Mining equipment and processing it using a lot of crushers and other mining equipment. The mining process also has an environmental impact on its surroundings

Content

1. A Brief History of Mining and Mining Machines.
2. Reduce the environmental impact of mining.

The machine extracts minerals and geological materials from the earth

In general, mining refers to the extraction of minerals and geological materials from the earth, the rock or the seal. Nowadays, mining retains various elements because these materials are not cultivated, converted into agriculture or artificially created. Precious metals, coal, diamonds and gold are excellent examples. Non-renewable sources such as natural gas, oil and even water are also being promoted. The use of suitable mining equipment realizes the difficult and difficult task of mining.

Prehistoric mines

The primitive civilization has used the country's resources through mining for various purposes. Most minerals and early mines were used for the production of weapons and other tools. At this time, high-quality flint, which consists of sedimentary rocks, has already been sought in parts of Europe. They were used as weapons in the Stone Age. Despite limited mining equipment, Neanderthals were able to extract and manufacture improvised tools.





Because of their wealth and power, the ancient Egyptian civilization was one of the first to succeed in mining minerals. They used malachite and gold. Green stones were mainly used for ceramics and ornaments. Later, the Egyptians began mining minerals that were not found in their land. Using iron tools as mining equipment, they searched for minerals, mainly Nubian gold. Fire suppression has been a popular method of extracting gold from minerals. The rock containing the mineral is placed against a rock surface for heating and then sprayed with water. The installation of fire was perhaps the most popular method at the time.

It is the Romans who have made great progress in the history of mining. They were the first to use large-scale extraction methods. As water volume for the operation of simple machines, for the removal of deposits, etc. This is referred to as hydraulic or hydraulic mining. It is a form of mining in which stones and other debris are moved with high pressure water shocks.

In the 1300s, the demand for metal for swords, armor and other weapons increased dramatically. Other minerals such as iron and silver were largely recovered. The demand for coins has risen so much that money shortages have emerged. During this time, iron became an indispensable element of building construction. Machines and other mining machines have become common.

From mining mines, water mills and black dust have become bulldozers, explosives, trucks, etc. Other technological innovations, such as the use of green light lasers in the mines for sawing and machine alignment, help miners in quarries.

The prehistoric tools now use the large machines to offload the land efficiently and quickly. They are also used to break and remove rocks, even mountains. Custom engineering teams are now involved in the mining of various valuable minerals and other bedding materials such as plaster and salt.

Today, there are five categories of mining: coal, metal ore, non-metallic mining, oil and gas production. Oil and gas production remains one of the largest industries in the world.

Pollution from mining has always been controversial

Many years ago, those familiar with the degradation process know that this practice has caused great damage to the environment in the past. One of the main causes of this situation is the fact that fossil fuels are not renewable. As a result, many mining companies have experienced controversy over pollution in local communities.

Fortunately, things have developed positively in recent years as more and more mining companies have a genuine interest in promoting green practices in their operations. This, of course, in coordination with government agencies and other interested organizations.

For example, large mining companies took the initiative to plant trees in quarries, on old mines, on undeveloped land, on the roadside and even near their offices. Some of them even set goals (eg planting 2,000 trees a year) to measure their progress while having a significant impact.

In addition, some companies around the world have discovered that the waste they recover during production can be used to build houses. Although coal mines often contaminate the water, the cleaning process produces gypsum, a material that can be used to make high quality bricks that are ideal for housing.

Another improvement in all mining operations is the effort to ensure that the extraction of diamonds and other precious stones is always ethical. In addition, recycled metals are used in jewellery making.

In addition, mining companies have partnered with energy management companies to help less-developed countries develop effective mining plans with less environmental impact. Appropriate practices will be taught and the use of modern tools and machinery will be encouraged. Of course, miners use safety equipment and equipment to avoid potential risks.

While advances in mining technology have mainly promoted large-scale operations, experts have repeatedly pointed out that small-scale mining is not as dangerous to the environment, making it a viable option for those wishing to explore the area , To achieve the desired results, conventional extraction methods (such as washing gold fragments with gravel water) can be used. Deep excavation and the use of chemicals are not required for this type of process.

