Research on short wall continuous mining technology with full roof falling and roof control measures

2021 ◽  
Author(s):  
Shuli Wang ◽  
Guangli Zhu ◽  
Kaizhi Zhang ◽  
Yuchen Wang
Keyword(s):  
Control Measures ◽  
Mining Technology ◽  
Continuous Mining ◽  
Roof Falling

The shift step optimization of belt conveyor in self-advancing semi-continuous mining technology based on SIMIO

2017 ◽  
Vol 14 (4) ◽  
pp. 324-328
Author(s):  
Xinwang Li ◽  
Li Li ◽  
Huayong Lv ◽  
Tianqiang Guan
Keyword(s):  
Computer Simulation ◽  
Open Pit ◽  
Computer Simulation Model ◽  
Belt Conveyor ◽  
Modeling Framework ◽  
Mining Technology ◽  
Content Type ◽  
Continuous Mining ◽  
Mining Width ◽  
Operational Modes

Purpose This paper aims to develop a computer simulation processing method to simulate the mining operation of self-advancing semi-continuous mining technology and optimize the shift step of belt conveyor by using simulation modeling framework based on intelligent objects (SIMIO). The method would effectively solve the challenge of field testing such large-scale equipment. Design/methodology/approach The four operational modes of self-advancing semi-continuous mining technology at single bench had been illustrated. The operational system of this technology was analyzed and broken down to single units. By analyzing the time constitution of one operation cycle, the theoretical optimization model of shift step can be established and the optimization criteria is the time utilization ratio being maximum. Once the simulation flow was determined, a three-dimensional (3D) computer simulation model of this mining technology was developed by adapting the SIMIO simulating software to the theoretical model. The models were run to investigate the outputs from different operational modes using geological and mining data from East open-pit mine. Findings The result of these simulations showed that the four-mining-width one-shift (FMWOS) is at maximum production capacity during all operation modes. If transfer equipment is necessary, then this mode can adapt, but system will become more complex. There are minor differences between two-mining-width one-shift and three-mining-width one-shift. If transfer equipment is not necessary, then the two-mining-width one-shift can adapt during actual production. Originality/value The simulation results show that the proposed method can achieve the optimal shift step of a belt conveyor and effectively reduce the time loss caused by the coordination of multiple pieces of equipment while simultaneously improving operational efficiency.

scholarly journals Cemented Backfilling Mining Technology for Gently Inclined Coal Seams Using a Continuous Mining and Continuous Backfilling Method

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Bin Lu ◽  
Yongliang Li ◽  
Shizheng Fang ◽  
Hai Lin ◽  
Ye Zhu
Keyword(s):  
Surface Deformation ◽  
New Technology ◽  
Engineering Application ◽  
Filling Material ◽  
Coal Seams ◽  
Mining Technology ◽  
Coal Resources ◽  
Continuous Mining ◽  
Material Transportation ◽  
Coal Pillars

To improve the efficiency and reduce costs of cemented-fill mining, we propose a continuous mining and continuous backfilling (CMCB) method based on the coal resources at the Yuxing mine in Inner Mongolia, China, and constructed a complete filling material transportation system. The new technology is suitable for cemented-fill mining of gently inclined coal seams. Numerical simulations were performed to investigate the dynamic migration law of surrounding rock stress using CMCB cemented-fill mining technology, and similar simulations were conducted to analyze the movement characteristics of the coal overburden. The results show that the coal pillars and filling body alternately bear and support each other during the CMCB process, which resolves the contradiction between mining and filling, achieves parallel mining and filling operations, and improves mining efficiency. The new mining mode exerts minimal disturbance to the overlying rock and effectively controls surface deformation. The engineering application of this technique is promising and provides theoretical guidance and technical support for safe and efficient mining of the same type of coal resources.

Research on Cooperated and Continuous Non-Pillar Mining Technology

2013 ◽  
Vol 295-298 ◽  
pp. 2906-2912
Author(s):  
Zhou Ke Guo
Keyword(s):  
Adverse Impact ◽  
Gas Content ◽  
Mining District ◽  
Mining Technology ◽  
Marginal Basin ◽  
Geological Features ◽  
Adjacent Face ◽  
The Face ◽  
Continuous Mining ◽  
Pillar Mining

This thesis, making research on 4224 Mining District of Zhangcun Mine and combining with the geological features of the good lithological conditions of the roof and floor of the mining district and low gas content，etc, put forward the maintain roadways pattern of gob-side entry retaining, adopt adding anchor cables and erecting monomer pillar and other methods as the means to strengthen support, and effectively prevent the gangue to flow into the roadway by hanging grid on the up-side, and make research on ground behavior regular of gob-side entry retaining. Raise the transporting method that the face support move along the Gob-side Entry to the Open-Off Cut of the next section，which shorten the face moving route and moving time, achieve quick successival of the adjacent face. Meanwhile, continuous mining makes the surface appear continuous sinking, avoid the adverse impact on the surface of the sinking marginal basin, and minimize damage to the environment. Achieve the maximum recovery of coal resources, and minimize damage to the environment.

scholarly journals Dynamics of vibratory partitioned feeders for the uranium ore drawing and feeding

