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Kui sügavale üldse on inimesed Maa sisse puurinud? - Forte

Kui sügavale üldse on inimesed Maa sisse puurinud? - Forte:

Kui sügavale üldse on inimesed Maa sisse puurinud?

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26. märts 2014 08:00

Puurimisega alustati 24. mail 1970. aastal Murmanski oblastis ehk siis Koola poolsaarelkümme kilomeetrit Zapoljarnõi linnast läänes, kindla plaaniga teha sügavaim inimese tekitatud auk Maa sisse.

Koola ülisügav puurauk on täna 12 262 meetrit sügav ja saavutati see sügavus alles aastaks 1989. Esmalt oli puuritud Uralmash-4E, seejärel Uralmash-15000 puuridega, ja saavutatud sügavik oli tõesti sügavaim inimese tekitatud auk meie planeedi koores. Loodetud eesmärk, puurida 15 kilomeetri sügavuseni, jäi siiski saavutamata, ning puurauk suleti rahapuudusel 2005. aastal, kõik tehnika viidi ära ja ta on jäänudki unustusse alates 2008. aastast.

Põhjus, miks enam sügavamale puurida ei saanud, oli see, et temperatuur 12-kilomeetrise maakoore all osutus eeldatust ligi kaks korda kõrgemaks (mitte +100, vaid +180 kraadi) ja puurid ei pidanud enam vastu. 15 kilomeetri sügavusel oleks temperatuur kerkinud +300 kraadini. Sellel sügavusel oldi juba kihtides, mis on 2,5 miljardit aastat vanad. Ühest küljest oli üllatuseks, et seitsme kilomeetri sügavusel ei olnudki üleminekut graniidilt basaldikihile, teiseks aga see, et välja tulnud muda "kees" vesinikust.

Sügavusse puurimine oli samasugune suurriikide võidujooks, nagu pürgimine kosmosesse, kuid USA sarnane projekt Mohole oli juba 1966. aastal katki jäetud, kui 3600 meetri sügavusel mere all suudeti vaid 183-meetrine auk teha.

Saksamaal Windischeschenbachis jõuti 1990-1994 puurimisega 9101 meetri sügavusele, aga juba seal oli temperatuur kerkinud +260 kraadini.

Koola augu mahajätmisele aitas kaasa ka see, et just 2008. aasta maikuus puuris Maersk Oil Katari al-Shaheeni naftaväljal puuraugu 12 289 meetrini, ületades senise rekordi. Kuid nüüd ei kulunud sellele enam 19 aastat, vaid ainult 36 päeva.

Venemaa võttis rekordi tagasi 28. jaanuaril 2011, küll Exxon Neftegas Ltd. jõududega, kui see firma saavutas Sahhalini saare rannikul naftaaugu puurimissügavuse 12 345 meetrit. 2013. aasta suvel jõuti aga teadaolevalt juba 12 700 meetrini.

Thinking Big

16 October 2007

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High efficiency, increased productivity and big profits – large-capacity mining machines offer all this and more. Paul French discovers why, in the mining industry, size really matters.

"It's like driving a house," says Francis Bartley, the man who designed Liebherr's T282B dump truck. He's not exaggerating. The T282B is the largest capacity mining dump truck in the world. It boasts a 3,650-horsepower engine that guzzles 50 gallons of diesel per hour, 13ft tyres and a body capable of carrying approximately 400t.

It's fair to say that, in terms of machinery, the mining industry is thinking big. Caterpillar's 797B is just as capable as the T282B of shifting around 400t, whilst Komatsu's 920E-29 can take well-over 300t. Order levels for these monster trucks are higher than they have been for 25 years.

The question is: in an age where mobile phones and computers are getting smaller by the day, why is mining machinery getting bigger?

How are manufacturers responding to miners' needs? And is the 500t payload truck just around the corner?

ECONOMIC PRESSURE

"We are continuously looking into the improvement of our equipment to make it more efficient for the customer," says Liebherr Mining's product marketing manager Dion Domaschenz. "This may be in the form of ground-breaking design concepts, integrating the latest in technology or by way of improved customer support in terms of spare parts supply or technical assistance in the maintenance aspects."

The driving force behind this constant straining for improvement in the performance of the machinery is economic. Earlier this year BHP Billiton, the world's biggest mining company, posted a record-busting before one-off items net profit of $13.68bn. The company's peers CVRD, Xstrata and Anglo American also revealed hefty profits.

