Metal Mine

New Development and Prospect of Key Technology in Underground Mining of Metal Mines

WU Aixiang, WANG Yong, ZHANG Minzhe, YANG Gangfeng

2021, 50(01): 1-13.

Asbtract ( 2532 )

PDF (3623KB) ( 2308 )

Related Articles | Metrics

Mining is an important pillar industry for the stable development of China's national economy and national security. It provides a steady flow of raw and auxiliary materials for many industries and agricultures. It is an irreplaceable basic industry in the modern economic system. With rapid development of the national economy，the contradiction between supply and demand of China's metal mineral resources becomes more and more prominent. Although China's output of crude steel，ten kinds of non-ferrous metals and gold has ranked first in the world for many years，iron，copper and other bulk mineral raw materials are heavily dependent on imports. While surface resources keeps depleting，underground mines will be the main battlefield of metal mining. In view of the current research status of underground mining of metal mines，"deep mining"，"intelligent mining" and "green mining" will be the three development directions of metal mining in China. Rock drilling and blasting，transportation and lifting，rock reinforcement，paste filling and remote control are currently the five key technologies for underground mining of metal mines. Around these five key technologies，the development process and new progress are systematically reviewed. Finally，the prospective technologies and theories of underground mining of metal mines such as robotic mining technology，fluidized mining technology and super-large smart mine construction are put forward. The new situation brings new opportunities to the development of mining industries that are facing the key transition period "from shallow to deep，from easy to difficult，and from rich to poor" mining，and new challenges in theory，technology， equipment and other aspects. The opportunities and challenges have urged us to explore and innovate to tackle key scientific and technological problems，to break through key technical bottlenecks，and to develop core equipment independently. This will lead to safe，economical，efficient，environmentally friendly and intelligent mining of mineral resources，and guarantee the safety of China's metal mineral resources.

Summary of Research Progress on Floc Structure of Tailings Thickening for Paste Backfill

LI Cuiping, CHEN Gezhong, HOU Hezi, YAN Bingheng

2021, 50(01): 14-23.

Asbtract ( 1010 )

PDF (1356KB) ( 1002 )

Related Articles | Metrics

One of the technical problems of paste backfill is how to prepare a stable and suitable underflow in the pro‐cess of tailings thickening，so as to meet the needs of subsequent process links and provide technical support for safe and ef‐ficient production in mines.However，in actual engineering，the underflow concentration of the tailings thickening is often un‐stable. Based on the latest research progress in the field of tailings thickening，it is found that the underflow concentration is affected by the macroscopic factors of the thickening process，and the root cause depends on the microscopic view of the floc structure during the thick dehydration process. Therefore，by reviewing domestic and foreign research progress of tailings thickening in tailings flocculation，tailings floc structure change，floc water content change，bed pore channel development and evolution，and compaction zone dewatering，systematic analysis of the mechanism of the external conditions on the change of the floc structure in the dense，the cause of the change of the floc water content by the structure of the floc，the influence of the floc water and the pore channels in the compaction zone on the underflow concentration，it is concluded that the flocculation conditions determine the initial form of the floc structure，the fluid shear force in the settlement zone，the pressure of the tailings bed in the compaction zone and the shearing effect of the rake change the structure of floc，the water content of the floc will change with the change of floc structure，it changes and is discharged through the pore channels of the bed to increase the underflow concentration of the thickener. Furthermore，based on the research progress at home and abroad，the microscopic effect of the change of floc structure on the thick dewatering of tailings is deeply discussed，and the current problems and future development trends of tailings thickening of dewatering are put forward.

Flotation Chemistry of Tungsten Ore and Its Practice

SUN Wei, WEI Zhao, HAN Haisheng, GAO Zhiyong, WANG Jianjun, WANG Ruolin

2021, 50(01): 24-41.