Building sand is a loose material with a grain size of up to 5 mm. To improve the quality it is sometimes enriched with gravel up to 3 mm. It must be sure that they belong to the 1st class of radioactivity. It is not allowed to react with water and bases.

Content

     1. How do you use the arena of the race?.
     2. Varieties and their technical characteristics..
     3. How do I get alluvial sand?.
     4. Application of washed sand.
     5. Properties of per-coated sand.
     6. Which sand is the best alluvial or purebred.

The planted washed sand has a homogeneous structure but contains inclusions of salts, humus and plant root particles, which are inferior to other building materials.

For this reason, it is used to build blends and landscaping processes where high quality is not required. Sometimes it is washed with hydro-mechanical devices for improvement, but it is also more expensive due to the additional energy consumption of building materials.

The place of storage and storage of sand obtained with a hydraulic alluvium: Alluvial map. The spread of water beyond its borders prevents the well from falling out of the local soil. Obvalyu excavators and excavators.

It would be a mistake to think that the sand was washed, alluvial and that the same material was washed.

They differ significantly:

The alluvial sand (river), which is extracted from the bottom of the river, contains polished rounded particles and is of high quality. Suitable for the construction, the glass production as well as for the establishment of a private house. The cost of 1 m3 of river sand in Moscow (including delivery) varies between 800 rubles.
The extracted sand is recovered by washing in the quarries. This is the most universal quality, it contains no clay, dust or organic substances, its edges are sharp and uneven, which is good for the adhesion of building materials. Suitable for various purposes: building construction, road construction. Like the river this type belongs to the most expensive sands, the price of 1 m3 of washed sand costs 800 rubles.
Flood - sandy soil in the form of excessively saturated quicksand

The sand is actively flushed with water using special hydro mechanical equipment, cleaning wastes and unnecessary item

To wash the sand you have to start your field, then wash the dough with high quality equipment and dry it with technical means. In several stages of the sand alluvium it is possible to obtain a high quality fine material for the construction of mixtures.

Washed sand is often used in the manufacture of paving slabs. Production of concrete mixtures with special resistance. in the drainage

Glass production; Manufacture of rings, blocks and other concrete products; Exterior design. It is often added to concrete mixes, line compositions, paints and gypsum. If you use sand mixtures for your own use, you must choose a concrete that is not inferior to the quality M300 and clear water. To accelerate the solution, plasticizers are added to the composition. Fine-grained quartz sand is used in road construction to produce wastewater and as an underlying layer.

The alluvial sand particles generally exceed not more than 0.6 mm, so that they can be used for plastering, laying high-quality road surfaces, the production of concrete and bricks.

In private buildings, the use of expensive sand is required for special permanent constructions: foundations, fences, solid walls, pillars, parking paths, swimming pools, fountains and others.

Modern construction requires high quality natural materials. Well washed particles do not adhere, they do not form lumps. The sand must be washed in places with low humidity and without strong wind. Otherwise, some sand will be deteriorated. It is possible to put sandy weight in canvas bags or bags. The sand package is 25 and 50 kg.

The prices of the sand depend on the type (river, laundry, seed), the filtration coefficient and the distance from the point of sale and the purchasing volume. The shipping costs are often included in the price. Coarse sand is cheaper because it is easier to handle.

There are big and small types of sand

The main feature of this material, the minimum content of mud and clay, does not exceed 0.3%. All elements of the alluvial mine sand do not exceed 2,2 mm. There are big and small types of sand. There are also differences in hues: from saturated gray to bright yellow. The stadium requires no special storage and transport conditions, it only needs to be protected from moisture and precipitation. Due to the minimal amount of impurities, the material is best suited for the construction of any complexity.

Types of alluvial land and quarry are commonly used

The impurities in the racing arena can be up to 30%, so their cost is much lower than the price of already washed sea or sand. The composition consists of up to a dozen different components: salt, humus, gypsum, root parts, large stones, etc. The main tone is clay (plastic sedimentary rock, which reduces the filtration coefficient and the strength of the concrete solution). A double treatment improves the sand quality and thus the costs. It uses untreated sand: as a foundation for the foundation, especially of low quality and for some road works.

Dry Cement Slag Process: In the dry process, each raw material is proportional to the desired chemical composition and is fed to a rotary ball mill or a vertical mill.

