The construction principle and process of reverse construction method are introduced and its application advantages are analyzed in this paper.Reverse construction method can improve the safety of underground engineering,significantly save project costs,shorten construction period,and prevent the subsidence of surrounding foundation.It is an underground engineering construction technology that has a great development prospect and is worth popularizing.
The theory and method of optimized rock blasting are described.The optimal rock crushing principle,optimal explosive unit consumption principle,energy balance distribution principle,crushable energy band distribution principle,single-hole blasting optimal crushing principle,and surface-to-energy ratio mediatization principle for the blasting zone are proposed.Based on these principles,methods for blasting design and prediction of blasting blocks are put forward to achieve the goal of rock blasting optimization.
The straight grate technology based pellet production line faced the problem of high process energy consumption in the early stage of production.Through a series of attempts and explorations,a scheme is summarized to reduce the energy consumption of the straight grate technology based pellet production process throughout the whole process from raw materials to finished pellets,including measures such as zoned storage of iron ore concentrate raw materials,renovation of intelligent pelletizing system,optimization of induration system,and reduction of desulfurization and denitrification energy consumption.After a year of on-site practice in 2021,it's verified that the scheme to reduce energy consumption in the straight grate technology based roasting pellet process has achieved good energy-saving results.The energy consumption in the pellet process has reached 21.80 kgce/t,a decrease of 5.74 kgce/t from 2020,and the energy consumption indexes are among the best in domestic peers.
Through the exploration and practice of excavation and supporting technology for crushing chambers under underground confined space conditions in Miaogou Iron Ore Mine,an innovative excavation and supporting technology scheme for large chambers using various excavation and supporting methods has been formed,which achieves the goal of accelerating engineering construction speed and ensuring the safety and efficiency of the construction.
By utilizing the true positions of geological drillhole samples in three-dimensional space,the ore body 3D profile is contoured,and a three-dimensional solid model of the ore body is built,which more realistically reflects the occurrence state of the ore body in space,reduces the risk of inaccurate three-dimensional spatial positioning of the ore body,and solves the problem of offsetting and distortion of ore body shape.
This paper mainly discusses the current situation of tailings storage facilities in China,and introduces the main methods to close and remove the tailings storage facilities from TSF list in various provinces in China as well as a typical closing scheme of tailings storage facility in Beijing,which provides reference for similar projects.
The operation of the tertiary crushing and dry separation process is investigated and researched by Jianshan Iron Ore Mine.The magnetic declination of the dry separator is adjusted and the distance and angle of the splitter is upgraded,which achieves the goal of"ores are separated to the utmost"and"waste rocks are discarded to the utmost",decreases the separation ratio of the system,saves costs,and achieves significant benefits.
Because sintering machine works in a harsh working environment,the pallets need to be replaced frequently.This paper introduces an on-load pallet replacement technology,by which the pallets are replaced at the position of main sprockets.This scheme can avoid the"interruption in material feeds",thus avoiding the output loss caused by non-loads of the pallets and the air leakage of non-load pallets.This technology offers a new solution for the sintering industry to improve the current situation of the pallet replacement.
This paper introduces in detail the design practice of a spodumene concentrator in Sichuan in terms of the run of mine process mineralogical study,beneficiation tests,process flow design and etc.In addition,the key factors in the design of spodumene concentrator are analyzed.After the concentrator is put into operation,the production indexes of the plant site reach the designed indexes.
The properties,structure and beneficiation tests of the magnetic ore of Ansteel Group Anqian Mining Co.,Ltd are discussed in detail,and the design overview of the beneficiation process flow of the ore is introduced.
The process characteristics of the countercurrent activated carbon desulfurization and denitrification system in a pelletizing production line of a company are introduced.The activated carbon consumption of the system are mainly the two types of consumption:chemical consumption and physical consumption,and the main factors affecting the activated carbon consumption are analyzed.Combined with the pellet production process,measures such as reducing the recycling volume of activated carbon,optimizing the air volume control of the air screen dedusting facility,and strengthening the maintenance and management of the vibrating screen of the absorption tower are adopted so that the physical consumption of activated carbon is effectively reduced.The reduction of the physical consumption of activated carbon reaches 177.01 t/m,and it achieves the purpose of lowering the pellet production cost.