Asbtract ( 600 )

PDF (3476KB) ( 860 )

Related Articles | Metrics

Tungsten is an important strategic metal，which is of great significance to the national defense security，national resources security andthe development of strategic emerging industries.The development of tungsten flotation chemistry has solved a series of key bottleneck problems of complex tungsten flotation and provides the important supports forthe efficient and clean development and utilization of the complex scheelite and the scheelite and wolframite associated resources in China.The advance of tungsten mineral flotation reagents and technologies were reviewed. And the relationship among mineralogy，crystal chemistry，solution chemistry，and flotation was developed. During the geological mineralization，fluorite and calcite are usually associate with tungsten minerals，leading to the difficulties the flotation separation of calcium minerals.The subtle difference in crystal structure and interfacial properties provide the feasibility for the flotation separation. Modified fatty acid，cationic collector，chelate collector，metal complex collector，and the assembly of surfactants realized the flotation separation between tungsten minerals and calcium minerals. A simplified flotation process using Pb-BHA complexes was developed to replace the energy-inefficient Petrov's process of using a fatty acid，increasing the recovery of scheelite and reducing the cost. In summary，the geological mineralization mechanism，crystal chemistry and solution chemistry oftungsten ore determine the difficulty of tungsten ore flotation separation and guide the development of tungsten ore flotation reagents and new technology，which provides a solid support for cleaner development of complex tungsten resources.

Current Status in Study of Genetic Flotation of Minerals

YIN Wanzhong, TANG Yuan

2021, 50(01): 42-54.

Asbtract ( 369 )

PDF (2347KB) ( 859 )

Related Articles | Metrics

The inefficient R&D mode of mineral flotation with the long period and high cost is due to the absence of systematic research and summary of the“Genetic Properties”of deposits，ores，and minerals. The concept of“Genetic Flotation” is helpful to optimize the research of mineral flotation technology and lay a foundation for the further development of “Genetic Mineral Processing Engineering（GMPE）theory”. The influence of physics and chemical items of typical deposits， ore structures，and crystal structures on mineral flotation were preliminarily explored，and the development and prospect of data mining and modeling in mineral flotation were introduced. It is clarified that the industrial application of flotation based on big data is the technical goal. Through the analysis of the relationship between the genetic properties of deposits， ores，mineral and mineral flotation，it is pointed out that the genetic types of deposits，ore structures，and crystal chemical properties of minerals directly affect the flotation behavior and separation characteristics of minerals. The scientific research data of minerals flotation are collected，processed，and analyzed using modern information technology，which helps to achieve breakthrough development in the field of flotation. Finally，the applying prospect and suggestions of“Genetic Flotation”were given. The systematic studies of“Genetic Flotation”of minerals would help to provide the basis and data support to the rapid and accurate formulation of flotation separation technology and process of different ores. They would also make an innovative breakthrough in flotation test and engineering methodology，enriching the theory of GMPE.

Research Progress on the Preparation and Application of Semiconductor Gas Sensors Used for Mining Safety

SHEN Yanbai, LI Guodong, HAO Fulai, ZHOU Pengfei, ZHAO Sikai

2021, 50(01): 55-70.

Asbtract ( 226 )

PDF (4786KB) ( 734 )

Related Articles | Metrics

Toxic and harmful gases in the mining industry such as CH4，H2S，NOx，SO2，CO，and H2 are one of the main reasons causing mining safety accidents. These gases may directly endanger the health of employees and the safety of the company property. Therefore，it is of great significance to realize early perception and active warning for these gases in mining safety. Gas sensor is a device that can detect the type and concentration of the target gas and output it as an electrical signal. Among different types of gas sensors，the semiconductor gas sensors have many advantages such as fast response， high sensitivity，stable performance，simple structure，and low cost，which makes them receive extensive attention in the research field of gas sensing and account for the largest proportion in practical applications. Semiconductor gas sensors have been successfully applied to the detection of mine gas，and recently they have also been used to monitor other toxic and harmful gases in mining. This paper reports the working principle，structure，and main performance parameters of the semiconductor gas sensors used for mining safety.The main preparation processessuch as template method，hydrothermal method，solvothermal method，gas phase reaction method，solid state reaction method，sol- gel method，electrospinning method，microwave-assisted method are provided，and research progress of the semiconductor gas sensing materials is given. Three main ways to improve the gas sensing performance of semiconductor materials are analyzed，namely microstructure control，noble metal doping，and construction of heterojunctions.In addition，the research status of toxic and harmful gassensors in the mining industry is described. The room-temperature response，high performance，wearable gas sensors are the research focuses on mining-safety gas sensors in the future.The research and promotion of high-performance semiconductor gas sensors are of great significance to the detection of toxic and harmful gases generated and discharged during the exploration and development of mineral resources，to improve the safe production of mines，and to realize the healthy development of mining resources in China.