The most important raw materials for cement production are limestone, clay, sand, shale and iron ore. Limestone is usually extracted from the site, while other by-products from the site or nearby quarries can be recovered. Industrial by-products are another source of raw materials. The use of derived materials as a substitute for natural resources is a key element for sustainable development.

Content

1. History of Concrete and Its Ingredients.
2. Do you have too few options.


To understand the history of the concrete, we must first understand what the concrete is and how it is composed. Concrete is a building material that consists of cement, coarse aggregates, sand and water. The chemical process, known as hydration, solidifies the concrete after it has been laid, making it a very versatile and durable building material. Cement, the main constituent of concrete, is chemically composed of calcium, silicon, aluminum and iron. The materials commonly used in cement production are limestone, sand and clay, which contain all the chemicals needed to produce cement.

Cement consists of various components

Cement is made by extracting limestone from a quarry and transporting it by truck to a cement works where it is ground into marble pebbles. It is then passed through a blender where it is mixed with sand and clay, ground into powder and sent into an extremely hot rotary kiln as part of a process called sintering. The raw materials reach 2700 degrees Fahrenheit, which causes chemical and physical changes in the raw material and leaves the kiln in the form of clinker or large red glass ash, which are crushed to a fine gray powder. It is now Portland cement. Modern concrete component.


Concrete was invented in 1243 for the first time by the Romans. It is not clear in what form or from which components Roman cement is made. However, Assyrians and Babylonians used clay as a binder or cement in their concrete. In 1756, British engineer John Smeaton invented what we now call modern concrete. Smeatons concrete consisted of small stones as aggregates and activated bricks as a cement additive. The English inventor Joseph Aspdin invented Portland cement in 1824, the cement that dominates cement production to this day.

Concrete has existed since the Roman Empire, but not in its form, but since the birth of modern civilization. It has proven to be a reliable and versatile building material and is almost indestructible in the reinforced state. The United States has a specific industry of $ 35 billion a year, employing about two million workers in the United States alone. Concrete is not only a solid building material, it has also helped to build our economy and continues to grow. Concrete will occupy an important place in the construction industry in the coming years.

It is necessary to ensure high levels of cement in nature

As the largest carbon dioxide emitter (CO2), the cement industry, especially in Europe, has quickly tackled the problem of climate change. At industry level, the industry launched the Cement Sustainability Initiative in 1999. Many large companies have set voluntary emissions reduction targets. On the regulatory side, cement is one of the five sectors of the European Emissions Trading System (ETS).

In the first phase (2005-2007), the cement sector has far exceeded the ETS emission limits. However, as we approach Phase II (2008-2012) of the emissions trading scheme, there is increasing concern that reduction options will become increasingly constrained and more costly. The industry is concerned that the pressures exerted by the current EU ETS structure will result in exports of production and hence emissions beyond the EU's borders. In her view, her arguments are important for a new approach to emissions control in this sector.

To assess the impact of the EU Emissions Trading Scheme on the European cement industry, The Strategy Works conducted in-person interviews with key figures from the five major global players: Lafarge, Holcim, Heidelberg, Cemex and Italcementi. as well as a telephone interview. with Cembureau, the European professional association of industry.

The total turnover of these five companies in Europe is estimated at 26,000 million euros in 2006. Lafarge is a leader in the European cement market, with Holcim and Cemex competing for second place. , Together, these three companies account for around 70% of the turnover of the five companies surveyed.

The demand for cement in Europe is steadily rising by 2 to 3% per year. It is proportional to economic growth, and Lafarge points out that emerging economies today account for up to 80% of global demand, a trend that is expected to increase and change the global landscape of the sector. Industry efforts to reduce emissions are already ahead of the introduction of the EU Emissions Trading Scheme. Lafarge said it was the first cement producer in the world to set medium-term CO2 emissions targets in 2001. Other companies have done likewise. The five companies surveyed now have medium-term targets (2010-2015) for CO2 emissions. Public domain information, published in its corporate reports and annual reports on sustainable development, confirms that four of the five companies are reducing their emissions according to their goals.

