Engineering Commons^™

Suppression Of Multiple Reflected Refraction In Shallow Low-Velocity Zones By Vertical Combination Of Seismic Sources, Fu Yanning, Chang Suoliang, Zhang Sheng, Liu Zuiliang, Yang Yong, Chen Qiang, Liu Bo, Xu Yuying

Coal Geology & Exploration

A special type of multiple reflected refraction often appears in seismic records in areas with low-velocity structures. It seriously affects the closed reflection wave, which causes the distortion of the reflection wave shape and affects the correct interpretation of the seismic data. Based on the forward simulation of the multiple reflected refraction equation, the generation mechanism of multiple reflected refraction in the shallow low-velocity zones was set forth. A method of suppressing multiple reflected refraction by vertically combined dual sources was proposed. The formation parameters(formation thickness and velocity)are obtained according to the methods of small refraction and micro logging in …

Seismic Impedance Inversion Of Coal Field With Reflectivity Method Based On Bayesian Theory, Yang Zhen, Gao Zhenyu, Liu Xingye

Coal Geology & Exploration

Seismic inversion can reflect the morphology of subsurface formation and facies information more intuitively. Seismic impedance inversion can directly produce elastic information of underground media, providing reliable information for subsequent coal identification, water channel prediction and collapse column distinguishing. A Bayesian-based inversion of reflectivity method was developed. It can consider the various propagation effects of seismic waves and solve the objective function nonlinearly, which can more accurately calculate the impedance and improve the inversion resolution. The method is applied to the actual data from Buertai coal mine and satisfactory results are output, which effectively verifies the feasibility and effectiveness of …

Research On Electronically Controlled Automation Technology Of Underground Drilling Rig For Coal Mine, Dong Hongbo, Yao Ningping, Ma Bin, Liao Jiangnan

Coal Geology & Exploration

In order to conform to the development direction of automation and intelligence of underground equipment in coal mines, a set of electronically controlled system of drilling rig has been developed according to the characteristics of underground drilling rigs in coal mines. The functions such as remote control, parameter monitoring, working condition judgment and safe interlocking were realized in the drilling rig. On the basis of single-acting control of the drilling rig, the technology of automatic drilling and automatic trip-out of the drilling rig was studied, which greatly improved the automation of underground drilling rig in coal mine. The functional experiments …

Design And Numerical Simulation Of Multi-Layer Bit With Extra-High Matrix, Sun Qibin, Shen Lina, Yang Gansheng, Tian Guoliang, Ruan Hailong, Chen Xi

Coal Geology & Exploration

Aiming at the problem that the life of the diamond bit is limited by the height of the bit matrix, an optimized design scheme of an impregnated diamond bit with extra-high multi-layer matrix was proposed. In the design of the bit, eccentric staggered cutting teeth, alternate waterways and water baffles were introduced to ensure the cooling and effective drilling of the bit. Through strength and hydraulic flow field simulation, the strength of the drill bit was checked, the rationality of the waterway structure was verified, and the finished product of the drill bit was further realized. The drill bit breaks …

Analysis Of Paleoclimatic Cycles In The Ultra Thick Coal Seam Of Yan'an Formation In The Southern Ordos Basin, Dong Guoqi, Wang Dongdong, Liu Haiyan, Mao Qiang, Yin Lusheng

Coal Geology & Exploration

Coal is a climate-sensitive sediment that contains abundant paleoclimate information. In order to find out the paleoclimate information contained in the coal seam and the evolution of its controlling factors, the No.4 thick coal seam in the first member of Yan’an Formation in the south of Ordos basin was studied. Based on the intensive sampling of the thick coal seam, the information of organic macerals, major and trace elements, and stable carbon isotopes of organic matter were systematically tested. By using the macerals, characteristic elements and carbon isotopes of coal and rocks, four cycles of paleoclimate with alternation of warm-wet …

Change Law Of Adsorption/Desorption Energy Of Coal With Different Water Content Under The Action Of Far Infrared, Ma Kai, Ma Qianqian, Shi Yongtao

Coal Geology & Exploration

The essence of coal gas adsorption/desorption process is the process of interaction between gas molecules and molecules or atoms on the surface of the coal matrix, and the nature of the interaction is energy change. In order to deeply study the coalbed gas adsorption/desorption rules and energy change rules under the action of far infrared, the self-developed device was used to perform CO₂ adsorption/desorption experiments on coal samples with different water contents under the action of far infrared. Then, the experimental results are calculated using the adsorption/desorption energy change model obtained from the principle of far-infrared thermal radiation, and …

