The Story of Coal What is coal

The Story of Coal What is coal? Sometimes a miner finds a ferny leaf or piece of wood imprinted on a piece of coal. This helps to reveal the story of how coal was formed. Here in Britain, coal was formed at various times between 170 million to 300 million years ago. The rocks associated with the coal demonstrate that the major geological forces which have controlled the features of the earth’s crust have exerted their control also on the type of coal and the way it is presented in the earth. Major forces affect rocks at depth underground, causing crumpling, bending and breaking of the beds and cause mountain chains to be formed, sea levels to rise and fall and also give rise to earthquakes. Volcanoes have also left their evidence within coal seams and associated rocks. You can see the evidence of these vast disturbances most easily along the coast in the curving strata and breaks and faults of a cliff face. Forests from the Carboniferous Age which were transformed into coal over millions of years The rock sequences, which include coal seams, were first laid down as sediments washed down from upland areas by streams and trapped within lakes and sea covered basins. When these sediments filled the basin and land emerged, trees and other vegetation grew. Huge trees tumbled and were crushed; forests of saplings were engulfed or overlaid; ferns and mosses, grew through several centuries - then were swallowed or covered. Earth and rock and lava compressed trees, and other plants. They rotted and changed as bacteria attacked their remains. They were composted, condensed and compressed. More millions of years passed. They became coal. So what is coal? It is the woody (cellulose) part of vegetation formed by time, pressure, bacteria and other agents into a carbon rich mass. Types of Coal It is easy to imagine hundreds of variations in the ways in which coal is formed. For example, any of the processes that produce coal may take place more than once - and then layer upon layer of coal will be found. Again, some coal is deeply buried in thick seams hundreds or thousands of metres underground, but elsewhere it might be found only in thin layers on or near the surface. Yet again, the nature of the ‘coal' depends very largely on how the original matter was composted and compressed. Look at the table below and see how the hardest coal, anthracite, contains the most carbon and the least hydrogen and oxygen. Type of coal Lignite Cannel Bituminous Anthracite As a comparison Normal Woody Fibre Peat Anywhere Eire 53 60 5 6 42 34 Where found Bovey Tracey, Devon Most British coalfields Most British coalfields South Wales %Carbon 67 86 88 94 %Hydrogen 5 6 6 3 %Oxygen 28 8 6 3 Coal seams can be found near the surface or deep underground First find your coal Coal represents only a fraction of the rock beneath our feet so it must be prospected for. Exploration has found coal underlying large parts of Britain. The search for new supplies of coal begins with the geologist. His studies of the underground formations of a locality enable him to say 'I think we should do some trial borings here. The geological evidence leads me to expect to find a coal seam.' So a drill bores into the ground and samples of the strata are brought to the surface from various levels. If coal is found, further samples at increasing depths prove whether the seam is a workable proposition. if it is, a vertical shaft or an inclined tunnel known as a drift is sunk from the surface and radiating from this, a series of underground tunnels are driven. Most of our mines began in this way. Some large collieries have been established in recent years as a result of exploration. In addition to drilling boreholes, UK COAL’s geophysicists conduct other surveys to discover coal reserves including seismic surveys - using sound waves to indicate the presence of coal seams. Coal is also present beneath coastal waters and undersea mining has been carried out since the early 17th century. Coal is found in many parts of Britain Surface Mining Surface mining is a different method for mining coal from seams near the surface. Modern earth-moving machines like giant draglines and shovels remove the overlying earth, dig the coal and restore the topsoil at great speed. The land is then rehabilitated for future use - it can, for example, be for agriculture, country park, nature reserve, golf course or industrial or residential development. Coal around the world Coal can be found in every continent in the world Coal is found in every continent in the world, and like oil and gas is an internationally traded commodity. In 1999 the leading world producers of coal were as shown in the tables shown below. Total Global Hard Coal Production: 1998 3,656 million tonnes (Mt) 1978 2,626 Mt - 40% growth over past 20 years Worlds top 10 producers are as indicated in the following Bar Chart As a comparison Great Britain produced 41.2Mt to year ended March 1998 Total World Primary Energy Consumption (% by fuel) Coal provides around 26% of global primary energy needs and generates about 37% of the world’s electricity of the total 505 million tonnes of hard coal traded internationally in 1997, some 60% was thermal coal and about 40% coking coal. Coal in Electricity Generation: coal is the major fuel used for generating electricity worldwide - countries heavily dependent on coal for electricity include (1998): By comparison Great Britain generated 38% of its electricity from coal to year ended 1998 Current coal reserve/production ratios confirm over 200 years of resource availability. Of all the fossil fuels, coal is by far the most plentiful in the world. It has been estimated that, as at 1996, there are around one thousand billion (1 x 1012) tonnes of total coal reserves economically accessible using current mining technology, approximately half of it being hard coal. In Great Britain there is in excess of 400 million tonnes of proven coal reserves identified, which at present extraction rates would last approx. 