The need for cement continues to increase

However, the introduction of the EU Emissions Trading Scheme requires mandatory limits for emissions from the sector. Under the EU Emissions Trading Scheme, national governments issue CO2 emission allowances (EUAs) based on emissions reported in recent years, a process known as "big" - fathers. "If they spend more than their allocation, they have to buy European units of account on the open market, and if they expect less, they can sell the surplus.

In the industry, Phase I generally saw generous allocations in Eastern Europe, but strict in the West, which is "not a fair field," according to Holcim. In general, companies were assigned orders for their expected Phase I emissions.

The companies were able to transfer their allocations between countries without having to trade in the open market. Three of the five companies seem to balance their allocation globally or net. Heidelberg "makes it country by country, because CO2 has the same value in all countries"

For its part, Cemex will take into account trade between institutions or countries in the second phase.
Cembureau reports that Phase I was "as usual" in the industry. There is no indication that the system has been shut down, but some factories have reduced or even stopped production due to the EU Emissions Trading Scheme. However, it is to be feared that the allocations for Phase II will be much stricter from 2008 onwards. In that case, the system could indeed cap production, as it may become uneconomic for European industry to buy the additional allowances needed to produce (and thus emit) more than the allotment.

There are several approaches to reducing emissions associated with cement production, but at least in Europe, two are essential. The first is to reduce the amount of clinker in the finished cement, which is referred to as "clinker factor reduction" or material replacement.

Cement is processed as needed, especially in size

Slag is the main constituent of the cement and provides the strength of the final product. However, clinker production is very damaging to the environment, both in terms of the fuel used to heat the ovens and the chemical process that converts calcium carbonate into clinker (which releases large amounts of CO2).

There are two main alternatives for clinker: blast furnace slag and powdered fuel ash (PVA or fly ash). Slag is a non-metallic byproduct of the steelmaking process, whereas PVA is waste that results when the combustion gases of a coal power plant are "cleaned up", effectively removing carbon dioxide means harmful gases.

The second method of reducing emissions is to use alternative fuels, including organic waste, feed and biomass. The savings in emissions are due to the fact that these fuels are considered to be "carbon neutral"; In net terms, they do not emit CO2 throughout their life cycle.

This leads to two economies. Firstly, CO2 emissions per unit of energy content are lower than for conventional fossil fuels, and secondly, indirect savings are associated with the recovery of this waste. If they were not used in the cement kiln, they would be buried or incinerated, which would lead to CO2 emissions to the atmosphere (although the EU Emissions Trading Scheme does not provide loans to avoid these emissions).

Substitution of materials is by far the most effective way to reduce cement emissions. In fact, about 60% of the emissions are emitted by the chemical processes in the furnace, the remaining 40% comes from the combustion of the fuel. Substitution of material points to these two sources, because at the beginning we need less clinker, which also means less fuel. The fuel substitute, on the other hand, only reduces fuel emissions.

Companies differ in that they follow these two paths. Holcim is the market leader in the spare parts sector. 27% of alternative materials, including gypsum, used in cement in 2006, compared to around 10% in most other companies. , Heidelberg is the market leader in the use of alternative fuels. In 2006, around 16% of total consumption was derived from sources such as biomass, tires and plastics.

However, existing emission reduction methods are limited. In general, the material exchange can not be more than 75% of the total composition of the slag cement and 25% of the fly ash.

Companies also state that quality is a limiting factor for fly ash: they are often contaminated and must undergo additional treatment before being used in cement. According to Lafarge, the problem of fly ash quality will become more important in the future as "energy producers will have stronger emission limits", which means that fly ash will increasingly contain pollutants. , Italcementi also points out that many of its customers are willing to pay more for higher clinker contents, which limits the rate of replacement of materials.

The cement process uses a roll crusher

Slag, on the other hand, seems to be limited. Cemex admits that "there is no indication of a possible increase in slag production in Europe". Therefore, only companies with long-term contracts have a guaranteed supply. Respondents were reluctant to disclose their sources of supply, but Lafarge claims to have signed long-term contracts with steelmakers. Holcim has a vertically integrated approach and "owns and operates slag granulation facilities in two steel companies", such as Arcelor in France and Salzgitter in Germany.

