Original Title: New Progress in Key Technologies for Underground Metal Mining
Underground metal mine mining is a systematic project, including development,
development and mining (as shown in Figure 1, underground mine mining model),
each link requires blasting. Therefore, how to blast safely and efficiently is a
subject for every miner to study. Fig. 2 Underground mining mode At present,
metal mines are facing the key transition period of "from shallow to deep, from
easy to difficult, from rich to poor", and are facing new challenges in theory,
technology and equipment. In the face of the above challenges, the research on
the key technologies of underground mining in metal mines is particularly
critical. At present, the key technologies of underground mining in metal mines
are mainly embodied in the following five aspects: drilling and blasting
technology, transportation and lifting technology, rock reinforcement
technology, paste filling technology and remote control technology. Around these
five key technologies, this study systematically reviews their development
history and new progress, and the key technology architecture of underground
mining of metal mines is shown in Figure 2. Figure 2 Key technology architecture
of underground mining in metal mines 1. Rock drilling and blasting technology
Rock drilling and blasting technology is an important technology in the process
of metal mining, and it is also a weak link in the long-term development of
metal mining. Therefore, it is very important to continuously improve the
efficiency of drilling and blasting for the safe and efficient mining of metal
mines. At present, rock drilling and blasting technology is still the main means
of underground mining, from the initial manual rock drilling to pneumatic rock
drill, hydraulic rock drill, drilling jumbo (rotary drill, down-the-hole drill),
and even the present rock drilling robot, rock drilling technology has gradually
developed from mechanization to automation, intelligence and environmental
protection. Expand the full text After a long period of research, drilling
equipment suitable for various conditions has been developed at home and abroad.
In recent years, with the improvement of drilling equipment, the United States,
Canada and other countries have introduced open-pit drilling and blasting
technology in underground mining, and medium-length hole sublevel drilling has
been replaced by large-diameter stage deep hole, which has achieved good
application results. For example, Sweden has developed a series of tunneling
drilling jumbos, which have the advantages of high drilling efficiency, safe
operation and low pollution; China has independently developed a set of drilling
jumbos. The fully computerized three-arm rock drilling jumbo, which integrates
drilling and charging operations, has the advantages of simple operation, high
safety factor and low construction cost. These equipments ensure the quality and
efficiency of rock drilling, reduce labor intensity and operation risks, and
achieve a new level of automation, intelligence and environmental protection. At
the same time,Borehole
Drill Bits, due to the different conditions of underground mining and the
different application conditions of roadway excavation and mining operations,
the blasting methods commonly used in traditional underground mines are
diversified, such as millisecond blasting, extrusion blasting and smooth
blasting, which improve the blasting quality to a certain extent. With the
development of blasting technology, the traditional blasting technology is
gradually developing towards precision blasting, green blasting and intelligent
blasting. The mine precise blasting system is constructed mainly through the
fine design of hole pattern parameters, the theoretical study of blasting energy
consumption and the simulation of blasting scheme. The green blasting mainly
uses new incendiary agents instead of explosives. ? No blasting gas is
generated, which greatly improves the underground air environment and realizes
underground green blasting; intelligent blasting is mainly designed by blasting
intelligence. Intelligent equipment, intelligent prediction of blasting
vibration and automatic identification of residual holes constitute an
intelligent blasting system to realize the intellectualization of blasting
technology. In the new era of technological progress and innovation, rock
drilling and blasting technology has developed from traditional methods to
non-blasting rock technology such as mechanical and physical rock breaking. For
example, the continuous mining machine is used for mechanical rock breaking of
medium hard and below ore rock, which has high working efficiency and good
construction conditions and is beneficial to ground pressure control; The
physical rock breaking technology of thermal crushing overcomes the limitation
of rock breaking by mechanical energy alone, does not produce dust and sparks,
and greatly improves the working environment. However,down the
hole bit, due to the problems of high energy consumption, high cost and
serious wear and tear of props, it has not yet been popularized in China. At the
same time, at this stage, China started late in the research and development of
information technology and artificial intelligence technology, and the related
core technologies of intellectualization are still mainly dependent on foreign
countries. Therefore, at present, continuous mining has not been really realized
in hard rock mines in China. 2. Transportation and lifting technology
Transportation and lifting system plays an extremely important role in the
production of underground mines. Through transportation and lifting, all links
can be connected into an organic whole, so as to ensure the normal production of
mines. The stope ore removal has experienced the development process of "manual,
rail and trackless" transportation technology, and has formed a new situation
from rail as the main and trackless as the supplement to trackless as the main
and rail as the supplement. Trackless self-propelled equipment transportation in
underground mines began in the 1960s. With the improvement of underground
trackless equipment, underground trackless mining technology has developed
rapidly, which promotes the transformation of underground mining technology and
is the development trend of underground mining at present. Scraper is used for
short-distance ore removal in the stope, which has the advantages of convenient
operation, reliable work, high ore removal efficiency and flexible operation.