"Big mining companies will be keeping the pressure on manufacturers to constantly eke more efficiency out of their machines."

Whilst many look to exploit the boom and expand or, in the case of base metal mining companies, try to complement the fall-off in supply from ageing operations, it is clear there is both the need for better and more efficient machinery and the money available to invest in it.

For the mining industry better often means bigger. Where once a 240t-capacity dump truck was sufficient, a capacity of 400t is now expected. Liebherr's production of the monster trucks has increased 10–15% every year for the last five years to cope with the burgeoning demand.

However, whilst reporting record-breaking profits, BHP also noted that costs such as labour, raw materials, fuel and energy had risen in the last year by 3.6%.

With an eye on their profit margins and the continued threat that the price of commodities like gold, copper and iron may fall, it's a fair bet that the big mining companies will be keeping the pressure on manufacturers to constantly eke more efficiency out of their machines.

"It is a mixture of many things," says Domaschenz. "You need to look at transport and logistics limitations, potential customer base, costs, availability of components and risk. Costs are unlikely to be linear as the size of the equipment and components increase."

ENVIRONMENTAL EFFECTS

The other great pressure fueling the drive for greater efficiency and productivity from mining machinery is the environment. Due to ecological concerns associated with mining such as pollutants from drilling and blasting as well as leakage of fuel, oil, and other lubricants into ground water, it is becoming increasingly difficult for companies to open up new mines, increase the capacity of existing ones or even extend their mining licences.

"It is becoming increasingly difficult for companies to open up new mines, increase the capacity of existing ones or even extend their mining licences."

Subsequently, companies are forced into continually mining the same areas, driving demand for greater capacity and larger machinery to maintain the profitability and productivity of the mines.

TECHNOLOGICAL RESPONSES

Manufacturers have responded to the clamour for greater efficiency by producing better equipment. Improved motor design, process sensor controls, online analysis, advanced communication technologies and instrumentation robotics are just some of the areas in which energy and production efficiencies have been increased.

Changes to the machine design process, including automating and integrating the manufacturing and assembling process, have increased the speed with which manufacturers can respond to the industry's demands.

MONSTER TRUCKS

To be financially successful, a mine needs to move a high volume of material at as low a cost as possible. The more it moves in one go, without affecting its costs per ton, the higher its profit margins will be. That's where the monster trucks come in.

In the early 1950s hauler trucks had an average capacity of 27–35t each. By the 1960s capacity had increased to 85–200t and by the mid-1980s 240t-capacity trucks were standard. However, by the time the new millennium came around, Caterpillar and Liebherr found a way of nearly doubling that capacity.

"Standing over 24ft tall, the 797B is powered by a 3,500hp engine, has a designed operating weight of 1,230,000lb and a capacity of 360t."

The 797B was first seen at the Caterpillar proving ground in Tucson, Arizona, in 1998. Three years later, it became commercially available and mines around the world got their first taste of big. Standing over 24ft tall, the 797B is powered by a 3,500hp engine, has a designed operating weight of 1,230,000lb and a capacity of 360t.

The Caterpillar 797B and the Liebherr T282B may be powered differently – Caterpillar has developed a mechanical-drive engine whilst Liebherr's truck uses diesel engines to power electric generators – but they are both music to the ears of mining companies as they allow them to shift more material more quickly and turn a bigger profit.

In addition, Liebherr's T282B is lighter and more fuel efficient than mechanical drive trucks, allowing users to cut cost per ton figures by using less fuel.

CONTINUOUS MINERS

Joy's continuous miner is the largest underground mining machine in the world, according to the makers of TV show World's Biggest Machines. Since its original release in 1948, the continuous miner has constantly evolved to meet the demands of the mining industry.

One of the latest versions, the 12HM31-B MkII high-voltage 3.3kV machine, was developed by Joy South Africa in response to the demand from local mining companies for a higher productivity despite the hard-cutting conditions of the region.

The machine features the AC variable-frequency traction drive system Optidrive and the online JNAII surface communications system. It also includes the WetHead system, which reduces respirable dust levels, improves visibility, has an improved bit life and consumes less water than standard dust sprays.

The biggest Joy continuous miner, the 12HM36, is 3.54m high, 14.1m long and weighs over 120t. It is used for potash, salt and gypsum mining, whereas the 12HM31 is used for coal mining.