20 years. Coal made Britain great Britain's Industrial Revolution in the 19th century which set the pattern for our own prosperity was made possible by unleashing coal energy. Opportunities in a lump of coal spurred the inventors and engineers and led to the new factories, machines and concepts of production and transport of the Industrial Revolution in the 19th century. Beyond everything, coal provided the steam power for engines that worked machines, for locomotives to carry people, raw materials and finished products and for the first production lines. George Stephenson's Rocket - powered by coal ! Gas from coal lit towns, workshops and homes for people who previously spent much of their lives in semi-darkness. It gave the power to travel fast, do many things at once, and exert forces greater than man or animal. Power to produce and use still more coal... Through the use of coal Britain led the way in the industrial revolution. Partly this was by being 'an island built on coal' - and because the British had the skill and ingenuity to win the coal and develop its uses faster than other nations. It also helped by harnessing the genius of the inventors, engineers and industrialists of the age. Ironbridge, Shropshire - A symbol of the coal powered Industrial Revolution It could be said that Industrial Revolution is still with us to this day and will carry on forever. It can be shown that even today, despite the development of alternative energy sources, coal produces about one third of the power Britain uses. Coal, which inspired and powered the Industrial Revolution of the last three centuries, still plays a vital role for our country today. How mining began - and grew Coal was in use before the Romans came to Britain. We can assume coal exposed on the surface was excavated first, and then in an effort to continue working the seam, the first miners had to follow it underground. Here is a story that is almost certainly true. A caveman gathered sticks to make a fire and rocks to make a fire grate. Some of the rocks were black. When he set fire to the sticks, he was astonished to find that the black rocks were blazing merrily too. He had discovered coal. We would like to prove this story true with archaeological evidence but we cannot. There are no clues to the use of coal in the Stone and Bronze ages, nor can we be sure that the Israelites or ancient Egyptians used coal let alone mined it. We do know, however, that even before the Roman invasion Britons used and mined coal. Flint axes have been found embedded in coal. Doubtless the Romans learned about coal from the Britons - we have evidence of coal stores all along the chilly length of Hadrian's Wall. At various places along our shores, coal was picked up on beach outcrops. When this was gone, the coal-seekers hacked away at the beach to uncover the seam and follow it inland. If they were lucky, they were able to quarry the coal out on the surface. But generally the seam led them underground. They had to dig in earnest and coal mining began. Bell pits The first simple coal mine the bell pit, 'mechanised' with a windlass powered by horses to draw the coal up. We know that monks got their coal this way and we know just how they used it. Room and pillar The simple bell pit had hazards, such as ‘cave-ins’ and failing rocks and earth. So when mining began to develop the first problem to be solved was that of keeping the mine from failing on one's head. The room and pillar mine was the first answer. A bell pit was dug and squared off at the bottom to form a 'room'. Another 'room' was added next to it and another after that. The walls between the 'rooms' were pillars of coal left standing to support the roof. This system was used for centuries. There are many references to such mines from the 13th and 14th centuries on. We know that the mines were lit by rush dips and ventilated and kept as dry as possible. Longwall mining One defect of room and pillar mining was its wastefulness because it meant pillars of valuable coal had to be left. The need to get nearly all the coal out led to the introduction of longwall mining, which was common practice from the 17th century onward. A team of miners worked with picks and shovels hewing out the coal on one side of a tunnel in the coal seam called a 'face', erecting timber roof supports as they moved forward. The space behind them was filled with stone waste and spoil - 'goaf'. A road was kept open through the goaf for access to the face. Inventors and Coal Coal would not have changed the face of Britain without the inventors who solved mining problems and released the energy locked in the coal. Thomas Savery developed the 'miners' friend', a steam engine that could pump water at 270 litres a minute (1698). Thomas Newcomen developed the beam engine, the first steady-running atmospheric engine (1705). It was used particularly for pumping. It was said Newcomen saved the mines and the nation's prosperity. A Newcomen beam engine George Stephenson made a steam pump and engine that solved the problem of pulling