But even this limited offer is threatened. Heidelberg reports, "new mills do not produce granulated blast furnace slag, they are not part of the process". Italcementi envisages a two-generation problem (considering the life cycle of a 50-year-old steelworks), where "the bulk of steel production is still produced by the traditional process, which unfortunately applies to emerging economies such as China and less and less in Europe or North America, where new technologies recycle scrap. "

The industry is also facing increasing competition for CO2-neutral fuels. The electricity sector is distorted by competition. This sector receives so-called green certificates to burn renewable biofuels. Italcementi emphasizes "a double punishment" for the electricity sector. Electricity producers can afford to pay a higher price for biofuels because they pass them on to the consumer. They receive credits for the use of renewable energies, which certify that the electricity generated is "carbon-free". But they can also benefit from the sale of surpluses resulting from EU ETS permits.

Respondents estimated the average carbon price in Phase II at 25 EUR / t or even 35 EUR / t. 30 euros per ton of carbon corresponds to a price increase of the finished cement by about 30%. However, many customers value the brand, Lafarge said, "they will not accept such a price increase." The company warns against a future scenario that would drive the industry out of Europe: "This could lead to a shift away from shifting demand to non-European countries." Suppliers. This is the challenge we are facing now. "

Cembureau points out that the EU ETS is inefficient because it focuses on reducing CO2 emissions in Europe: climate change is "a global problem" for which the ETS seeks to "find a European solution".

There is a fear that the system will limit production in Europe if the price of carbon in Phase II rises as expected. It could then be economical to import cement or clinker from outside the EU, which would be contrary to the very purpose of the EU ETS.

Many companies say that this is not their intention, but in the worst case they could be the only option. Cembureau believes that "it would be the worst solution". The irony is that total emissions will actually increase due to emissions caused by cement or clinker transport.

An obvious solution is to change the way the EU emissions trading system works for the European cement industry and to rethink Grandmother's approach. Lafarge believes that "this is not the way to calculate future allocations ... it is imperfect".

Cembureau, like most companies, is committed to a comparative approach around the world, not grandfather. This would establish a reference level for emission intensity based on best practices against which performance would be measured. Because benchmarking is performance-based, efficient operation is rewarded. This is the opposite of the approach of the grandfather, who can reward the most serious polluters and punish the "good" by granting permits from past activities.

Cembureau proposes "to combine the cement industry around the world to define a specific performance to be achieved per ton of product".

Every future plan must be clearly global. The Association supports a system that "covers the OECD and major developing countries, or protects countries that can reduce CO2 emissions through competitive distortions"

Aggregates are made of different types of materials. The word "aggregate" in itself means a collection of different things, in this case stone, gravel, gravel, sand and slag. These materials often begin in the form of larger or larger rocks or compressed sediment layers, and some very heavy machinery require forming work to convert them into usable aggregates. After they have been crushed into small pieces with the help of crushing units, they can be used for road construction, buildings, platforms or other purposes like coal fot energy.

Table of contents

1. Coal Specification.
2. Hammers of hydraulic crusher
3. Crushing and grinding

Coal processing often uses roller stone crusher

Coal is an important source of energy. This makes paper an important raw material in metallurgy and the chemical industry. The recovered raw coal is too big. The coal is not treated and crushes the environment of efficiency and contamination. To use the coal more efficiently and less contaminated, it must be crushed and reduced to a reduced size. For a grain size of 5 to 20 mm for the gas stove, a grain size of 8 to 25 mm for the steam locomotive, a grain size of 10 to 20 mm for the industrial furnace. Coal-fired power plants require coal with a grain size of 5 to 20 mm.



Coal Mill Instruction

The coal milling machine consists of many types of mills. This coal mill is not used alone. They form a complete crushing plant with conveyor belt and vibrating screen. In the power plant, the coal gasification and the treatment of purified coal, the grinding process is the first step and the essential. The conveyor belt conveys natural coal evenly into the jaw crusher. After grinding, it passes into the impact crusher or the cone crusher for fine grinding. Final is eliminated by the projection machine.

In order to use coal more efficiently, efficiently and effectively, the coal has to be processed and ground in various sizes, grain size from 0 to 25 mm for the coal furnace, 25 to 8 mm for the steam locomotive, 25 to 6 mm For the industry, ovens and coal power stations need 0 up to 25 mm carbon. Therefore, coal processing in coal processing plant includes coal grinding and coal milling.