"The more material that can be excavated and transported in one go, the higher the profit margins will be."

EXCAVATORS AND LOADERS

Increased productivity gained by economies of scale is what is driving this evolution. In August Russian giant Mechel splashed out £3m on a pair of new backhoe excavators. The Liebherr and Komatsu machines would allow the company to increase annual ore excavation by 30%.

It is little wonder, then, that manufacturers are falling over themselves to go large.

At Bauma 2007 Liebherr premiered a new excavator, the R9250, which has 15% more bucket capacity and 42% greater swing torque than its predecessor, giving it much greater overall productivity. In April Caterpillar unveiled the 993K; a 25t-capacity, 1,050hp wheel loader in a size class of its own. Komatsu this year launched a pair of wheel loaders which it says are "more powerful, more stable and more environmentally friendly than their predecessors."

FUTURE PLANS

Bigger often means better in the mining industry because the more material that can be excavated and transported in one go, the higher the profit margins will be. But size isn't everything. Witness Caterpillar's new motorgraders, with joysticks replacing up to 15 levers, for an example of how cuteness can also lead to higher productivity.

"When it comes to large equipment there are challenges which exist in terms of component suppliers and transport and logistics."

However, a trawl through the product catalogues of vehicle manufacturers shows that many of the new and forthcoming trucks, loaders and excavators will be bigger, more powerful and more efficient than their predecessors. So should we be expecting a 500t payload truck in the near future? Not in the next few years, according to Liebherr's Dion Domaschenz. In fact, he says, bigger won't necessarily mean better as the industry progresses.

"There is pressure of course to push the limits of technology but when it comes to large equipment there are challenges which exist in terms of component suppliers and transport and logistics," says Domaschenz.

"There are many mines around the world which are currently not using the largest equipment currently available today and to go a step bigger than what is currently out there now effectively means that your potential customer base for the new product gets smaller as not everyone can use the equipment.

"With large trucks, you need large tyres and large engines, so there is a huge development cost with a small potential market right now. The payback time for this development will of course be longer, increasing the risk. We at Liebherr believe there is still some improvement in current equipment design that can be made to make it more efficient, instead of only focusing entirely on the idea that 'bigger is better'."

Liebherr's T282B is the largest-capacity dump truck in the world, capable of carrying 400t of material.

Continuous miners such as Joy's 12HM36 offer high levels of productivity, even in areas less conducive to mining.

The Caterpillar 797B has a 3,500hp mechanical-drive engine that improves efficiency for mining companies.

The world's worst mining disasters - Mining Technology

The world's worst mining disasters - Mining Technology:

The world's worst mining disasters

10 September 2012 Sarah Blackman

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Explosions, strikes and collapses have caused some of the worst mining tragedies in recent years. From Pike River to Marikana, mining-technology.com lists the deadliest mining events of the decade.

The San Jose mine in Copiapo, Chile, is best known for the 2010 collapse which left 33 miners trapped

In the wake of two huge mining disasters, plans put forward by China to eliminate outdated production methods, shutdown illegal collieries and improve facilities at viable mines have never been more pressing.

"Thousands of miners die in accidents on site every year, especially in the process of coal and hard rock mining."

The government announced in May 2012 that it will shut down 625 coal mines with a total production capacity of 23.47 million tons by the end of the year, a move that could finally put an end to dangerous and exploitative conditions faced by miners in the country.

But the news comes too late for the victims of the Xiaojiawan mine disaster. On 29 August, a gas explosion at the facility, located in Sichuan province, killed 45 workers and injured 54 others.

Five days later, another 15 workers lost their lives in an explosion at the Gaokeng Coal Mine in Jiangxi province.

Thousands of miners die in accidents on site every year, especially in the process of coal and hard rock mining. Here, we list some of the biggest mining disasters of the last ten years.

Crandall Canyon, US

On 6 August 2007, the Crandall Canyon mine, an underground bituminous coal mine in Utah, collapsed. Six workers were killed in the accident and three rescuers lost their lives in a second cave-in just ten days later.

The shockwaves registered 3.9 to 4.0 by seismographic stations in Utah and Nevada, leading to an initial belief that the collapse had been caused by an earthquake.

Investigations later revealed, however, that the implosion was caused by shearing away at the huge coal columns that supported about 1,700 feet of mountain above.