tubs of coal from coalface to pit bottom. He also improved colliery railways and built the first practical locomotives. James Watt made the separate condensing engine, a greatly improved and more powerful Newcomen engine (about 1770). This engine was a prime mover - it could lift weights and drive mechanisms. James Watt Richard Trevithick further improved steam engines to use high steam pressures (early 19th century). These engines raised coal and men from mine to surface and made possible the first pit railways. Richard Trevithick's high pressure steam engine Gas and iron William Murdoch, once an employee of James Watt, baked coal in a cast-iron retort and drew off coal gas - the same gas by which our streets were lit and dinners cooked. Abraham Darby invented the blast furnace and so virtually started the Victorian Iron Age (Bessemer and Siemens introduced the Steel Age about 1850). Ventilation Carlyle Spedding devised systems using partitions, barriers and doors to direct airflow for safe ventilation of mines. He also worked on lighting systems for pits. Sir Humphry Davy invented the safety lamp - a flame burning inside metallic gauze that cannot ignite the methane gas (firedamp) in mines - that was named after him. A flame safety lamp And one more recent inventor... James Anderton invented the ‘Anderton shearer’ - the forerunner of the modern coal cutting machines ‘the power loader’ used in modern mechanised mining. A Meco Moore coal cutting machine circa. 1950's Coal in Britain today The first mines were small holes in the round. Today neat surface buildings and lawns give no sign of the intense, widespread activity underground. A coal mine in the beginning was probably a bell pit owned or used by a few men. During the Industrial Revolution coal mining - like every other industrial activity - suddenly assumed new significance. Men became millionaires on coal. Others worked their short lives out in the mines, to die young of the dust disease pneumoconiosis or injury. During this century, the battle for coal involved many other battles with wage disputes and strikes, lockouts, disasters and reforms. In 1947 the coal industry became the property of the State - it was nationalised. The owners were recompensed for the value of their mines and miners worked under public ownership instead of private companies. The National Coal Board (latterly known as British Coal) was set up to manage this vast industry on behalf of the nation. However the demand for cheaper energy forced major restructuring of the coal industry. Decisions to return the coal industry to private hands were made and in the late 1980’s and early 1990’s, British Coal undertook a period of mine closures in preparation for offering for sale the most economically viable coal mines. UK COAL PLC (formally RJB Mining PLC) was the successful bidder for the largest group of mines, all of which were situated in England. Other coal mines which were located in Wales and Scotland were purchased by different companies. Under the ownership of UK COAL , the remaining 13 underground coalmines, have continued to improve productivity and cut the cost of production. British coal mines, achieve the most economically produced coal in Europe, with a level of productivity of 3,200 tonnes per man year. This is six times more efficient than any other producer in Europe, and places UK COAL at a competitive level with the largest of the world coal producers. From men to machines To understand the scope of mining now it helps to look back and compare. In the 17th century Newcastle mines were at most 125 metres deep, about as deep as St Paul's Cathedral is high. In the 18th century, some mines went as deep as 300 metres, around the height of the Eiffel Tower. By the beginning of the last century some mines were 800 metres deep and the increased power available from coal power itself, was used to remove the coal, ventilate the mine and pump out water. The deepest mines today are more than 1,000 metres deep. But it is during the last generation that mining has changed most radically. The mines of all preceding centuries and much of this century were filled with people and animals, working. The mine of today has no one hewing the coalface - scores of men are replaced by a handful operating machines. Where there used to be many collieries, most of them small, we have today a deliberate concentration of very efficient, highly mechanised mines. Machines now win virtually all the coal from British mines more safely than ever. Mining of coal near the surface is another major subject on its own. It is an important part of the industry and UK COAL Surface Mining, plays a responsible role in this form of mining. Surface mining sites provide low-cost highquality fuel and profits that assist deep-mining activities. On surface mine sites, the topsoil and subsoil’s are separately stripped by machine and placed in baffle mounds around the site to screen the workings. As coal is exposed it is lifted by excavating shovels and transported to a disposal point for sizing, screening and blending for power stations, industry or homes. It is often used for blending with lower quality deep-mined coal to improve quality. A modern dragline situated at a surface mine site A measure of how surface mining mechanisation has advanced is that excavators 50 years ago were limited to a bucket size of less than one cubic metre while today there are draglines with bucket capacities ranging from 10 to 27 cubic metres. Compared with a deepest excavation of 30 metres