As the world moves to combat climate change, it’s increasingly doubtful that coal will continue to be a viable energy source, because of its high greenhouse gas emissions. But coal played a vital role in the Industrial Revolution and continues to fuel some of the world’s largest economies. This series looks at coal’s past, present and uncertain future, starting today with how it’s formed.

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Love it or hate it, coal played a crucial role in launching us into the modern world by fuelling the Industrial Revolution. The byproducts of that role were, of course, the rise of greenhouse gases in our atmosphere and dangerous levels of air pollution in the big coal-fuelled cities.

But despite its insidious influence on the climate and our health, coal has a lesser-known positive side to its otherwise dark soul. It has provided us with some stunning fossils.

Geologists have known for centuries that coal is an accumulation of plant material that, once buried in the Earth’s sedimentary layers, gets compressed by gravity into a denser, compact form. Yet, in recent years, scientists have hotly debated the early phases of coal formation.

The discussion hinges on whether coal formed due to the absence of certain organisms that actively break down the woody tissues of dead trees, or whether other non-biological factors were the reason.

Contested origins

Coal starts its cycle of formation with the accumulation of plant material in swamps or bogs. Decaying plant matter that builds up at the bottom of bogs or swamps is called peat. After other sedimentary layers bury the peat deposit, the weight of these sediments builds up and compacts it.

Other chemical and physical processes also alter the peat, including pressures exerted by tectonic forces as continents move and crash into one another. These processes eventually turn the layers of compacted peat into rock we can mine.

Pure black coal, richer in organic carbon and tempered by heat and pressure, is called anthracite. Brown coal, or lignite, is mostly just compressed peat and has more sediment mixed in with plant matter.

Coal has formed as very large deposits at certain times in Earth’s prehistory. So much so that Reverend William Conybeare, the esteemed British geologist of the early 19th century, first named the Carboniferous or “carbon-bearing” period (359 million to 299 million years ago) after the distinctive coal deposits of Britain in his book of 1822.

These great coal swamps formed in what were the Earth’s first great forests. They were home to many varieties of giant amphibians and early reptiles and huge insects, as global oxygen levels were very high at this time.

For many years, scientists believed that coal formed in such large deposits at these times because certain fungi that helped break down the lignin, or woody tissues, had not yet evolved. The molecular clock estimates for the appearance of these fungi, called Agariomycetes, suggest they should appear in the Permian period (299 million to 252 million years ago), after the formation of the vast Carboniferous coal deposits.

A new theory

But this doesn’t account for the huge amounts of coal that formed in much later geological periods, such as the Cenozoic, over the past 65 million years. And a new study, led by Matthew Nelsen of Stanford University, takes issue with this model, as well as presenting a new hypothesis for coal formation.

The study authors argue that coal formed in the Carboniferous period consists dominantly of plants such as horsetails, or Lycophytes. These trees grew to enormous sizes and their periderm, or outer cuticles of the trunk, lack lignin, so wouldn’t be affected by the absence of lignin-degrading fungi. Their argument points to the biochemical composition of the plants having little to do with how coal accumulates.

The distribution of coal deposits through time is seen in the chart below of the estimated total volume of coal in North America. Large deposits of coal also accumulated during the age of dinosaurs (Mesozoic Era, from 252 million to 66 million years ago) and during the first half of the Cenozoic period (between 66 million and 30 million years ago), well after the predicted first appearance of lignin-degrading fungi.

The paper argues that tectonic factors are the most likely reason such big coal deposits built up at certain times. Large basins fill up with thick sedimentary piles when continents collide and mountain-building occurs. Some really excellent fossils have been found in such coal deposits, although the acidity of coal often dissolves bones.

The best-preserved fossils are those caught in the cleaner sediments laid down by streams between coal seams. Such fossils are routinely uncovered as part of coal mining. Several of the large fossil amphibians that lived in the Carboniferous swamps have been found this way.

A famous site at Nyrany in the Czech Republic was discovered because the director of the natural history museum there had coal delivered to heat his room. Splitting the coal sometimes yielded well-preserved fossils of early amphibians, so he could add scientifically significant specimens to his collections without leaving his office.

Perhaps the most famous fossils found in a coal mine were uncovered at Bernissart in Belgium. Many skeletons, representing 33 individuals of the large plant-eating dinosaur Iguanodon, were found there in 1878. These skeletons were among the first complete dinosaurs ever found.

Although coal is much maligned because of its byproducts from combustion, the factors responsible for coal accumulation also give us fossil treasures from the past. To stop coal mining would undoubtedly mean many good fossils remain in the ground. But the long-term health of our planet is a bigger priority.

This is the first article in our series on the past, present and future of coal. Look out for others in the coming days.

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John will be online for an Author Q&A between 2:30 and 3:30pm AEST today (Wednesday 8 June, 2016). Post any questions you have in the comments below.

John Long, Strategic Professor in Palaeontology, Flinders University

This article was originally published on The Conversation. Read the original article.

Sandvik has created a new design for top centre drill bits.

According to the company they feature the largest upgrade to face drilling bits in decades.

Following field testing of the new bits, Sandvik recorded up to 80 per cent longer grinding intervals and up to 60 per cent long bit lives, which results in higher productivity due to longer service life, and a safer working environment due to fewer bit changes.

“The top priority when developing the new top centre rill bit was to increase service life,” Sandvik stated,” since the main reason for discarding a drill bit is excessive wear on the diameter, the simplest way to achieve longer service life is to add more gauge buttons.”

“However, this can prove problematic because of the minimal space available; furthermore an increase in the number or size of the carbide buttons generally decreases the penetration rate: the same impact force yields a lower net for per button.”