Based on the actual situation of occupational hazards in a certain steel rolling enterprise,the risk identification of occupational hazards in the workplace during the production process of the enterprise is carried out.The comprehensive evaluation method are used to evaluate the risk of occupational hazards in the workplace of the enterprise.Combined with the analysis results,a risk integrated management system for occupational hazards in the steel rolling enterprise are developed,and corresponding occupational hazard prevention measures are proposed.
With the continuous development of China's economy and the increasingly stringent environmental protection requirements,the national environmental policy clearly requires that new stockyards must be fully enclosed,and existing stockyards be upgraded in the specified time limit.The key construction steps of the large-span structure include ground assembly,high-altitude lifting and sliding into position.The structure is assembled on molding bed,hoisted with molding bed,and the quality and construction safety of trusses are effectively controlled with the use of the molding bed.The application of sliding technology in the project effectively saves the construction space,shortens the construction period,reduces the construction cost,and at the same time ensures that the normal production of the stockyard is not affected.
This paper introduces the working principles and technical advantages of"3S"survey technology,3D laser scanning technology and UAV tilt photogrammetry technology,and puts forward targeted suggestions according to the mining mode of the mine(open pit mining/underground mining),which can provide reference for relevant mines in the selection of digital survey technology.
Caving mining method can cause ground surface subsidence.Against the backdrop of increasingly strict national regulations on mine safety and environment protection,more and more mines are using filling mining method,and many mines have begun to transition from caving method to filling method.To ensure mining safety,barrier pillars need to be set up between the mining ranges of caving method and filling method to ensure that the two mining methods do not interfere with each other.The stability of isolation pillars is influenced by many factors.Through numerical simulation,based on the point safety degree method,the safety of barrier pillars is analyzed,and the size of barrier pillars is proposed.The research results can provide certain reference for pillar arrangement in similar mines.
In response to address the problems of the sintered ore transfer hopper of Pangang group panzhihua steel vanadium Co.,LTD like high crushing rate of the sintered ore and the large amount of dust generated by the system,a flexible transfer technology is studied and applied on the chutes P101/P201 on the finished product conveyor 3 of the new No.3 sintering machine.After implementation,the system operates smoothly and normally with load,and the overall supporting equipment for the transfer system shows no signs of jamming,blockage,or belt misalignment.The system reduces the crushing rate of sintered ores,greatly reduces the environmental dust pollution,and generates certain economic and social benefits.
With the Qijiagou gold mine in Penglai area of Shandong Province as the research object,the features of ore-controlling structures are analyzed from the two aspects of fracture occurrence and fracture dynamics.Based on the distribution characteristics of gold ore bodies revealed by existing geology and mining engineering,the control effect and ore-controlling laws of fault structures on the ore bodies are summarized,and the control effect of three tensile and torsional structural combinations in the NNE,NE,and NEE directions on the ore bodies is identified,which has guiding significance for the exploration of gold deposits in the region.
A large-scale underground iron ore mine is introduced in this paper.Based on the characteristics of the ore deposit and production process,and with the planning and process control as the priority,a ore supply and blending management system that focuses on the three key control links of ore blending in the mining area,ore blending in the shaft,and dry separation for quality improvement is established.Through practice,the management level of ore supply and blending is continuously improved,and the operation and production of the concentrator have been stabilized,thus improving the overall economic benefits of the enterprise.
数码电子雷管的推广应用,一方面使用环境与新产品的适应性存在差异性问题,另一方面新产品能较好地解决非电起爆网络无法处理的爆破技术瓶颈问题.从露天金属矿山难爆岩的爆破效果优化和掘进爆破盲炮的避免两个方面阐述了数码电子雷管的优越性,通过克服井下采场的磁电、杂散电流干扰和长距离起爆阐明了数码电子雷管的优越性.