in 1948, today depths of 80 metres are common and the deepest so far has been 215 metres. Great care is taken to minimise disturbance during operations and the land is imaginatively restored for other uses when mining ends. Coal by wire Most of the output of UK COAL goes to power stations, and as a third of our electricity is still generated from coal you can fairly call it coal by wire.You can transform coal into many different products - but quite the most important transformation is from coal to electricity. No other form of energy can approach electricity's versatility in homes, offices and factories and this vital need for electricity will increase. Power stations use coal to heat boilers to produce steam which, in turn, is used to drive turbo-generators. In the most modern power stations, all these operations are completely automatic. The coal is pulverised to a powder that can be fed to the boilers pneumatically, as if it were a gas. The boilers are massive - some can convert more than a million pounds of water into steam each hour. Major power stations receive coal on a 24-hour, seven-days-a-week schedule. Electricity not needed locally is fed into a national grid or 'supergrid' carrying power all over the country through about 13,000 kilometres of high-voltage transmission lines. With the increasing awareness of the effects to the environment of the burning of coal and other fossil fuels, new technologies and methods of combustion are being researched and developed to make coal a more efficient and cleaner fuel for power generation. UK COAL has proposals to build an Integrated Gasification Combined Cycle (IGCC), electricity power generation plant sited next to Kellingley Colliery, West Yorkshire. This plant would showcase this new form of clean coal power generation technology and stimulate take-up of this technology to replace existing coal burn capacity and future gas and nuclear generation when these stations reach the end of their natural lives. Kellingley IGCC schematic Smokeless Fuels Coal and fuel manufactured from coal, which can burn smokelessly, has made Britain's towns and cities cleaner and ended the smog’s once caused by smoke. Smokeless fuels can be divided into two main categories: Natural Smokeless Fuel and Manufactured Smokeless Fuel. As the names suggest one of these fuels is a product of Mother Nature, the other is made as a result of processing the coal. Anthracite coal is a naturally smokeless fuel and is still mined in South Wales today, albeit in limited quantities. Coalite or Phurnacite are examples of manufactured smokeless fuels. Although different processes are used to produce a smokeless ‘coal’ the majority of these are based on reducing the volatile content (the gaseous component of the coal that creates the smoke), pulverising, curing and binding the coal/anthracite into a briquette. The warm cosy glow normally associated with coal can be enjoyed via an open fire, a room heater, a stove, or a cooker when using smokeless fuels. Coke Coke was the first man-made smokeless solid fuel gained from coal. It is produced by heating coal to a certain temperature in the absence of oxygen. This liberates by-products for use elsewhere and at the same time gives silverygrey, clean and economical solid fuel for the home and many grades for industry use. Coke is sized by taking it over large screens to grade the product for industrial use. Coal can be made to suit special varieties of coke for different uses in industry by blending various types of coal. One example is for sugar refining. The Monckton Coke and Chemical Company, a subsidiary of UK COAL, manufactures and sells coke products in the UK’s industrial and domestic markets. In addition is also exports coke to the producers of special metals in Scandinavia. Coal's treasure trove The wealth you can get from coal and just some of the many things that can be made from coal and its byproducts. Hold a small piece of coal over a Bunsen burner and you expect certain things to happen. One piece of the coal may catch alight in a tarry, smoky sort of way. Other pieces will change appearance as smoke is released. There will be a pleasant smell and an unpleasant mess of smuts and smoke. This imperfect burning of coal opened the door to a treasure trove of by-products. The range of by-products that can be obtained from coal is generally divided into two families. The coal itself releases some by-products - such as thick brown smoke containing gas, tar and ammonia liquor. Example: - ordinary tar. The others result from further chemical and physical treatments of the by-products, producing explosives, cleaning agents, plastics and much more. Example: - disinfectant fluid. The Monckton Coke and Chemical Company manufactures and sells smokeless fuels, foundry and industrial coke and by-products including coke oven gas, tar and benzole. A Smokeless Living Fire Smokeless fuels and modern coal burning appliances combine a cheerful living coal fire with an efficient, clean burn. The beauty of the simple coal fire has been appreciated from the first but the old-fashioned open fire was wasteful. Probably 80 per cent of the heat went up the chimney. It demanded frequent attention and it made smoke which polluted the air. Even in days when Britain had a much smaller population and coal and labour were cheap, it was realised that it was silly to burn coal in an open grate. The Victorians developed some excellent grates - including one with heat-radiating metal bars, a deep pit to hold several days' ash and a