Roof filling control technology and application to mine roadway damage in small pit goaf

To recover coal resources that have been damaged by traditional mining methods and ensure stability of the lower roadway in a small pit goaf,the goaf area must be filled and reinforced.In this research,the 1202 working face of the Hanzui mine is considered as an example for classifying the roof of the mining tunnel under the small kiln destruction zone,the effect of the goaf on the roadway is determined based on the radio tunnel penetration method,a mechanical model to determine the roof filling control mechanism was established,and the duct foaming system and roof filling process were designed.The results show that the scope and degree of influence of the goaf on the mining lane are large,but safe tunneling can be ensured through the use of a steel shed and advanced grouting techniques.When the roof conditions are not similar,materials with different filling heights and filling strengths can be used to control the roof filling of the roadway.By combining field experience and laboratory tests,it was determined that a high-foaming material with a water-cement ratio of 1:0.6,a suitable high-foaming additive,and a water volume ratio of 1:30 is cost-efficient for filling and meets the filling strength requirements.Finally,the reliability of the proposed technology was verified by field experiments,which provide a reference for filling operations in similar mines.

OPTIMUM CONTROL ON MINING RATE OF MINERAL RESOURCES

Several model are built to search optimum mining rate by rising optimum control theory Sor various purpose, A numerical method is extracted to assist both planer and decision maker of mining in their planing or scheduling work.

Double-directional control bolt support technology and engineering application at large span Y-type intersections in deep coal mines

Under deep and complex geological conditions,severe deformation occurs at intersection points of Y-type roadways with large cross sections during engineering projects in coal mines,especially at junction arches.Based on in-situ investigations and theoretical studies,we have summarized typical forms of destruction and identified high stress and unrestricted support at both sides of junction arch as its main causes.In this study,we also presented double-directional control bolt support technology for a large Y-type span intersection,applied to deep intersection engineering in the Jiahe Coal Mine,which has proved effective.

PREDICTION AND CONTROL OF ROCKBURST DURING DEEP EXCAVATION OF A GOLD MINE IN CHINA

The studies of prediction and control of rockburst are presented during deep excavation in a gold mine in China. Firstly,the stress-relief method is used to obtain a vast amount of data about initial geostress. Secondly,3D FEM analyses of large scale are performed to find out the law of geostress distribution at various excavation levels of the mining area. At the same time,as an equally important measure,six typical kinds of rock blocks are sampled for the experimental study of rockburst tendency. According to the synthesized results of the theoretical and testing results,the methods of brittleness coefficient,brittle index and stress,and so on,are adopted. Finally,the evaluation on the possibility of rockbursts is given that may take place at the deep mining area and some effective measures are put forward to prevent and control the rockburst.

基于3Dmine的矿山防治水分析应用模型建立与研究

矿山三维建模是建设数字矿山的重要手段,文章通过3Dmine矿业工程软件创建了莱新铁矿防治水分析应用模型。在收集矿山地质勘察、巷道、钻孔、涌水量等资料的基础上,进行了数字化工作并建立相关数据库,从而构建了矿山三维地质模型、矿体模型、巷道模型及钻孔涌水模型4个部分,并利用涌水来衡量模型的合理性。模型实现了真实直观的井下近矿体帷幕工程三维可视效果,将有利于矿床水文地质条件分析、防治水工程的设计与研究以及工程稳定性评价等工作。

基于DataMine的自动化品位控制建模软件功效及应用——以纳米比亚湖山铀矿为例

纳米比亚湖山铀矿的矿体结构复杂,分支复合较为常见,矿岩界线随上下岩性组合多变,采矿生产对品位控制模型的依赖较大。传统品位控制模型的构建步骤较为复杂且耗时较长,对操作人员的技术能力要求较高,明显制约采矿生产的降本增效。针对湖山铀矿的矿体和工程特征,在DataMine矿业软件平台上利用JavaScript语言开发了自动构建品位控制模型的插件。该插件通过调用DataMine内部函数,按照既定的建模技术流程和估值参数方案一键完成基础数据导入、钻孔组合、特高品位处理和样品等长组合等全部工作流程,运用最近距离法划分矿化域的功能,替代传统手工圈定矿体,可实现自动调取估值参数构建品位控制模型的功能。该插件不但简化建模步骤,显著缩短建模耗时,而且匹配矿山日常生产的实际情况和操作习惯,经过生产检验满足生产需求。

