make use of energy saving coal

How Coal Forms?

As most people know, coal is composed of organic material from prehistoric times that have been altered chemically high pressure during the exposure time and very similar to the creation of oil in many ways. The accumulation of silt, manure and other organic ingredients are similar in swamps and bogs began millions of years ago. Tectonic changes and movements of the crust of land buried those areas, sometimes at great depths. The high-pressure environment combined with the heat of the Earth interior transformed organic matter by altering its chemical nature. First, it was turned into peat and peat was refined in the coal of different kinds. The quality of a deposit of coal is defined by the pressure and temperature along with time. A high quality coal has been subjected to pressure, temperature and transformation times since coal of inferior quality. The quality is usually associated with "organic maturity." Time deadlines for the creation of different types of coal vary widely. A deposit of peat can be created in as little as 9000 years, while anthracite requires millions of years to form. 

Low-rank coals 
The first stage in the coal maturity scale is called peat. Due to the acidic conditions the organic material is prohibited from decaying completely. Approximately 60% of the worlds swamp areas are peat. Due to very high water content and the presence of lots of non-carbon materials peat is not as energy-rich as brown coal and limited to local small-scale heating. The stage after peat is called lignite or “brown coal”, with a carbon content in the range of 25-35%. The water content is high (up to 66%) and the color can go from dark black to different shades of brown. This type of coal is mainly used for large-scale power generation. Next stage is sub-bituminous coal. The carbon content is 35-45% with a reasonable energy content. It is still quite soft and brittle with quite high water content (20-30%). Used in cement manufacturing and a large array of industrial processes along with power generation. 

High-rank coals 
The following stage forms bituminous coal. The carbon content of bituminous coal is around 60-86%, the rest is composed of water, air, hydrogen, and sulphur. This type is divided into two sub-groups called steam coal and coking coal. Coking coal and steam coal are the two types of coal that is most frequently traded. The steam coal is used as sub-bituminous coal in power generation. It has higher energy content than brown coal and contains less ash, thus making it an better fuel for coal-fired power plants.
Coking coal is a vital fundament in the metallurgical industry. High carbon content and low amounts of sulphur, phosphor and other unwanted materials are the typical properties of coking coal. 

The final type is called anthracite and consists of almost pure carbon (86-98%) together with some impurities. Barely 1 percent of all coal is classified as anthracite and it is mainly used in domestic situations as a smokeless fuel. It is harder to ignite than steam coal and the scarce supplies have greatly limited the uses. 

Higher carbon content than 98% leads to graphite or diamonds. Graphite is not used as a fuel, due to the problems of igniting it. Both graphite and diamonds have 
many uses in industry and are not treated as normal coal. 

Coal mining 

There are two forms of coal mining, mining surface and underground mining. Which method you use depends on the properties of coal seams. The underground mines are currently about 60% of the worlds coal production. But the worlds largest exporter of coal, Australia, 80% use of surface mining. 
Underground mines usually takes longer to complete and tend to make a greater portion of the vein of coal unusable, however, is the only viable option for coal seams fund. Two different methods of mining there, room-and-pillar mining and mining long. The first is cheaper, but leaves more coal unrecoverable, while the long-wall mining is the most expensive option but can recover more coal. The choice of the technique of mining is always based on economic considerations and differences in a single mine can lead to both methods. A problem with underground mining of coal is the risk of explosions. Coal seams contain small amounts of methane and other combustible gases that could be ignited by sparks, which leads to a gas explosion when the conditions are right. This is not a problem in the mining area. Surface mining can recover up to 90% or more of the coal industry. But it is only economic when the coal seam is located near the surface. Surface mining is simply a matter of the relocation of soil that discovers coal moving dirt covering. This time the damage in the area, but if adequate recharge and recovery takes place the mining can thoroughly restored. Coal that comes directly from a mine often needs to be treated in different ways. This treatment can be everything from grinding coal to fine powder in the complex process of chemical cleaning to reduce certain impurities. Coal cleaning can reduce the amount of ash more than 50% and thus reducing the amount of waste from combustion of coal.

Coal energy 
The coal has been a mainstay of electricity generation in the west and is estimated to be for the developing economies of today. Due to its cheapness, reliability and availability of coal is one of the few energy sources that can meet the growing demand for electricity in the world. 
The initial combustion of coal burning power plants of coal in pieces of a metal grate to boil steam that could be used in turbines. 
Today is the first coal crushed in a fine powder, thus increasing its surface and allowing it to burn faster. The dust has blown into a combustion chamber and is used to generate steam. 
The development of new coal-based power plants is closely linked to the gasification technology. Since a new concept uses coal gasification to improve efficiency and reduce emissions. 
The IGCC design (integrated gasification combined cycle) creates a synthesis gas from coal or any other source of carbon and burns at high efficiency gas, a gas turbine. It is also easier to clean impurities and harmful materials from synthesis gas in comparison with the cleaning of the exhaust steam from ordinary combustion of coal. 
Designs of Integrated Gasification Combined-Cycle typically offer efficiencies around 45% and reduce NOx and SOx emissions of 95-99%. Besides the development points to the net efficiency of 56% in the future. The IGCC-concept extends far beyond just the generation of electricity. A portion of synthesis gas can be diverted to a synthesis FT-stage and is used for the production of fuels and other chemicals. The synthesis gas can also be "changed" to produce pure hydrogen for a future hydrogen economy. The gasification of carbon dioxide makes the separation easier compared to regular coal combustion, and hence the potential to eliminate emissions of greenhouse gases looks very promising. 
Today there are about 160 plants IGCC worldwide in operation. The current reliability is considered a bit lower than other methods of coal combustion, such as supercritical pulverized coal combustion of coal and fluidized bed combustion. In addition the development is needed to make the technology of integrated gasification combined cycle, the chosen route of future energy companies of coal. 
However, the flexibility of an integrated gasification combined cycle, is a big advantage, especially for countries in need of electricity and fuels. In times of need of the plant can be focused on electricity generation and the free time of production can be shifted to the fuel via FT-synthesis. Analysts believe that the technology of integrated gasification combined cycle is very appropriate for developing countries that have indigenous coal and lack of funds to import oil or develop other energy sources.

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