controlled convection and chimney-draught system. But coal was so cheap, this sort of grate remained just a good idea. However, after the Second World War, coal was scarce and waste was intolerable. Fogs became smogs. Far fewer people had servants to service the fires. Something had to be done. Householders began installing slow burning 'all night' fires. With the new grate they adjusted a lever to cut down the amount of air reaching the coal - and the fire kept alight all night and burned more efficiently all day. But these were not the complete answer. Although they burnt smokeless fuels remember the Clean Air Act - there was still too much heat going up the chimney. Two things were necessary: better fuels and better appliances to burn them. The fuels Homefire, Phurnacite and others, have already been described. All are smokeless and are manufactured coal products, as distinct from raw coal. Many families have central heating and if they want economy and efficiency they may well have a coal-fired system. In a small house a room heater with a back boiler may be enough to warm the room and several radiators. Some room heaters and central heating boilers burn inexpensive ordinary coal smokelessly. Warmth you can see Modern open fires are labour-saving and burn smokeless fuels. Fitted with a back boiler, they can also heat all the hot water for a family as well as a few radiators. People who love a fire they can see and yet demand very high efficiency can have it, thanks to armoured glass. Heat-storage cooker/water heaters are cherished by good cooks - two hotplates, two ovens, very hot and simmering hot. They heat water and warm the kitchen too. A modern open fire burning smokeless fuel Down a modern mine What it's like to go down a modern mechanised mine. No two mines are exactly alike - but what they all have is a high degree of mechanisation. The most important consideration is that of safety. So first, pick up your personal protective equipment before going underground. This includes your helmet, ear defenders, kneepads, gloves, safety glasses, battery lamp and self rescuer - a device you are most unlikely to need but must be carried and would allow you to breathe if there was a fire causing carbon monoxide in the mine air. Swipe your pass card at the shaft side safety barriers, so that the safety department knows you are going underground. Before entering the cage to descend into the mine, you will be searched for ‘contraband' (cigarettes, matches or aluminium foil), as these items are not allowed underground. Into the two-deck cage, and descend down the mineshaft, very quickly to the pit bottom. The typical layout of a coal mine underground An underground locomotive used to transport men and materials At the pit bottom, up to 1,000 metres below the surface, you board a diesel or, battery powered locomotive train, which will take you to the outbye end of the coalface district. You may have to walk or ride on a conveyor belt to a point nearby to the actual coalface. At the coalface itself, notice the bank of powered roof supports, the armoured face conveyor, and the coal-cutting machine. These are the three main components that make up a coalface. The coal-cutting machine ‘the power loader’ comprises a main machine body, which houses the electrical switchgear, traction units and hydraulic pumps. At each end of the machine there is a ranging arm, each fitted with a vaned drum with steel picks. These drums rotate at between 30 to 40 rev/min and cut the coal out of the coalface. The power loader is mounted on the armoured face conveyor and moves backwards and forwards along this conveyor cutting the coal from the coalface and loading it onto the conveyor. Once the coal has been loaded onto the armoured face conveyor, the twin chains fitted with scraper bars, which run inside the conveyor, carry the coal along the coalface, discharging the coal onto the ‘stage loader’. A radio controlled power loader cutting coal on a coalface As the power loader reaches one end of the 250-metre coalface. The conveyor and powered roof supports are individually ‘advanced’ forward ready for the power loader to make another cutting run along the coalface. Time for us to leave the coalface and follow the coal. As already described, the coal is delivered from the armoured face conveyor onto a much shorter armoured conveyor called the ‘stage loader’, which delivers the coal onto a belt conveyor, which takes the coal away from the coal production district, and along several other belt conveyors to the pit bottom. On its journey to the pit bottom, dust is kept to a minimum by the use of water sprays. The coal from our coalface, and other districts under development at the mine, is transported by conveyor belt to the pit bottom. The coal is loaded into bunkers, with a capacity of 600 to 900 tonnes. The coal is then discharged from the bunkers into coal winding skips, which carry payloads of up to 22.5 tonnes of coal, and are raised though the mine shaft from the pit bottom to the surface of the mine. Drivages To be able to cut the coal from a coalface, roadway’s firstly have to be driven through the strata to ‘block out’ a parcel of coal. This parcel of coal some 1,000 – 2,000 metres in length, and 250 – 300 metres in width, becomes, the next coalface to enter into production. The machines used to cut these roadways are called drivage machines. There are two types of drivage machines normally employed in roadway developments. The first type is a ‘Boom’ type machine which has a rotating head fitted