Underground truck is used for long-distance ore removal in the pit. At present,
it is widely used in foreign countries, but rarely used in China. With the
increase of mining depth, the lifting distance is increasing, and the lifting
technology is facing more and more challenges, accompanied by the increase of
lifting costs of various ore materials. Therefore, it is particularly important
to develop deep mine ore hoisting technology. On the whole, it is the future
general trend of mine transportation and lifting to develop in the direction of
large-scale, heavy load and high automation. After a long period of development,
in deep mining, the vast majority of mines use rail transport, belt conveyor or
trackless equipment to carry out multi-level shaft lifting. For example, in
TauTona Gold Mine in South Africa, dth
rock bit ,mining
drill bit, a three-stage shaft lifting method is used, and then the transfer
between shafts is carried out by belt or trackless equipment. Although the
traditional open belt conveyor system has a simple structure, it is easy to
cause dust and slide, pollute the underground environment, and has poor climbing
ability and low safety factor. SiCON has developed a closed belt conveyor system
to prevent sliding and dust during transportation. The transportation speed can
exceed 3 m/s and the lifting slope can reach 36 °. Appropriate improvement of
the system is expected to be applied to the ore transportation and lifting in
deep mining in the future. At present, hydraulic lifting is mainly used in
deep-sea mining. In recent years, some researchers have tried to apply hydraulic
lifting in deep mines. This process can be carried out continuously, which is
easier to realize the automation and intellectualization of the lifting process.
However, the use of hydraulic lifting requires the establishment of ore crushing
system and grinding system in deep mines, which is difficult to be applied in
practice at present. At the same time, there is also an innovative idea of
magnetic levitation elevator, but it still needs to be studied in depth and
meticulously. These new technologies, new methods and new processes have
injected fresh blood into the field of mine transportation and lifting, and
greatly promoted the innovation and innovation of transportation and lifting
technologies, methods and processes. 3. Strata reinforcement technology Metal
mines are mainly aimed at reinforcing weak, broken and highly stressed rock
strata. Rock reinforcement technology can be divided into passive support and
active support. Passive support can not change the internal structure of rock,
but can only passively bear the deformation of surrounding rock, such as
traditional wood support, masonry support and steel arch support. Active support
can change the internal structure of rock Actively strengthen the strength of
rock strata, such as bolt (anchor cable), bolt-grouting, bolt-shotcrete and
bolt-mesh-shotcrete and other support methods, in which bolt-grouting support,
bolt-shotcrete support and bolt-mesh-shotcrete support belong to composite
support. Bolt-shotcreting support has become the main reinforcement technology
of rock strata in metal mines. Full-length grouted anchor is composed of
full-length grouted bolt and grouted bolt, which greatly improves the anchoring
strength and has a good promotion value and application prospect in engineering
practice. Shotcrete has developed from dry shotcrete to wet shotcrete The
working environment is improved, and the spalling of the rock stratum is
prevented. The effective combination of shotcrete and bolt can control the free
deformation of surrounding rock within a certain range, redistribute the stress
of surrounding rock, and effectively prevent the stripping and falling of rock
strata. With the rapid development of science and technology, the use of
advanced equipment related to bolting and shotcrete support is increasing at
home and abroad. For example, foreign countries have developed a series of
equipment such as anchor trolley, wet spraying trolley and hanging net trolley.
