Beneath the cradle: a palace of coal
The remote region of Ordos in China possesses hydrocarbon wealth in the hundreds of millions of tonnes. Hard rock is leading customers to replace drill and blast with roadheaders and bolter miners.
Ordos lies in the heartland of China’s coal country. Nestled in a loop of the Yellow River, this Inner Mongolian administrative region – roughly the size of Ireland – possesses proven coal reserves of almost 150 billion tonnes. This amounts to around one-sixth of China’s total reserves. In terms of GDP –10,400 US dollars per capita – Ordos is one of the country’s wealthiest regions. It has boomed as coal fuels China’s spectacular economic development.
It is late afternoon at Wanli No. 1, a spacious mining complex amidst hills a 15-minute drive from Ordos City. A production manager watches a shift of coal-dust-covered workers disembarking from jeeps to the shower rooms and says, “One day all this mining will be automated.”
It’s a huge statement coming from a man working at the forefront of the industry. His employer, the Shenhua Group, is the largest coal-producing company in the world. Besides Wanli No. 1, Shenhua owns more than 60 other mines. In 2012, the state-owned energy company had power plants with capacity of more than 63 million kilowatts, 1,466 kilometres of railways, a shipping company with 11 ships, port capacity of 145 million tonnes and 211,500 employees.
Wanli Coal Mine
Two longwall faces of 5 kilometres
Armored face conveyor to belt conveyor
Number of employees: 1,200
Established in 1993
Already recognized as a global player in energy and mining, Shenhua aspires to be the most technologically advanced and productive coal enterprise in the world. According to Mining Weekly, the company currently boasts the lowest production cost for coal in China at about 250 yuan (29 euros) per tonne, while around 10 percent of China’s thermal coal producers have a break-even cost of around 500 yuan.
The Shenhua Group is leading China in the purchase of bolter miners, and Sandvik Mining currently has 100 percent of the market for this class of equipment. The process of the Sandvik bolter miner can be divided into two parts: cutting and bolting. These two can be performed simultaneously.
Wanli’s geological conditions are challenging. The roadways pass through hard rock from 0.5 to 1.8 metres in thickness. To cope, Shenhua acquired Sandvik MB670 bolter miner that can cut up to 50 metres of new roadway per day. The company has purchased the majority of the 80 MB670 units currently in use in China. Four are excavating the face gate road in Wanli No. 1.
Sandvik MB670 became the mainstay of Wanli No. 1’s roadway expansion because it makes forward progress at roughly twice the speed of any locally produced machine. Moreover, it can cope with rock hardness of up to 50 megapascals, which competitors hardly manage. Sandvik MB670 reduces the need to interrupt production schedules with drilling and blasting. The transition to bolter miners and roadheaders to replace blast mining is still ongoing throughout China.
Weighing 97 tonnes, Sandvik MB670 is a widehead bolter miner designed to cut and load coal while simultaneously bolting both roof and rib. The machine has four roof bolters and two rib bolters, permitting the operators to reinforce the roadway close to the face. There is enough breadth and height for a bus to drive.
Wanli No. 1 presently operatesSandvik MB670at depths of 150 to 200 metres, creating long walls for exploitation. Sandvik MB670 units will last seven or eight years, and with total overhaul the product life can be extended by up to an additional five years, depending on the application.
The Shenhua Group
• Listed on the Hong Kong Stock Exchange in 2005
• Has the largest coal reserves in China and is the largest supplier of coal in the country
• Fifth-largest electricity generator in China
• In 2012, the company reported a profit of 25.6 billion yuan, of which coal accounted for profits of 13.12 billion yuan.
• Shenhua is the sole coal-to-fuel producer in China and plans to quadruple output to 3 million tonnes annually by 2015.
• By 2015 the company plans to produce 5 million tonnes of chemicals and 1.2 billion cubic metres of natural gas from coal.
Shan Yongquan, mine production chief manager, Wanli No.1 Mine, Shenhua Group, is positive about Sandvik MB670’s introduction at the mine, terming it “modern, efficient and reliable” and praising the mine’s good relationship with Sandvik.