Research Progress on Several Problems of Expansive Materials for Expansive Slurry

YE Yicheng, CHEN Changzhao, YAO Nan, WANG Qihu, CUI Xuyang, HUANG Zhaoyun

2021, 50(01): 71-93.

Asbtract ( 268 )

PDF (4748KB) ( 957 )

Related Articles | Metrics

The steeply inclined layered rock masses of the roadway roof is prone to "slip along the bedding" break along the weak bedding surfaces. The expansive slurry is used to slurry the weak bedding surfaces to produce the "first squeezing and then bonding" reinforcement effect，which could improve the strength and integrity of the roof surrounding rock. Aiming at the expansion grouting reinforcement and support technology，the concept of expansive slurry was proposed， and the expansion mechanism of expansive slurry was analyzed. The selection of expansive materials for the expansive slurry is the key issue.By summarizing the development history of various expansive materials and the research status at home and abroad，the expansion mechanism of them were discussed. The properties of expansive materials were analyzed from four aspects such as expansion development time，volume expansion rate，mechanical strength，and expansion stress. On the basis of these，HSCA- Ⅱ static cracking agent was selected as the expansion source. The expansion development time，volume expansion rate and mechanical strength characteristics of the static cracking agent-cement expansive slurry were analyzed through the tests including the expansive slurry ratio test and volume expansion rate test，mechanical strength test. Research results show that with the increase of the content of static cracking agent，the compressive strength of the static cracking agent-cement expansive slurry decreases，the expansion development time is prolonged，and the volume expansion rate increases. The static cracking agent-cement expansive slurry has reasonable expansion development time，large volume expansion rate，high self-strength，and the expansion stress can provide squeezing force in supporting rock mass，which may have good engineering application significance. In order to achieve good engineering application effect，a large number of theoretical and experimental studies need to be carried out in the following directions in the later stage:optimization and development of expansive materials，expansion mechanism of expansive slurry，mechanical behavior of expansive slurry rock mass，mechanism of expansion solidification flow coupling of expansive slurry，theoretical and technical research of expansive slurry support，etc.

Research Status and Prospect of Kaiser Effect in Rock Acoustic Emission

ZHAO Kui, XIANG Weibin, ZENG Peng, YANG Daoxue, WU Wenkai, GONG Cong, YANG Xianda

2021, 50(01): 94-105.

Asbtract ( 278 )

PDF (1403KB) ( 803 )

Related Articles | Metrics

The filed in-situ stress methods have some obstacles limiting its application such as the difficulty of site operation， the complex of measurement processes，and high measurement environment requirements. Only a few on-site measurement points can be usually adopted to obtain in-situ stress information. The study on some relatively simple and easy methods for in-situ stress measurements has been an important subject of rock mechanics and engineering. The Kaiser effect of rock acoustic emission is an important method to measure in-situ stress in laboratory. The Kaiser effect of rock acoustic emission has been studied for more than half a century. But there is no acknowledged and unified method of Kaiser point identification till now. In this paper，the mechanism of Kaiser effect in rock acoustic emission，the identification method of Kaiser effect point and the factors affecting Kaiser effect are summarized and discussed. The mechanism of Kaiser effect and the evolution mechanism of microcracks are discussed. Based on the above discussion results，the main research directions and contents of the Kaiser effect of rock acoustic emission are proposed，which can provide a reference for researchers in this field.

Review on the Formation Mechanism and Early Warning of Rock Collapse

DU Yan, XIE Mowen, JIANG Yujing, CHEN Chen, JIA Beining, HUO Leichen

2021, 50(01): 106-119.