with picks at the end of a boom. The boom is positioned by means of hydraulic cylinders, up or down, left or right, to cut out the profile required for the roadway. This type of machine is usually used to drive the arched roadways, used as the main colliery roadways and transportation routes. The second type of machine is a ‘Continuous Miner’; this has an elongated cutting drum, the same width as the machine, and is pivoted at the opposite end on a support arm. The support arm is raised up or down by means of hydraulic cylinders, and cuts out a rectangular shaped profile, which is normally supported by roof bolting. This type of machine is usually employed to undertake the coalface development drivages. A Continuous Miner used for underground roadway drivages Mining transformed What you see on your underground visit is the result of mining's own Industrial Revolution of recent years, which continues with the extension of remote and automatic controls. In 1947 the average output for each man employed in the coal industry was little over 1 tonne each shift. Today the figure is more than ten times as much. Mechanisation has made a great difference. Look at the mining methods of a few years ago. To get the coal, miners used explosives, picks and shovels and wooden pit props were used. The explosives broke open the coalface, the pick and shovel hacked the coal out and loaded it on a crude mechanical conveyor and the props kept the roof and walls from collapsing. A coalface circa. 1950’s Compare with today's method. Instead of large groups of miners, now one or two miners operate machines like the power loader, which cuts a clean, geometrical coalface and loads the coal it has cut onto the armoured face conveyor. This can articulate forward into the newly exposed area behind the power loader with no pause in the flow of coal. And the pit props? Now there is a line of self-advancing powered roof supports in the modern mine. They consist of banks of steel beams carried on hydraulic legs, which are electronically operated and work at hydraulic pressures of up to 340 bar. The powered roof supports in turn are attached to the armoured face conveyor by hydraulic rams. The coalface is cut by the power loader, which moves along the armoured face conveyor and the powered roof supports ‘advance’, automatically adjusting themselves to the correct height and the load they must bear to support the newly exposed roof. This provides an envelope of steel to protect men and machines. Push button mining Today’s control systems have been integrated, by incorporating the position of the power loader on the coalface, into the powered roof support control computer system. This enables the automatic operation of the power roof supports determined by the position of the power loader, this is commonly known as ‘Chock Initiation’ (‘Chock’ being an alternative term for a powered roof support). Further more recent developments that have taken place in underground coal mining are :2 leg powered roof supports, which are electro-hydraulically controlled. Power roof support high-pressure hydraulic pumping systems. Radio control of power loaders. Power loader on board health monitoring / diagnostic packages. Data transmission of coalface information to the colliery surface offices. Electrical variable speed drive systems for armoured face conveyors and belt conveyors. All these developments are gradually being integrated into the coalface engineering package, to give safer, higher but more consistent output from the coalface. A Modern "2 Leg" powered roof support Remote control, automation and monitoring, are widely throughout the mine, with all information about a mine at work, being fed into the computer network system, and can be monitored at the control room on the surface, and also the relevant engineering departments and managers. Mining engineers call this system ‘MINOS’ - short for Mine Operating System. These systems, which improve efficiency and safety, already control transport systems and monitor temperature, mine gas concentrations and ventilation underground. Similar systems are also being deployed to monitor, and in time, to control mining operations at the coalface. In addition other computer packages such as ‘JDE’ are used for stores ordering and planned maintenance systems, ‘COMPASS’ for time and wages management. Underground operations monitored and controlled from the colliery control room Coal Preparation Customers' coal-burning equipment demands fuel of particular qualities and colliery preparation plants provide it. Not everything that comes out of the mine is coal. Mixed with the coal are shale, rock, dirt and bits of wood and metal. These are removed in the Coal Preparation Plant, a clean and modern building near the mine itself. Computers automatically control it and a small number of technicians supervise all the operations. A huge magnet removes metal from the coal passing beneath it. Other machines wash, sort and separate until only coal remains. Giant screens sieve the coal into various size grades, ranging from large coal to dust. Size is very important. In your home, modern appliances are designed to burn a particular type and size of fuel and the industrial users of solid fuel are even more demanding. Whether they buy coal for space heating, making electricity, steam raising or industrial processes, they want to know exactly what they are getting and how the fuel will behave. Not only are the size and the form of the fuel supplied important - so is the way in which it