Training of Infection Prevention and Control to Healthcare Workers of Mining Health Facilities: A Shared Responsibility for Improving Safety of Mining Communities

Introduction: Without appropriately trained healthcare workers (HCWs), infection prevention and control (IPC) cannot be implemented according to set standards. Although training is crucial, authorities rarely consider those working in health facilities owned by the mining. We describe the training which was conducted in North Mara in Mara region mining health facilities. Methods: This was descriptive study on the training of IPC to HCWs of mining health facilities. The training was conducted to North Mara Gold Mine Limited on April 2024. We targeted the HCWs and supporting staff working in the health facilities of the mining communities. The duration of the training was five days. The sessions started with pre-training test to evaluate what participants understood before training and followed with training itself. The training was carried out using mixed adult learning methods like: illustrated lectures, demonstrations, brainstorming, small group activities, group discussions, role plays, case studies and simulations. The training was finalized with posttest. Results: A total of ten HCWs were trained out of 13 of the facility. In that training six were males and four were females. Also, out of the ten trained three were clinicians, four nurses, one lab technician, one pharmaceutical technician, one support staff. The average score of the results of the pretest was 70.7% with a range of 16% (minimum 64% and maximum 80%) and that of the posttest was 79.8% with a range of 12% (min 74% and max 88%). Conclusions: If HCWs are well trained to comply with IPC standards and transmission-based precautions, they have the ability to deliver safe health services and protect themselves, patients, environment and the community. Training of HCWs working at the mining, therefore, can be adapted in all mines to improve the quality of mining healthcare and respond to the need to improve the safety of mining communities.

基于数据挖掘模型的智能插秧机作业实践探究

以进一步优化插秧机的整机作业效率为研究目标,选取插秧机智能控制系统为研究对象,基于数据挖掘模型及算法理念展开实践应用探究。结合插秧机的作业特征及网控系统结构原理,从降低网络信号传输延迟及提升抗干扰能力角度搭建数据挖掘算法优化模型,并进行实际的插秧状态算法路径设计及控制指令下发,确保各个环节衔接准确。插秧作业结果表明:基于数据挖掘模型的插秧机智能化作业水平得到显著提升,挖掘算法精度与系统控制准确率分别可相对提升7.90%和5.75%,整机插植均匀度可达90.72%,对于插秧机的智能化开发与优化具有促进作用。

基于3Dmine的采空区治理工程实践

通过对某金矿采空区资料收集及现场调查,利用3Dmine软件建立了该金矿采空区+巷道三维数字模型,准确获得了各中段采空区的实际边界和采空区形态等相关信息。针对采空区情况,结合矿区生产实际,经综合分析研究,提出了采空区治理方案,即:对矿区已经贯通连成一体的采空区群/塌陷坑(四中段以上)采用地表废石充填,四中段未贯通的采空区采用中深孔强制崩落顶板,将上部自地表“灌入”的废石充填到采空区,同时采取密闭隔离的方式联合治理;对于其余地段的采空区,已经结束回采且无法进入的区域采取在中段石门密闭隔离的方式进行治理,尚在开采的其他采空区采取施工措施工程进行坑内毛石回填并密闭隔离方式治理。通过多项措施的综合运用,彻底消除了发生大面积地压活动并引起地面塌陷的隐患,为井下正常生产作业创造了良好的条件。

基于可编程逻辑控制器的煤矿综采组合开关结构设计

针对有效、统一控制煤矿综采工作面多种采煤设备为目的,设计基于可编程逻辑控制器的煤矿综采工作面配套组合开关结构。该开关结构分为主控制电路、次控制电路,两种电路均与液晶显示模块相连。通过液晶显示模块的界面将电路状态反馈给管理人员,两种控制电路主要通过可编程逻辑控制器和继电器、信号提醒、保护回路相连,分别完成电源供应、警报信息提醒、采煤设备连接状态管理。实验结果表明,在过载、漏电工况中可用电气互锁的方式保证采煤机状态不出现异常变化,完成异常采煤设备的统一管理,最高节能比例达到11.2%,最低节能比例也能达到7.8%,由此证明设计的方法具有一定研究价值。