Asbtract ( 328 )

PDF (1707KB) ( 806 )

Related Articles | Metrics

As a common geological disaster in our country，the cause of the collapse is complex，the distribution range is wide，the concealment and suddenness are strong，and the damage is great. Its early warning technology has been difficult to realize. Based on the research on the causal mechanism and early warning of rock collapse disasters，it is concluded that the quantitative identification and fuzzy evaluation of rock bridges，which are the main controlling factors of collapse disasters，is the key to the early warning and prevention of rock collapse disasters in the future. Natural vibration frequency and other dynamics scientific indicators have obvious application advantages in rock bridge damage analysis，rapid identification of dangerous rocks and early warning of collapse. Besides that，paying attention to the separation stage and its separation failure precursors is one of the effective methods to improve the early warning time of rock collapse，and the establishment of the early warning method of rock collapse disaster based on the identification of separation failure precursors and the establishment of the trinity monitoring and early warning index system can change the current situation of passive prevention of brittle failure disasters. Meanwhile，it is necessary to simultaneously develop domestic high-precision remote sensing vibration monitoring technology and equipment. This is an inevitable choice for core technology innovation and development of early warning of collapse disasters to meet the strategic needs of China's engineering safety construction. Five major technical bottlenecks in the current early monitoring and early warning research of collapse disasters are summarized and the specific countermeasures are proposed. Finally，it is concluded that systematic research on the monitoring and early warning system of brittle failure disasters and realization of related technological breakthroughs will have strong theoretical significance and application value both in engineering safety requirements of the Belt and Road Initiatives and in the early warning and prevention of national geological disasters.

Study Progress and Prospect on Prevention and Control Technology of Blasting Dust and Poison in Metal Mine Stope

JIN Longzhe, GUO Jingzhong, LI Gang, WANG Tianyang, LIU Jianguo, OU Shengnan, GONG Qi, WANG Jiaying

2021, 50(01): 120-134.

Asbtract ( 288 )

PDF (3046KB) ( 731 )

Related Articles | Metrics

The prevention and control of blasting dust and poison in metal mines is an important approach to strengthen enterprises' awareness of environmental protection and to build green mines，and a inevitable demand to achieve high quality development of mine.In order to systematically study the problems and solutions of blasting dust and poison in metal mines，a comprehensive review of physical and chemical characteristics of dust，dust removal technology of water-stemming，online monitoring，and dust removal with cloudy were carried out.It is show that there are many disadvantages of dust and poison prevention and control in metal mines，such as deficiency of fundamental study and attention，imperfection of the mechanism of dust and poison prevention and control，few of prevention and control techniques，backward on grading supervision，exposure limits，testing methods and other standards，low precision of monitoring equipment of dust，the insufficient of promotion and application of new technologies and equipment for the prevention and control of dust and poison.It was reported that strengthen investigation of dust removal technology of water-stemming and cloud and online monitor of blasting dust and poison， which is an effective measure for prevention and control of blasting dust and poison at this stage.At the same time，the key study directions in the future were proposed: ① The relationship between physicochemical characteristics and wettability of typical metallic mineral dust should be studied to provide basic data and technical support for the physical and chemical elimination of blasting dust and poison；② Through the study on disinfection mechanism and formulation optimization of multicomponent water-stemming，blasting dust and poison could be reduced from the source；③ Utilize the reduction mechanism and formula optimization of roadway cloud removal technology to purify the dust and poison in the polluted air flow and reduce the air pollutants discharged to the ground；④ Online dust monitoring technology and equipment that has the advantages of high-precision，multi-point continuous measurement，resistant to pollution，and long service life，and high-precision dust monitoring system which can resist moisture，impact and other complex environments of mine should be studied and developed， so as to realize automatic and intelligent of dust monitoring；⑤ Carry out top-level design and development plans for standards，improve the system of compulsory dust monitoring standards，speed up the integration and reduction of standards as well as the work of "establishing，revising and abolishing" of standards，so as to improve their pertinence and applicability； ⑥Pay attention to the training of workers on practical operational ability from front-line，strengthen the study on the applicability of new technologies and equipment in the site，increase the popularization and application of new technologies and equipment，so as to improve the working environment of metal mines.

Research Status and Prospect of Dust Pollution Control in Typical Working Places During Mining and Transportation of Metal Mines in China

JIANG Zhong'an, ZENG Fabin, WANG Yapeng

2021, 50(01): 135-153.