SBM coal machine
SBM has been a manufacturer of crushers and mills in China for 30 years. At any time we supply all types of crushers and mills for the quarry, the coal industry, the cement, ore and concrete industries.

Application of the coal crusher.
The boiler of the station is a boiler that supplies steam to the turbine generator of the thermal power plant, including the equipment of the boiler and its accessories. The fuel is burned in the boiler and releases heat energy and heat transfer through the metal wall of the boiler water to a certain pressure and temperature of superheated steam and then steam therein. Turbine, turbine-driven generators. The total thermal power generation capacity is around 70%, of which 80% is in China. Therefore, the boiler and its role in terms of energy consumption or the development of the economy have a significant impact. The fuel in the boilers of the plant consists mainly of coal. The design of the coal grinding plant is therefore the main grinding plant of the thermal power plant for grinding coal.

One stone crusher that uses hammer

In the construction industry, materials must always be broken. Therefore, you must use a jaw crusher such as hydraulic breaker, hydraulic breaker and demolition robot. The Grabengraben requires regular hydraulic equipment such as hydraulic hammers and hydraulic hammers to break up a large mass of stone or stone. To demolish buildings or level roads, we also need demolition equipment such as a two-roll crusher and a demolition robot.

On this page you will find our shredders. We mainly manufacture hydraulic hammers, hydraulic crushers, demolition robots and boom systems, as well as parts for demolition equipment. We have years of experience in manufacturing hydraulic equipment, so we know how to make high quality demolition equipment. In order to continue to offer the highest quality and most advanced equipment, we have analyzed the hydraulic equipment of other manufacturers and incorporated elements to improve their own hydraulic equipment. In this way we are confident to offer a hydraulic impact crusher, a demolition robot, a hydraulic crusher and a high quality boom system.

Crushing and grinding is often used for rocky tillage

The crusher is the exclusive composition of particles larger than 3 mm of the total emission rate of 50% or more of the crusher. The operation is often interrupted during feeding and probing in the size of broken, cracked and stingy grains. The road under the refractive power of the crusher can be roughly divided into two categories: (1) crusher; (2) rectifier. General switches for larger coarse grain materials, usually larger than 8 mm. Its structure is characterized by a certain distance between the fragments, they do not touch. The crusher can be divided into coarse crushers, crushers and fine crushers. In general, the grinders, the handling of smaller materials and the size of the product are good, up to 0.074 mm or more detailed. The structure of a broken part (or medium) is in contact, the medium used consists of steel balls, steel rods such as gravel or a mineral block. However, some machines also have crushing and grinding effects, such as grinding and conditioning of mineral materials from the upper limit of 350 to 400 mm, the product fineness being up to about 40% to 200%.



Road under the crusher from structural features to the classification, generally divided into six categories.

(1) Jaw crusher (Tigermund). The fragmentation function is to periodically move the jaw to the firm pressure of the jaw block in the folder where the ore is being ground.

(2) cone crusher. Pepita inside and outside the two cones between the fixed outer cone, the inner cone for the eccentric oscillation, the shirt in which the ore breaks or collapses.

(3) roll crusher. The mineral blocks in the two opposite rotating rolls are caught in a circle, mainly by the successive grinding effect, but also in the grinding function, the surface of the broken toothed roll is divided.

(4) vertical breaker. Nugget by the rapid rotation of the moving parts of the keystrokes were compressed. In this category the case can be divided into: sand making machine, hammer crusher; Crusher with impact crusher cage.

(5) grinding machine. The ore and abrasive were milled from the impact and abrasive media into the rotating cylinder by the milling media (steel balls, steel bars, gravel blocks or minerals).

(6) Other types of broken crushers.

A roller mill: Crush the material by rotating rollers

B, plate: vertical or horizontal axis of the disc, which rotates like the broken parts.

C, centrifugal mill. High-speed turned parts and media production capacity to complete the squeezing force.

D. Vibration rectifier. Made with a high-frequency vibration wave, so that the carrier and the materials to be produced touch and produce a grinding effect

Different types of crusher specifications, different uses. Currently selected crusher-jaw crusher broken or multi-stage plant; the standard cone crusher rotates; Small type with short cone crusher. Grind with a grinder, finely ground with a ball mill.