burns and the ash that it leaves. Coke oven operators, for example, demand and get coals with a very low ash and moisture content. In short, today coal is produced and prepared for sale by mechanical or automated means and sold to customers whose equipment will take in and burn the coal mechanically, often by automation. The coal is graded, sized, blended and processed to fulfil precise requirements and is subjected to strict quality control. A Modern Aerial Photo of a Coal Preparation Plant A Internal Photo of a Coal Preparation Plant Transporting coal How the huge physical bulk of millions of tonnes of coal is delivered to customers all over Britain. Transporting coal by canal barge Loading coal into locomotive wagons At most coal mines the newly won coal is handled by belt conveyors to the pit bottom, and then in coal winding skips to the surface. In drift mines where access to the pit bottom is through a sloping tunnel from the surface, belt conveyors carry the coal all the way from the coalface to the surface. From the colliery surface to preparation plant the coal is carried by belt conveyor and from the coal preparation plant the railways take over. Thousands of wagons are used on the British railway system to carry coal from the colliery to marshalling yards and from there to individual Power stations. Power stations take over 90 per cent of all the coal UK COAL produce. Railways carry huge tonnages in merry-go- round trains, which shuttle back and forth between mines and power stations. Coal wagons designed for mechanised handling, are part of the railway system and every week carry more than half a million tonnes to power stations. Lorries, ships, and river and canal barges also play their part in distributing coal round Britain for homes, industry, public buildings and other customers. Special-purpose colliers and lighters transport coal by water. Coal research New, cleaner ways of using coal are being developed by scientists. Research is important because coal will be needed next century when offshore supplies of oil and natural gas decline. But the coal will have to be used in ways that do not harm the environment. Fluidised combustion Some industries are already using a more environmentally friendly combustion system called fluidised bed combustion. When air is blown through sand it looks as if it is boiling - in fact just like boiling water. If it is heated and coal added, the coal burns and keeps it hot. This method of burning coal can take out nearly all the acid rain compounds usually made when burning coal. Coal Combustion Research Electricity from coal Three quarters of all the coal burned in the UK is used in power stations to generate electricity, but only one third of its heat is converted into electricity, the rest being lost in the cooling towers. Today scientists are working on new, pollution-free, ways to make electricity from coal using much more of the coal's heat. Coal refinery Oil and gas can also be made from coal and experiments have been carried out to ensure that we can do this cleanly and safely when it becomes necessary. Coal and the environment The coal industry's efforts to conserve or improve the environment are worthy of praise. Like every other major activity of man, coal mining and burning have an effect on our surroundings and the British coal mining industry’s efforts have been directed for many years at keeping the impact of its activities - both deep mining and surface mining - to a minimum, and enabling coal to be clean, efficient and safe to use. The industry has vast experience in minimising the effect of its operations to be a 'good neighbour' to the surrounding community and in restoring sites to productive use when mining ends. This includes places that were derelict eyesores before surface mining removed coal near the surface and the area was restored to high standards - for uses including farming, forestry, country parks, nature reserves, sports grounds, golf courses, industry and housing. UK COAL has close links with environmental experts outside the industry and has sponsored environmental research projects. Rainton Meadows County Durham, A fully restored Surface mining site Coal today and for tomorrow The coal industry is still a very important business in this country. The then National Coal Board - which became British Coal - was set up on January 1 1947 to manage a vast coal mining industry on the nation's behalf. In December 1994 UK COAL (formally RJB Mining PLC) successfully acquired the major bulk of the English coalfields upon the privatisation of British Coal, becoming the Europe's largest independently owned mining company. You can look ahead to coal tomorrow. We in Britain have enough coal reserves to satisfy our needs for generations at present rates of mining - long after oil and gas supplies have run down. Fortunately almost anything that can be processed from oil can be made from coal and when natural gas from the North Sea runs out, coal can again become the main source of gas supply. The industry is well advanced in developing new technology in mining and new processes for coal use, with care for the environment very much in mind. Despite the growth in use of other fuels, which has resulted in a reduction in the industry's size in recent years, it remains a very substantial business. Coal supplies about one third of the heat and energy we use. Then there are chemicals, plastics, disinfectants, medicines, road surfaces, paints, fertilisers and many other things made with or from coal by-products.