Asbtract ( 329 )

PDF (8603KB) ( 797 )

Related Articles | Metrics

Dust pollution in metal mines has always affected the physical and mental health of field workers.In order to further improve the dust pollution control technology in metal mines，meet the higher level requirements of dust control，and ensure the safety of front-line operators and mechanical equipment，the status quo of dust hazards in metal mines and the development of control technology in recent years are reviewed.The development and main dust sources of occupation diseases in metal mines since 2001 were analyzed comprehensively.Principle and working principle of dust removal，spray dust suppression， foam and dust suppression agent in dust control technology were analyzed.The analysis shows that the dust control technology in metal mines is not perfect at this stage，which mainly shows that the physical and chemical properties of dust are not clear，the intelligence of dust removal equipment is poor，the dust removal system is not perfect，and the dust removal method is not environmental protection. In view of the problems existing in the research on dust pollution control technology in typical workplaces，the development directions of dust pollution control technology in metal mines are proposed in four aspects，including the establishment of dust physical and chemical property database of metal mines，the construction of mechanized，automatic and intelligent joint dust control system，the research and development of new equipment for dust prevention and control，and the development of efficient，environmentally friendly and economic water cannon mud and dust suppressor effective control of dust pollution.

Study Status and Prospect of Dust Control Technology for Metal Mines in China

LI Gang, WU Jiangyou, JIN Longzhe, GUO Jingzhong

2021, 50(01): 154-167.

Asbtract ( 404 )

PDF (4330KB) ( 771 )

Related Articles | Metrics

The dust hazard has become a prominent problem restricting the production safety，occupational health and environment of metal mines.Wet dust removal and bag dust removal techniques are adopted by the dust removal operations in most metal mines.Although the existing dust removal technique has higher dust removal efficiency，it still has the disadvantages of large resistance，high energy consumption and poor application effect.Therefore，the dust prevention and control technology of metal mines should be considered deeply.In order to further improve the mine operating environment quality， promote safe and clean production and occupational health，through systematic induction and summary of the domestic and foreign dust control technology in metal mines，the study status of the dust control technology and its applicable sites are analyzed comprehensively from six aspects of ventilated dust，closed dust control，spray dust removal dust suppressant，dust catcher and curtain separation dust.At the same time，the main problems of metal mine dust prevention and control technology at the present stage are pointed out，and the development directions of the dust control technology of metal mines are summarized emphatically.The study results show that significant progress has been made in the study of oocupational hazard control and dust control technology for metal mines in China.In the future，it should combine the characteristics of metal mine dust such as high dispersion，small particle size，high humidity and high concentration，and take high efficiency，low energy consumption，miniaturization and intelligence as the requirements to adopt a comprehensive dust-control technology means integrating effective dust control，atomization condensing，dust suppression and filtration and dust removal is adopted to achieve a breakthrough in the study and development of dust control and removal technology and equipment for effective risk control of fine dust in special environment space of metal mines，and provides theoretical and technical support for realizing scientific mining and accelerating green mine construction.

Study Status and Development Trends of Ecological Restoration Techniques in Abandoned Quarry

LI Fuping, JIA Yufei, XIA Dong, WANG Haocheng, LIU Xin

2021, 50(01): 168-184.

Asbtract ( 418 )

PDF (5477KB) ( 1193 )

Related Articles | Metrics

Limestone，as an indispensable raw material in construction and chemical industries，has a tremendous market demand，however，abandoned quarry causes serious damage to the mining district and its surrounding ecological environment. Hence，it is an effective way to build green mines that carrying out the research work of ecological restoration technology of abandoned quarries.On the basis of collecting relative information at home and abroad，the ecological restoration technologies of rock slope，working platform，pit bottom，mine road，industrial square，dump，and the surrounding area of mining boundary were summarized，and the advantages and disadvantages of the main ecological restoration techniques of rock slope and dump were analyed emphatically. In the future，the following studying contents should be strengthened: development of low-cost plant growing medium，mechanism of synergetic coupling regulation of plant growing medium-root growth， overall stability mechanism of fissured rock mass-root-plant growing medium on slope surface，crack monitoring and control and vegetation allocation mode in the dump，water-conserving and timely irrigation and maintenance technology in mining area based on 5G technology，etc..To overcome the shortcomings of traditional monitoring technology，which is difficult to achieve multi-channel and whole area coverage，5G technology，GIS and RS should be effectively combined.With the support of artificial intelligence（AI）technology，real-time dynamic monitoring should be carried out on the site conditions，soil moisture，timely irrigation and maintenance system working status，plant growth status and other aspects of the mining area， then，based on this，the restoration effect may be evaluated to achieve ecology construction of dynamic monitoring and evaluation index system of restoration integration.