综采工作面过大落差逆断层回采技术研究与应用

落差较大的断层,严重影响采煤工作面的安全生产。逆断层在永夏矿区较为罕见,车集煤矿2902工作面切眼为矿井首次揭露大落差逆断层,通过对大落差逆断层回采技术难题研究分析,对工作面爆破机理及效果反向分析总结,对综采工作面爆破规律摸索,优化了爆破参数及爆破防崩措施;合理控制回采层位,减少了破岩量;制定了托顶煤控制措施,有效实现了安全快速通过逆断层,对类似构造煤层开采具有较强的参考价值。

店坪煤矿长距离巷道高精度贯通测量技术与应用

为保证店坪煤矿830水平南翼大巷贯通导线测量的顺利实施,对店坪煤矿地面控制系统、主斜井及副斜井、830南翼大巷超长距离贯通测量技术方案设计实施和优化进行了研究。通过对控制导线长、副斜井风大、延伸大巷起伏等观测条件复杂等技术问题与不便因素分析探讨。采用GPS高精度测量、陀螺定向测量、应用五连架法附及原有固定边检验法等先进有效的测量技术,分析确定本次贯通测量方案,并进行贯通误差预计。导线贯通闭合后,有效验证贯通设计中各项参数取舍的合理性,贯通精度显示,贯通测量技术方法及成果整体可靠,为二采区采掘面的准确贯通奠定高精度控制导线基础。

煤矿综合自动化控制系统平台软件Auto-mine

叙述了北阳庄煤矿综合自动化控制系统平台软件Auto-mine技术原理及方案。主要包括Auto-mine矿井综合自动化平台软件技术特点、体系结构、功能、关键技术及产品。

PDMiner平台的主动配电网安全监测系统

主动配电网系统结构复杂、DG渗透率高、负荷波动大、控制要求严格,运行数据信息呈现出大量、高速、多样和价值的特点。针对主动配电网大数据处理的问题,依据云计算理论,采用数据挖掘技术和分布并行计算方式,建立了一套PDMiner大数据挖掘平台的主动配电网安全监测系统模型。分别研究了系统对历史数据和实时故障数据的处理。研究表明该系统通过对历史数据的处理可进行风险区域划分、制定规划方案、运行状态评价,通过对故障数据的处理可进行故障分析与处理,并为配电网安全改造提供依据。通过仿真算例验证了该系统的工作效果。

Longwall surface subsidence control by technology of isolated overburden grout injection

Surface subsidence is a typical ground movement due to longwall mining, which causes a series of environmental problems and hazards. In China, intensive coal extractions are commonly operated under dense-populated coalfields, which exacerbates the negative subsequences resulted from surface settlement. Therefore, effective approaches to control the ground subsidence are in urgent need for the Chinese coal mining industry. This paper presents a newly developed subsidence control technology: isolated overburden grout injection, including the theory, technique and applications. Relevant procedures such as injection system design, grouting material selection, borehole layout, grout take estimation and injection process design are proposed. The applicability of this technology has been demonstrated through physical modelling, field measurements, and case studies. Since 2009, the technology has been successfully applied to 14 longwall areas in 9 Chinese coal mines. The ultimate surface subsidence factors vary from 0.10 to 0.15. This method has a great potential to be popularized and performed where longwall mining are implemented under villages and ground infrastructures.

Mining subsidence control by solid backfilling under buildings

Solid backfilling mining can reduce the buildings' damage caused by mining greatly. The reduction of subsidence value, the slow advancing speed and the subsidence caused by backfilling body compaction are the main reasons that solid backfilling mining velocity decreases significantly. Based on the research of mechanism, some principles on subsidence control of solid backfilling mining under buildings were proposed. The equivalent mining height was designed according to the fortification criteria of buildings and their attachment structures, which enables the ground movement and deformation caused by mining to be less than the corresponding fortification criteria.