2019 ◽  
Vol 109 ◽  
pp. 00023
Author(s):  
Vitalii Dyrda ◽  
Anatolii Kobets ◽  
Viktor Pukhalskyi ◽  
Yurii Kozub ◽  
Oleksandr Chernii
Keyword(s):  
Rock Mass ◽  
Labor Intensity ◽  
Mining Operations ◽  
Mining Technology ◽  
Uranium Ore ◽  
Discharge Opening ◽  
Continuous Mining ◽  
Elastic Couplings

In this paper, the authors consider dynamics of partitioned vibratory feeders with rubber elastic couplings. Use of vibratory feeders (including partitioned ones) and schemes for the ore vibrating drawing, feeding and loading in underground conditions allowed to mechanize one of the most time-consuming and dangerous processes of uranium ore mining and to solve the following problems: to improve effectiveness of the lumpy rock mass drawing and loading by 2.5-3 times; to increase intensity of mining operations and reduce life of the excavation blocks and horizons; to reduce labor intensity and cut cost of the process of ore drawing and loading; to improve uniformity of the rock-mass outflowing from the discharge opening and to reduce by 3-5 times frequency of the large-lump material freezing (use of partitioned feeders reduces number of freezes by 25-60 times); to increase size of commercial lump panels; practically to exclude traumas during the process of ore drawing and loading (usually, it presents 30-60 % of all traumas caused by the underground operations); to mechanize process of ore drawing and loading, and to create conditions for implementation of low-waste cyclic-and-continuous mining technology.

scholarly journals Research on Continuous Miner Mining with Backfilling Technology under High Geostress and Complex Conditions

2020 ◽  
Vol 165 ◽  
pp. 03042
Author(s):  
Du Tao
Keyword(s):  
Field Application ◽  
Burial Depth ◽  
Mining Technology ◽  
Coal Resources ◽  
Continuous Miner ◽  
Working Face ◽  
Geological Conditions ◽  
Deformation Speed ◽  
Continuous Mining ◽  
High Geostress

Aiming at the mining seam with large burial depth, strong geostress, large deformation of the roadway, and fast deformation speed, in order to efficiently recover the coal resources at the working face and effectively protect the surface buildings. Based on analyse of the law of the appearance of the underground roadway pressure in the relevant working face, combined with continuous miner mining technology and equipment technical characteristics, this paper proposes to use a combination of continuous miner mining technology and backfilling technology to mine under high geostress geological conditions. And optimize the mining process parameters according to the field application. The results show that the continuous mining miner with backfilling method can achieve the efficient recovery of coal resources under high geostress and complex conditions.

MEASLES OUTBREAK IN A RURAL AREA OF A DEVELOPING COUNTRY: A CASE CONTROL STUDY

2018 ◽  
Vol 7 (4) ◽  
pp. 197-201
Author(s):  
Mir M Hassan Bullo ◽  
Mirza Amir Baig ◽  
Jawad Faisal Malik ◽  
Ejaz Ahmad Khan ◽  
Muazam Abbas Ranjha ◽  
...  
Keyword(s):  
Risk Factors ◽  
Vaccine Coverage ◽  
Significant Risk ◽  
Public Health Problem ◽  
Maculopapular Rash ◽  
Healthcare Facility ◽  
Control Measures ◽  
Major Public Health Problem ◽  
District Health ◽  
Active Case

Background: Measles is highly contagious vaccine preventable disease (VPD), and a major public health problem considered as leading cause of morbidity and mortality in developing countries like Pakistan. An outbreak of measles was reported in Sharifabad Islamabad on 15th of April 2017, and an investigation was launched to assess the magnitude of outbreak, evaluate risk factors and recommend control measures. Methods: A comprehensive house to house active case search along with vaccine coverage survey was conducted from April 19-22, 2017. A case was defined as "onset of maculopapular rash with fever in a resident of Sharifabad with at least one of the following signs/ symptoms, Coryza, Conjunctivitis, Cough, Otitis media or Pneumonia present in between 19 March to 22nd April 2017". Four age & sex matched controls were selected from the neighborhood. Data was collected through interview method using structured questionnaire and vaccination coverage was determined by using Epi survey form. Blood samples were sent for laboratory confirmation. Results: A total of eight cases were identified through active case finding while three were reported by local practitioner. Mean age of cases were 20 months (range 8-36 months). Severely affected age-group was 1-2 years with attack rate of 46%. Around two-third (64%) of cases and a few (16%) of controls were unvaccinated against measles. Contact with measles patient [OR 25.2, CI 3.9-160.1, P=0.00], unvaccinated children [OR 9.2 CI 2.12-40.4, P=0.000], social misconception regarding vaccination [OR 7.8 CI 1.42-42.6, P=0.00], and distance from healthcare facility [OR 5.7 CI 1.15-28.35, P=0.02] were significant risk factors. Vaccine efficacy was 90%. Conclusion: Main reasons of the outbreak were contact with the cases, and low vaccination status. We recommended comprehensive measles vaccination and community awareness sessions. On our recommendations district health authority Islamabad carried out mop up of whole area.

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