Present Application Status of Rock Drilling Equipment in Underground Mine and the Development Direction for Intelligent Rock Drilling in China

WU Haojun, JI Hongguang, GONG Min, LIU Xiangyu

2021, 50(01): 185-201.

Asbtract ( 418 )

PDF (3494KB) ( 1268 )

Related Articles | Metrics

For development of large equipment，such as drill jumbos，digitalization and intelligence are the trends in future. In order to clarify the research direction of the self-developed drill jumbo，combined with the current status of the drill jumbos applied in China's underground mine，where the drilling and blasting method is used，the technical advantages and problems of drilling accuracy，drilling efficiency，safety of personnel and environmental protection indexes of the drilling platform used on site are quantitatively evaluated.Investigations results show that using drill jumbo，the drilling time for a single hole is 2~3 minutes，which drilling efficiency is 2~4 times of the one by pneumatic rock drill under the same conditions； with reasonable blasting methods，it can increase the advance per month by 50%~70%. When using the drill jumbos on-site，some problems are often existed，such as the mechanical performance do not match the drilling and blasting process， the actual over-excavation is often larger than that of pneumatic drilling，and the personnel training is fall behind its real needs.Besides that，the intelligent development progress of drill jumbos at this stage is summarized.The Research shows that through compensation，the average positioning accuracy of some cases is below 5 cm，which can meet the requirements of construction；with the help of advanced technologies such as visual aided positioning and navigation methods，5G technology and the internet of things technology，it can achieve the goal of fewer people and unmanned operations. At last，the insufficient and challenges about develop and promote the self-developed drill jumbos in future is analyzed，and the development route of self-developed drill jumbo is summarized and prospected.

Progress，Shortcomings and Prospects of Mining Science and Technology in Anhui Province:Based on the Data of Technology Awards in Mining Field in the Past 10 Years

YAO Ningguang, XU Fang

2021, 50(01): 202-212.

Asbtract ( 243 )

PDF (1587KB) ( 777 )

Related Articles | Metrics

The government science and technology award is one of the important indicators to evaluate the development level of science and technology.Based on the 2009-2019 Anhui Science and Technology Award in the mining field as a data source，statistics and analysis of the wining characteristics is done.The results show that the progress of mining technology is closely related to the development of the industry and has a lagging effect. Enterprises are the main body of scientific research and innovation in the mining industry，and the innovation capabilities of universities and scientific research institutions have been continuously strengthened.The scientific research innovations in all directions in the mining field of Anhui Province in recent ten years are summarized and analyzed.It is concluded that outstanding achievements have been made in mining and mine safety，especially in deep resource exploitation and prevention of gas and water disasters. It has developed rapidly in the direction of mine environmental protection and restoration，and achieved remarkable results in ecological damage assessment，water environment management and land restoration and utilization in subsidence areas. By summarizing the scientific and technological progress in the mining field，it is believed that there are still many problems in its development process，such as the low level of automation in the development of mineral resources，the application of modern safety monitoring technology needs to be strengthened.The low resource recovery rate，the recovery capacity of abandoned mines needs to be improved.The coordinated development of resources and the environment is facing challenge. At the same time，it is pointed out that the main innovation directions in the future mining field areless humanization，involving production， operation，and decision-making whole system of smart mine construction research.For deep resources，low-grade resources and associated resources，beneficiation and mining，research on smelting technology，improve the level of development and utilization of mineral resources. Carry out research on mine environmental damage prevention and environmental restoration for the entire life cycle of mines，and achieve mine loss reduction and non-destructive mining. Strengthen the research of the development and utilization of the closed mine resources and space，so to achieve the sustainable development and utilization of closed mine resources and space. The above analysis results can provide important data support and reference for policy making and decision-making in the mining industry and future scientific research directions in the mining field.

Table of Content