Rescue operations were eventually called off and the bodies of the miners were never recovered.

Upper Big Branch, US

A coal dust explosion at Massey Energy's Upper Big Branch mine in West Virginia killed 29 out of 30 on-site miners on 5 April, 2010. The accident was the worst the US mining industry had seen since 1970, when 38 workers were killed at two mines in Kentucky.

A final report from the Mine Safety and Health Administration (MSHA) in December 2011 concluded that safety violations contributed to the explosion. Massey Energy had apparently failed to properly maintain its ventilation systems, which allowed methane levels to increase to dangerous levels.

The administration issued 369 citations, assessing $10.8m in criminal penalties.

San Jose Mine, Chile

The San Jose mine in Copiapo, Chile, is best known for the 2010 collapse which left 33 miners trapped 2,297 feet underground for 69 days.

On 22 August, 17 days after the collapse, the miners were found alive by rescuers who drilled down 2,257ft to make contact with the workers.

A note from the miners indicated they were living in a makeshift refuge. Using a bulldozer, they created a canal of fresh water and used electricity from a truck engine to rig up lighting deep inside the copper-gold mine.

The miners were hoisted to safety via a rescue capsule on 13 October 2010.

A Chilean congressional commission found owners Alejandro Bohn and Marcelo Kemeny responsible for the collapse. The mining company, San Esteban, is under bankruptcy protection and its assets have been sold off to help resolve debts and pay severance to the miners.

Pike River, New Zealand

A series of four explosions occurred at the Pike River mine, once the second largest hard coking coal export mine in New Zealand, between the 19 and 28 November 2010.

At the time of the first explosion, 31 miners and contractors were working on site. Two miners walked away from the incident and were treated with moderate injuries.

The remaining 16 miners and 13 contractors were believed to be at least 1,500 metres from the mine's entrance and after the second explosion on 24 November, the men were believed by police to be dead.

When rescuers drilled a borehole into the area where the miners were thought to be, a dangerous level of methane and carbon monoxide was detected, leaving the workers with little chance of survival.

In July 2011, the Australian newspaper ran an article that alleged that Pike River CEO Peter Whitthal had not ensured that the mine had installed appropriate safety measures.

Marikana Platinum Mine, South Africa

On 10 August, 2012, rock drill operators at the Marikana Platinum mine in the North West province of South Africa threw down their tools in protest about wages.

The strike spiralled into clashes between two rival unions - the National Union of Mineworkers (NUM) and the Association of Mineworkers and Construction Union - and led to the death of 35 workers and two police officers.

Four weeks later and only 4.2% of shift workers have returned to work and the value of Lonmin, the owner of the mine, has fallen by 30% in the past month.

Crandall Canyon, United States of America

The coal mine is located in the north-west of Emery County, 35 miles south-east of Fairview and 15 miles west north-west of Huntington, just off Utah State Route 31 and surrounded by the Manti-LaSal National Forest.

Pike River Mine, New Zealand

It is located about 50km north-east of Greymouth in the west coast region of South Island.

Marikana Platinum Mine, South Africa

The Marikana mine is located in the North West Province of South Africa, approximately 8km east of the Kroondal mine.

Summon for safety: Q&A with US mining policy-maker

How are governments laying down the law to ensure health and safety in the mining industry?

A strike at the Marikana Platinum mine led to 37 deaths.

The New Zealand flag flies at half mast to mark the official memorial service for the Pike River miners.

Rescue efforts in process at the San Jose mine.

Manuel González, the first rescuer, preparing to descend into the San José mine.

The top 10 gold producing countries - Mining Technology

The top 10 gold producing countries - Mining Technology:

The top 10 gold producing countries

7 October 2013

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The ten largest gold producing countries accounted for about 65% of global gold output in 2012. China and Ghana witnessed double digit growth in gold production, with a notable increase in gold output from Russia, Peru and Canada. Mining-Technology lists the largest gold producing countries based on 2012 gold production data.

China

China is the largest gold producing country in the world, producing 403t (tonnes) of gold in 2012, an 11.7% increase in production over the previous year.

The country accounted for 13.7% of the global gold production in 2012. China also tops the list in gold consumption.

The majority of the Chinese gold production comes from five provinces, namely Shandong, Henan, Jiangxi, Yunnan and Fujian. Zijin Mining Company, which operates Zijinshan gold and copper mine, is the country's largest gold producer.

