Of course, you know that coal is used as fuel, both in the home and in industry. Coal was the first fossil material that people could use as fuel. Coal helped to make the industrial revolution. In the nineteenth century a lot of coal was used for transport. In 1960, the coal was given about half the world's energy production. However, by 1970, its share had fallen to one-third of coal as fuel has pressed other sources of energy, particularly oil and gas.
However, the use of coal is not limited. Coal is a valuable raw material for chemical and metallurgical industries.
Coal is coking coal. Coke plants consume up to 1/4 of the extracted coal. Coking is a process of refining coal by heating to 950-1050°C without oxygen. Decomposition of coal formed solid product - coke and volatile products - coke oven gas.
Cox is 75-78% by weight of coal. It is used in the metallurgical industry for smelting iron, and also as a fuel.
Coke oven gas is 25% by weight of the processed coal. Volatile products formed during coking coal condense water vapor, resulting allocate coal tar and tar-water.
Coal tar is 3-4% by weight of coal is a complex mixture of organic substances. Currently, scientists have identified only 60% of the components of the resin, and it is more than 500 substances! From the resin get naphthalene, anthracene, phenanthrene, phenol and tar oil.
Tar-water (she is 9-12% by weight of coal) by distillation with steam emit ammonia, phenols, pyridine bases. Of the unsaturated compounds contained in the crude benzene, get coumarone resin, used for the production of varnishes, paints, linoleum and rubber industry.
From coal receive artificial graphite.
Coal is also used as inorganic materials. From coal processing in industrial scale extract such rare metals as vanadium, germanium, gallium, molybdenum, zinc, lead, and sulfur.
Ash from coal combustion, waste production and processing used in the production of building materials, ceramics, refractory materials, alumina, abrasives.
In total, by processing coal can be obtained over 400 different products, which cost 20-25 times higher than the cost of the coal and by-products produced at coke plants, exceed the cost of the coke.
By the way...
Coal is not the best fuel. He has a big drawback: its combustion produces a lot of emissions, both gaseous and particulate (fly ash), polluting the environment. In most developed countries, there are strict requirements on the level of emissions permissible by burning coal. Emission reductions achieved through the use of various filters.