How long does it take to dig a 6000-meter roadway on a face with an annual coal output of more than 10 million tons? The answer is 4 months. The Caojiatan Coal Mine of Shaanxi Coal Group, located in the hinterland of the Maowusu Desert, can dig 55 to 65 meters of roadways a day with the help of advanced intelligent tunneling equipment, which effectively guarantees the development of coal mining. A few days ago, the reporter came to the production line of Caojiatan Coal Mine to find out. At about 10:00 in the morning, put on orange overalls, the reporter took a special explosion-proof vehicle into the underground mining area, about half an hour later, arrived at the working face 300 meters deep underground. I saw in the coal roadway, a 100-meter-long tunneling equipment was rotating the drum to break the coal seam, driving forward while supporting the roadway. "This big guy is the world's first set of integrated intelligent and rapid drilling and anchoring equipment independently developed by my country. We are the first coal mine to adopt." Caojiatan coal mine excavation team leader Zhang Hu introduced to reporters.
Coal mining, first need to dig into the roadway. Coal mine transportation, ventilation, pedestrians, etc. have the necessary access, and then can be mined coal. What is the difference between this set of equipment? Zhang Hu strode up the steps and led the reporter to the drill anchor device. "As long as you press it, the anchor rod will automatically penetrate into the coal seam, and one can be hit in less than 3 minutes." He pointed to the operation button said. Bolts are driven to support the coal seam. The buried depth of coal roadway often reaches several hundred meters. Effective support is very important to ensure that the coal gangs on both sides and the rock strata above do not collapse during excavation. Picking up an anchor rod, Wang Ziyue, an engineer of China Coal Science and Industry Group (hereinafter referred to as "China Coal Science"), talked about the high efficiency of "one-click anchor rod": in traditional support operations, drill holes are first drilled with drill rods, after the drill rods are removed, the anchor rods are driven into the drill holes, and then the surrounding rock is reinforced and supported. Drill pipe, anchor rod take turns to battle, a time to 6 processes. The use of drilling and anchor integration automatic support method, drill pipe is the anchor, 6 processes into 1, innovative roadway support technology. Zhang Hu took over the conversation: "in the past, the support operation required the cooperation of two people, one shift of more than 10 people to go down the well, one person to drill the drill pipe, the other to drill the anchor rod, which took a long time, and the labor intensity of the operation was relatively high. Now the work efficiency is high, and the operation intensity is greatly reduced." Along the miner's lamp, the reporter saw that the anchor rods were neatly and evenly arranged on the coal gang, firmly supporting the open roadway 300 meters underground.
The drilling-anchor integrated intelligent rapid excavation technology equipment simplifies the support process and improves the support speed of the roadway. Jiang Pengfei, executive director of the technology and equipment research and development project and chief scientist of China Coal Department, said that traditional fully mechanized excavators can only dig about 200 meters a month, but now they can dig more than 1500 meters a month. Why is it important to speed up roadway excavation? "Because it can solve the problem of coal mining imbalance." Kang Hongpu, director of the China Coal Science and Technology Commission and academician of the Chinese Academy of Engineering, explained, "More than 90% of China's coal mines are underground mines, and underground mining must first excavate roadways. Today, the coal mining face is highly automated and intelligent, in contrast, roadway excavation has dragged its feet and become a bottleneck in the safe and sustainable development of the coal industry." "The underground geological conditions of Caojiatan Coal Mine are relatively simple. We hope to use 3 to 5 years to transform and improve the technical equipment, so that it can be applied to complex geological conditions, and solve the problem of roadway tunneling in more mining areas and on a larger scale." said Concomp.
Following Zhang Jinhu, chief scientist of China's coal department, the reporter came to Caojiatan's 10-meter super-high intelligent fully mechanized mining face. Looking up, the coal wall is higher than 3 floors. The machine roared, the shearer lifted two cutting rollers with a diameter of 4.8 meters to rotate, and the rolling "Wujin" poured down from the coal wall, and then was continuously sent to the ground coal bunker through scraper conveyors, belt conveyors and other sources.
Why should the coal face be raised to 10 meters? Zhang Jinhu told reporters that about 10 meters of extra-thick coal seam is an important resource for China's coal supply. In the past, coal mining could only reach more than 8 meters at a time. In order to mine the extra thick coal seam as much as possible, the coal man can only mine it by multiple layers or top coal caving. However, after one mining in this way, the remaining coal seam is difficult to mine and the mining cost is high. Mining with the top coal caving process also has the problem of top stones mixing in and affecting coal quality. "To improve the efficiency of coal mining, the need for greater mining height, more intelligent coal mining technology and equipment." Zhang Jinhu said.
In November 2023, in Caojiatan Coal Mine, the world's first 10-meter super-high mining intelligent fully mechanized working face and supporting equipment were successfully put into operation under heavy load, and the first coal was mined. China's coal mining at one time reached the 10-meter mark.
"With this' coal mining weapon', the annual coal output of our single working face can be increased from 13 million tons to more than 20 million tons, the production capacity can be increased by more than 50%, and the recovery rate of coal resources can be increased by more than 10%." Cao Jiatan Mining Co., Ltd. deputy general manager Han Cun said. However, digging a large space of 10 meters high 300 meters underground, the overlying strata and coal walls of the coal mining face are facing tremendous pressure. "If the mining height is increased by more than 8 meters, even if the mining height is increased by 10 centimeters, the difficulty of controlling the rock formation and coal wall will increase sharply." Zhang Jinhu said that no one at home and abroad has ever done a 10-meter super-high mining height. Researchers broke into the "no man's land" of coal mining equipment design and research and development, and made breakthroughs in coal mine support, coal mining, and transportation equipment. problem.
On the coal mining face, the reporter saw that more than 100 hydraulic supports firmly supported the roof of the working face, and the extended protective arms supported the coal wall in front. Each hydraulic support here weighs 120 tons and has a supporting capacity of about 2900 tons. From more than 8 meters to 10 meters, not only the support height of more than 1 meter has been improved, but also the basic materials, processing equipment, technical technology and cognitive concept of coal mining equipment have been promoted in an all-round way.