Australia

Australia is the second main gold producing country in the world. It produced 253t of gold during 2011-12, a four percent decrease over 2010-11production. Australia contributed 9.31% of global gold output in 2012.

Most of the Australian gold mines are located in Western Australia, South Australia and New South Wales, with 71% of gold production coming from Western Australia alone. Australia's reserves of gold as of December 2012 were estimated at 7,400t (13.7% of the global total) by the US Geological Survey.

United States of America

The United States, which accounts for 3.5% of global gold reserves, is the third largest gold producing country in the world. It produced 230t of gold in 2012, a decline by 4t from 2011. The US accounted for 8.5% of global gold production in 2012.

The gold production comes predominantly from five states - Nevada, Alaska, California, Colorado and South Dakota. More than 74% of gold is mined from Nevada alone.

Carlin Trend gold mine, operated by Newmont in Nevada, is the US's largest gold mine, containing gold reserves of 17.83Moz.

Russia

Russia ranks as the fourth largest gold producing country. It produced 205t of gold in 2012, a 6.8% increase over 2011 production.

Russia contributed 7.6% of the global gold output in 2012.The country's gold reserves were estimated at around 5000t as of December 2012 by US Geological Survey.

Gold producing mines in Russia are mainly located in six eastern regions - Amur, Irkutsk, Khabarovsk, Krasnoyarsk, Magadan and Sakha-Yakutia.

Olympiada mine, operated by Polyus Gold, is the largest gold producer in the country, which produced 720Koz of gold in 2011.

South Africa

Historically the largest gold producing country, South Africa currently ranks as the fifth largest. The country's gold production in 2012 stood at 170t (6.3% of global production) compared to 190t in 2011.

The decline in gold production was due to numerous gold mine strikes during the same year.

South Africa has 35 large-scale gold mines currently in operation, including the world's deepest mines such as Tau Tona and Mponeng. The country's contained gold reserve as of December 2012 was estimated to be about 6,000t (11.5% of the global gold reserves).

Peru

Peru is currently the sixth largest gold producing country in the world. The country produced 165t of gold in 2012, a three percent decline over 2011 production. Peru accounted for 6.1% of global gold output in 2012.

Compania de Minas Buenaventura is the main gold-producing company in the country. Yanacocha mine is the largest gold mine in Peru. The country accounted for 4.2% of the global gold reserve as of December 2012.

Ghana

Ghana ranks as the seventh largest gold producing country in the world. The country produced 4.2Moz (119t) of gold in 2012, which was a 17% increase on 2011 production. The gold production accounts for more than 90% of the country's total mineral output.

Ghana is the second largest African gold producing country. The country's largest gold mine, Tarkwa is operated by Gold Fields. The US Geological Survey estimated the country's gold reserves as of December 2012 at 1,600t, which accounts for 3.1% of the global gold reserve.

Canada

Canada is the eighth largest gold producing country, with a gold output of 102t in 2012, five percent more than in 2011. The country's share in global gold output in 2012 was 3.8%.

The gold mines in the country are mostly located in Ontario. Goldcorp operates the Red Lake gold mine, which is the largest gold producing mine in the country. Canada held 1.8% of global gold reserve as of December 2012.

Indonesia

Indonesia ranks as the ninth largest gold producing country in the world. It produced 95t of gold in 2012, which comprises of 3.5% of the global production during the year. The country's gold production in 2011 was 96t. The decline in gold production was due to the illegal mining and political unrest in the country.

The world's biggest gold mine Grasberg, with an estimated gold reserve of 70.96Moz, resides in Indonesia. Freeport McMoran, Newcrest and Newmont are the major mining companies operating in the country. Indonesia contained 5.8% of the global gold reserves as of December 2012.

Uzbekistan

Uzbekistan is the tenth largest gold producing country, with a production of 90t of gold in 2012. Muruntau open pit mine, one of the largest gold mines in the world, contributes around 70% of the country's annual gold production.

The state-owned Navoi Mining and Metallurgical Combinat (NMMC) is the dominant gold producing company in the country. There are more than 40 gold deposits in Uzbekistan. Estimated gold reserves of the country stand at 1,700t.

Top 10 biggest gold mines

Indonesia is home to the world's biggest gold mine while South Africa, which houses the majority of the deepest mines in the world, also hosts two of the top 10 largest gold mines.