Sandvik believes it has now solved this problem with a ‘raised font’ elevating two or three front buttons – depending on the diameter size – by a few millimetres above the gauge buttons located on the periphery of the bit.

These front buttons are set at a slight angle relative to the symmetric axis of the bit, the raised front also creates a recessed hole bottom pattern that alters the rock breaking action to achieve improved performance.

In addition, the top centre bit also features a new cemented carbide grade, the GC80.

“The problem with carbides that exist on the market today is that they are either wear-resistant or tough,” Sandvik Mining top hammer tools product manager Robert Grandin said.

“When developing the GC80, we wanted to combine the best of those two worlds in order to get as much as possible out of the top centre design.

“The new bit design essentially delivers more drill metres per shift compared with a standard bit, thanks to fewer bit changes.”

The top centre drill bits are available in bit sizes 43, 45, 48 millimetres, with 2-3 raised end buttons and 7-8 gauge buttons in grade GC80 and connections R32, Sandvik Alpha 330, and R35.

Australia’s largest wire rope supplier WRI industries has been playing an ever-growing game since the 1920s, building a business from the BHP empire to become the largest supplier in the country, and thanks to a fortuitous buyout, the world.

Australia’s manufacturing industry cops a lot of bad press, and in focussing on stories about companies going bust due to managerial stagnation and waste, we forget about the success stories, the companies holding their own and continuing to press forward in productivity and innovation.

With the fall of Arrium last month, the mining industry would do well to acknowledge a business that arose from the BHP and the OneSteel empire, which will continue to thrive thanks to good management and sound investment: WRI Australia.

WRI Australia is the most successful wire rope business in the nation’s history. Dating back to its first rope produced for the mining industry in 1926, WRI has gone from strength to strength, streamlining operations to maximise efficiency over the past 90 years.

Until 12 months ago, WRI (Wire Rope Industries) was owned by the Arrium Group. The recent purchase by one of the world’s largest producers of wire and other related products, Belgian company Bekaert, may have saved the jobs of 100 Newcastle employees at the WRI factory.

At present, the chief claim to fame of the WRI business in Newcastle is the fact that it produces around 90 per cent of the wire rope used in the Australian mining industry. That’s ropes for draglines and shovels, ropes for cable-hauled conveyors, crane ropes and lifting gear, not to mention the structural ropes produced for engineering projects in other sectors.

A world-leader in the manufacture of drags, hoist ropes and pendants for draglines, as well as the shorter pendants for shovels, WRI’s is a story of successful management, of changing with the times in order to meet the needs of industry.

In its heyday as the Australian Wire Rope Works, a fully-owned subsidiary of BHP from 1933 onwards, the Newcastle factory produced many different wire rope products, and employed up to 450 workers at any one time.

Today the Newcastle factory, still with original art deco brick frontage, produces only 30 different products for the mining industry, and employs 100 people. Good management and top-class approach to safety made the company an attractive buy for a multi-national looking to take over the world’s wire rope business.

Baekart has all but monopolised the world’s manufacture of this important consumable, as late last year the Belgian manufacturer announced plans to merge with the largest wire rope manufacturer in the US, Bridon, to form a joint venture which will be named the Bridon Bekaert Ropes Group.

Meeting Australian needs.

With original BHP pedigree, WRI is primarily about mining supply, specialising in new-technology ropes that will last longer in the field.

Chief among the products manufactured in Newcastle are the plastic infused wire ropes, which were designed specifically for the mining market, to suffer the extremes of heavy use.

One of the key advantages of plastic infused rope is that it is impossible for dirt and rock chips to become embedded between the rope wires, where the intrusion can cause excessive wear and weaknesses in rope strands. The plastic coating serves as a barrier against contaminants and foreign bodies, which is especially important for shovel hoist ropes, which are exposed to contaminants in operation.

The other major benefit is that the impregnated plastic prevents the kind of wear that occurs within dynamic ropes, which are designed to be repeatedly put under load and strain, creating movement and wear between the wires. The impregnated plastic helps to retain the natural balance of the rope by locking strands in place to minimise the movement of component strands and wires during operation.

In addition, the plastic coating provides a smooth surface to pass over sheaves and drums, preventing nicking as well as wear to the sheaves, where a great deal of the outer wear on the rope occurs.

Each of these benefits adds up to a doubling of the expected operational life of each rope, which represents a significant saving when a single shovel pendant sells for around $20,000.

WRI also ensures additional levels of safety are built into the pendant sockets in a technique that ensures failure of the connection is impossible. By passing the rope into the socket, splaying out individual wires and filling the void with molten zinc, the safe working load of the connection is ensured to be greater than that of the rope.

WRI also specialises in long distance cable-haul conveyors, where resistance to corrosion is important to keep maintenance costs down, as is the number of splices in the rope made to achieve long distances.

According to WRI general manager Stuart Callender, Australia is home to one of the largest populations of overland conveyor systems, for materials handling from mines and loading facilities to ports.

“They take long continuous lengths of rope, so we took the opportunity to invest in machinery capable of achieving that. Those ropes are just under 10km long, and we make them in parcels of around 120 to 130 tonne.

Manufacturing the ropes in such long single lengths precludes the need to splice smaller ropes together, which would create unnecessary points of weakness in the rope.

With export markets in China, South America and South Africa to name a few, around 10-15 per cent of the total production from WRI in Newcastle goes overseas.

The success of WRI as Australia’s premier wire rope business is grounded in manufacturing experience dating from the 1920s, evolution and continual development of manufacturing techniques, and ongoing investment in technology, as well as service to the customer.