“Sandvik bolter miners are reliable and efficient,” he says. “The investment is fully justified. We have gone through the learning curve and there are many technical issues that we can now handle on our own, but we know Sandvik service engineers will come when we need them.”
Yan Hongqi, team leader for roadway development, Wanli No.1 Mine, Shenhua Group, is a 28-year veteran of the mining industry. He has been a key person in using bolters in the excavation of roadways.
“When we first got the bolter miners, we covered around 400 metres each month,” he says. “Last year we were averaging about 750 metres per month. In July, we reached over 1,000 metres – not a bad result.”
China’s coal mining industry is focusing heavily on improving its safety record. The last report from the State Administration on Worker Safety (SAWS) announced in 2013 that, in order to ensure work safety, it would no longer license mines that do not meet minimum production capacity requirements. According to the Xinhua news agency, the authorities plan to close 5,000 small coal mines, and SAWS is considering a rule to raise the annual production minimum for licensed mines in major coal-producing regions to three million tonnes.
“It is my job to see that the new young miners are properly mentored by the more experienced fellows so that they operate the equipment safely and correctly,” Yan says. In China, whose urban population now exceeds 700 million, Yan sees the temptation to cut corners.
“Yes, China needs more coal, and my job is to assure management that we increase production without compromising our safety standards,” he says. “We must keep our mine one of the safest in the world.”
Since the introduction of Sandvik MB670 in 2009, Wanli No. 1 has not suffered a single serious accident. Annual production is now around 10 million tonnes of coal, with capacity to produce an additional 3 million tonnes. Roadway excavation has been around 30 kilometres per year. Beyond the proven reserves there is even more coal. The seams run down to at least 1,500 metres. The mine’s geologically mapped reserves should last a minimum of 65 years.
Shan estimates that Wanli No. 1 can improve its economic efficiency by 10 to 15 percent with its current technology and infrastructure. The mine’s progress is being closely followed by other Shenhua subsidiaries, domestic mining companies and foreign mining concerns.
The pace of change in China’s coal mining industry has raised the bar for everyone. Shan is looking forward to the next generation of bolter miners. What does he want?
“We look forward to an even higher level of automation and safety,” he replies.
Peter Goel, product support manager, mechanical cutting, drill and bolt, feeder breaker at Sandvik Mining in China, believes the ongoing improvements in China’s coal industry are promising.
“China’s policies to consolidate and strengthen the large state-owned enterprises should improve the market for high-quality bolter miners and roadheaders,” he says.
“When I came to China three years ago, I set myself a goal of 100 machines,” he says. “Some people said that would take decades, but our customers are changing their mines. Sometimes the old infrastructure cannot keep up with machines, and there is a clear drive for improved profitability. Five years ago there was no dust collection system. Now with Sandvik MB670, it is standard. Our customers expect it.”
Sandvik MB670 Bolter Miner
It is designed to cut rectangular-shaped roadways while simultaneously installing rib and roof bolts. Sandvik MB670 can advance at up to 50 metres per day.
The Sandvik bolter miner features a temporary hydraulic roof support, rib protection and bolter operator canopy. The temporary support is located behind the cutting drum to ensure operator safety and stability of the equipment. The operation panel is equipped with a PLC control system and operates through remote controllers, realizing automatic control of horizontal position and roadway cutting height, as well as fully automatic control of the undercutting and cutting process. The cutter drum is designed for low-speed cutting and is equipped with the high-pressure water spray system and wet dust scrubber system, effectively suppressing the dust and diluting methane gas.
– Simultaneous cutting and bolting
– Support canopy behind the cutter drum, ergonomic operator platforms
– Low pick tip speed to reduce dust generation
– Sump in the slide frame – no crawler movement or floor destruction
– Capacity for four roof bolters and two rib bolters
– PLC control interlocks all machine functions, including sump and shear control
– Electronic level and cutting height control, machine health monitoring
– Fully radio remote-controlled, with display; in outburst conditions it can be operated with the aid of video monitors from a safe position
– 97-tonne machine, 2.7 metres in height, 11 metres long and drawing 546 kW of power
– Equipped with methane detectors