 + 2 2 +…+ n n = out out.
It should be noted that out = 100%.
Example. The ore is divided into two products (Fig. 1.1) – concentrate and tailings. Ore productivity Q out = 200 t/h, for concentrate – Q con = 50 t/h. Performance by calculation component R out = 45 t/h, for component in concentrate R con = 40 t/h.
Q xv = Q ref – Q con = 200 – 50 = 150 t/h;
con = ( Q con/ Q ref)100 = (50/200)100 = 25%;
xv = out – k = 100 – 25 = 75%,
or xv = ( Q xv/ Q out)100 =(150/200) . 100=75%;
it's obvious that Q xv = ( xv Q out)/100 = (75200)/100 = 150 t/h;
=
=
=
22,5 %;
=
=
=
80 %;
R xv = R ref – R con = 45 – 40 = 5,
Then 
=
=
=3,33 %.
Or, using the balance equation, we have:
to con + xv con = out out,
xv = 
=
=
3,33 %.
The processes of processing minerals according to their intended purpose in the technological cycle of the factory are divided into preparatory, actually enrichment and auxiliary.
TO preparatory operations include crushing, grinding, screening and classification, as well as mineral averaging operations, which can be carried out in mines, quarries, mines and processing plants.
TO main enrichment processes include those physical and physicochemical processes of mineral separation, in which useful minerals are released into concentrates, and waste rock into waste.
TO auxiliary processes include processes for removing moisture from enrichment products. Such processes are called dehydration, which is carried out to bring the moisture content of products to established standards. Auxiliary processes include the treatment of industrial wastewater (for reuse or discharge into water bodies) and dust collection processes.
When beneficiating minerals, differences in their physical and physicochemical properties are used, of which color, shine, hardness, density, cleavage, fracture, magnetic, electrical and some other properties are essential.
Color minerals are varied. The difference in color is used during manual ore sorting or rock sampling from coals and other types of processing.
Shine minerals is determined by the nature of their surfaces. The difference in gloss can be used, as in the previous case, during manual ore sorting or rock sampling from coals or during other types of processing.
Hardness minerals that make up minerals is important when choosing methods for crushing and beneficiation of certain ores, as well as coals. Minerals with lower hardness are crushed and ground faster than minerals with higher hardness. By applying selective crushing or grinding, subsequent separation of such minerals can be carried out on a screen.
Density minerals varies widely. The difference in density between useful minerals and waste rock is widely used in the beneficiation of ores and coals.
Cleavage minerals lies in their ability to split from impacts in strictly defined directions and form smooth surfaces along the split planes. Cleavage is important for the choice of crushing and grinding methods, as well as the removal of crushed materials from beneficiation products by screening and classification.
Kink has significant practical importance in beneficiation processes, since the nature of the surface of the mineral obtained by crushing and grinding has an impact during beneficiation by electrical and other methods.
Magnetic properties minerals are used in the enrichment of minerals with different magnetic susceptibility in magnetic fields of different strengths.
Electrical The properties of minerals are used in electrical beneficiation methods associated with a different ratio of mineral particles to the action of electrical and mechanical forces when moving in an electric field.
Physicochemical characteristics the surfaces of mineral particles are used in flotation processes, which involve their different relationship to the aquatic environment and the effect of chemicals (reagents) on them.
At the processing plant, the feedstock during processing is subjected to a number of sequential technological operations. A graphical representation of the totality and sequence of these operations is called technological scheme of enrichment.
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