At the same time, China has independently developed tire anchor trolley (crawler
anchor trolley), mining wet spraying machine and two-arm concrete wet spraying
machine, which not only improves work efficiency, but also reduces labor
intensity and ensures operation safety. To a certain extent, the mechanization
and intellectualization of rock reinforcement technology have been realized.
After several technical innovations, the rock reinforcement technology has
developed from the traditional passive single support to the new active
composite support, and will show the development trend of mechanization and
intellectualization in the future, in order to improve the safety and operation
efficiency. 4. Paste filling technology Solid waste pollution, water pollution,
air pollution and land occupation caused by metal mining are very serious. With
the development of filling mining technology and equipment, paste filling
technology provides a new idea to solve the problems of traditional mining and
environmental pollution caused by metal mining. The whole tailings and other
solid wastes are prepared into saturated, non-bleeding, toothpaste-like
structural flow slurry for paste filling, which can solve the two major hidden
dangers of tailings reservoir and goaf. So as to ensure the sustainable
development of the mine. Compared with the traditional water-sand filling, paste
filling has the characteristics of "three noes", namely, no stratification, no
segregation and no dehydration of slurry. At present, China has built the
world's first industrial paste filling test platform, covering an area of about
2 000 m ², with more than 200 sets of equipment, which has the characteristics
of high industrial precision, full function and intelligence, and can carry out
experiments, parameter detection and guide system design and engineering
practice for the whole process of paste filling technology, especially for
multi-pipe diameter, multi-direction and multi-flow. Compared with the
traditional method, the detection result is closer to the reality. The common
basic theory of each process of metal ore paste filling is metal ore paste
rheology, which takes paste rheological constitutive equation as the research
content, and takes theoretical calculation, rheological experiment and numerical
simulation as the main research means to meet the engineering requirements of
four process links in paste filling, namely, tailings thickening, paste
stirring, paste transportation and filling solidification. Thickening technology
aims to obtain a stable and appropriate underflow concentration, which lays the
foundation for the preparation of qualified paste; stirring technology makes the
materials mixed evenly ? Provide conditions for fluidization and mechanical
property homogenization of paste pipeline transportation; transportation
technology pursues low energy consumption And that fil technology realizes the
uniform distribution of the strength of the fil body and the full top contact
rate. The above four processes correspond to the four key technologies of paste
filling. Paste filling technology has the rich connotation of "safety, economy,
environmental protection and high efficiency", which is an important technical
support for the green mining system of metal mines, and has been listed as a
demonstration technology by the relevant ministries and commissions of China,
and is a research hotspot in the field of global mining. The core theoretical
architecture of paste filling is shown in Figure 3. Figure 3 Figure 3 Paste
filling core theory system architecture 5. Remote control technology With the
development of science and technology, mining technology is also progressing,
from the initial manual mining to mechanized mining, and then to the present
automatic mining, intelligent mining, whether automatic mining or intelligent
mining, remote control is the core technology. Therefore, remote control
technology will play an irreplaceable role in modern mining, and it is an
important technical means for the development of modern mining. Remote control
technology is a relatively mature control technology in the world, and it is
also a direction of underground mine development, including drilling remote
control, charging remote control, ore drawing remote control and so on. However,
this technology is a supporting application technology after the overall
development of a country's industry to a certain height, and has not yet been
fully promoted in China. The key technologies of remote control are mainly
embodied in three aspects: remote sensing of mining environment, remote
operation of mining process and remote management and control of mining system,
so as to realize the functions of automatic sensing and analysis, unmanned
operation, remote allocation,mining dth
bit, automatic early warning and remote decision-making. Break through the
key technology of intelligent mining of underground metal mines, improve the
market competitiveness of mining enterprises and mining equipment manufacturing
enterprises in China, and provide technical support for China to move from a big
mining country to a powerful mining country. Return to Sohu to see more
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