Undersea safety mining of the large gold deposit in Xinli District of Sanshandao Gold Mine

The exploration of undersea resources becomes popular as land resources decrease. Researches were conducted with emphasis on the safety and efficiency of undersea mining of the large gold deposit in Xinli District of Sanshandao Gold Mine. A series of tests for the physical and mechanical characteristics of rock mass were carried out, and the three-dimensional geo-stress distribution was tested in the mining area. Further, a similar experimental simulation platform, which revealed the mechanism of water inrush and ascertained the reason- able thickness of the safety isolate layer, was established for the undersea mining. Meanwhile, the feasibility of cancelling the ore pillars and the safety conditions was checked by numerical simulation. The simulation results show that it is safe to exploit the ore body below the -85 m level （presently, the exploitation level is below -160 m in Xinli District）, and the ore pillars can be cancelled below the -560 m level. Fur- thermore, a novel backfill method was designed to reduce the rock strata disturbance and settlement, and the settlement of roof strata was monitored during the mining process. Engineering practice shows that the settlement of roof strata was small and that no disaster happened. This indicates that the undersea safety mining technology of the large gold deposit is achieved in Xinli District.

Characteristics of rockburst and its mining technology in mines

In order to resolve how to mine under the condition of high stress with rockburst, this paper analyzes the law of rockburst, and considers that most of the rockbursts occur in the high stress area of stope. A method of rockburst forecast and its steps are given, and three different stages of rockburst are identified. Furthermore, this paper considers that blasting energy can effectively control rockburst by changing the characteristics of rock mass, which decreases the probability of rockburst happening. According to characteristics of rockburst, two feasible mining techniques under rockburst conditions are put forward, that is stoping and filling method, and sublevel caving method of mining without any sills in hanging wall.

Underground ground control monitoring and interpretation,and numerical modeling, and shield capacity design

Mine or longwall panel layout is a 3D structure with highly non-uniform stress distribution. Recognition of such fact will facilitate underground problem identification/investigation and solving by numerical modeling through proper model construction. Due to its versatility, numerical modeling is the most popular method for ground control design and problem solving. However numerical modeling results require highly experienced professionals to interpret its validity/applicability to actual mining operations due to complicated mining and geological conditions. Underground ground control monitoring is routinely performed to predict roof behavior such as weighting and weighting interval without matching observation of face mining condition while the mining pressures are being monitored, resulting in unrealistic interpretation of the obtained data on mining pressure. The importance of ground control pressure monitoring and simultaneous observation of mining and geological conditions is illustrated by an example of shield leg pressure monitoring and interpretation in an U.S. longwall coal mine: it was found that the roof strata act like a plate, not an individual block of the size of a shield dimension, as commonly assumed by all researchers and shield capacity is not a fixed property for a longwall panel or a mine or a coal seam. A new mechanism on the interaction between shield's hydraulic leg pressure and roof strata for shield loading is proposed.

Method for prevention and control of spontaneous combustion of coal seam and its application in mining field

Spontaneous combustion of coal seam has been and continues to be a big problem in coal mines. It could pose great threat to the safety of the whole mine and all miners, especially when it occurs in or nearby coal mines. Besides, environment of area surrounded mines during combustion can be threatened where large amount of toxic gases including CO_2, CO, SO_2 and H_2S can be leased by fire in mine. Hence, it is important and significant for scholars to study the controlling and preventing of the coal seam fire. In this paper, the complicated reasons for the occurrence and development of spontaneous combustion in coal seam are analysed and different models under various air leakage situations are built as well. Based on the model and approximately calculation, the difficulty of fire extinguishment in coal seam is pointed out as the difficulty and poor effect to remove the large amount of heat released. Detailed measurements about backfilling and case analyses are also provided on the basis of the recent ten years' practice of controlling spontaneous combustion in coal seams in China. A technical fire prevention and control method has been concluded as five steps including detection, prevention, sealing, injection and pressure adjustment. However, various backfill materials require different application and environmental factors, so in this paper, analyses and discussion about the effect and engineering application of prevention of spontaneous combustion are provided according to different backfilling technologies and methods. Once the aforementioned fire prevention can be widely applied and regulated in mines, green mining will be achievable concerning mine fire prevention and control.