Acoustic Emission Characteristics And Damage Evolution Of Coal-Rock Under Different Confining Pressures, Yu Jie, Liu Xiaohui, Hao Qijun

Coal Geology & Exploration

Using PCI-2 acoustic emission(AE) system, the AE experiments of different confining pressures (0, 8, 16, 5 MPa) were carried out in Baijiao coal mine in Furong, Sichuan Province, in order to reveal the change rule of ringing count rate, the temporal and spatial distribution of AE, b value of AE and damage characteristics of damaged coal-rock under different confining pressures, and to provide a theoretical basis for prediction of coal-rock damage. The results show that the AE phenomenon can reflect the crack propagation of coal-rock and the confining pressure can restrain the damage of coal-rock. With the increase of confining …

Model-Driven Energy Attenuation Method For Coal Seam Strong Reflection, Zhang Xianxu

Coal Geology & Exploration

The reflection of coal seam in seismic data has the characteristics of strong energy, which makes the reflection of adjacent strata often concealed by the reflection of coal seam. This makes it difficult to image the adjacent weak layer and lithological interpretation difficult. Aiming at this problem, a model-driven energy attenuation method for coal seam strong reflection was proposed. This method uses the coal thickness calculated by logging and measured by borehole in underground coal mine to construct cross plot with reflection amplitude of coal seam, and fit the relationship formula between amplitude and thickness. The digital model was constructed …

Influence Of Water Injection In Burst-Prone Coal Seam On Suction And Sticking During Drilling, Hao Zhiyong, Li Zhiwei, Pan Yishan

Coal Geology & Exploration

When the spiral drill pipe is used to predict and evaluate the dynamic disasters such as rock burst, the drilling dynamic phenomena such as suction and sticking are easy to occur. In order to study the influence of water injection in burst-prone coal seam on suction and sticking, the mechanism of dynamic phenomenon of suction and sticking was analyzed by establishing the mechanical model of drill pipe, pointing out that the stress of coal body and the amount of drilling cuttings are the important factors that affect the occurrence of suction and sticking, deriving the calculation formula of drilling mechanical …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

The Structural Characteristics And Their Influence On Production Of Buliangou Coal Mine, Ma Liang, Guo Rui

Coal Geology & Exploration

Jungar coalfield is located at the turning point of Yimeng uplift and Jinxi flexure belt in Ordos basin. There are many kinds of mine structures in the coalfield, and the structural complexity has changed greatly before and after the exposure by mine production. Taking the fold, fault, karst collapse column, igneous rock intrusion and other geological structures exposed by geological exploration and mining as the research object, quantitative or semi-quantitative evaluation of structural development characteristics in the mine was carried out by means of mathematical statistics, and the formation mechanism, evolution background of different geological structures were analyzed. The main …

Experiment Of Mesostructure And Hydrologic Characteristics Of Weakly Cemented Soft Rocks In Western China, Zhang Jiafan, Cheng Shufan, Wang Huan, Gao Zhuang, Zhou Feiwen, Zhou Hongwen

Coal Geology & Exploration

In order to accurately grasp the hydrologic characteristics of weakly cemented soft rocks in western China, the hydraulic and mechanical properties of red sandstone collected from northern Shaanxi mining area were tested. Based on the scanning image of scanning electron microscope(SEM), the mesostructural characteristics of the rocks were analyzed, and the relationship between the mesostructure of rocks and its macroscopic hydrologic characteristics was established. The results show that red sandstone has obvious characteristics of water saturation and water absorption and expansion, and its softening coefficient is 0.64. Under the action of pressure water erosion and dry and wet cycle, the …

Exploration And Quantitative Evaluation Of Overburden Strata “Three Zones” In Deep Strip Mining, Liu Zhen, Wang Yutao, Liu Xiaoping, Wang Xiaodong

Coal Geology & Exploration

In order to study the height of overburden fractures in deep strip mining, engineering geological drilling, borehole television and coalfield well logging have been applied to detect and analyze the overburden fractures in a coal mine in Jining coalfield. The results indicate that, under the strip mining with gentle dip(6°), deep depth(538 m) and 1:2 mining-retention ratio(mining -50 m and remaining -100 m), the “three zones” develop prominently, presenting “wavy” destruction in space, and the goaf has no obvious cavity. The height of caving zone is 8.45 m which is 3.0 times of the mining height, and the fault zone …

Production Decline Law And Influencing Factors Of High-Rank Coal Cbm Wells, Jia Huimin, Hu Qiujia, Mao Jianwei,, Mao Chonghao, Liu Chunchun, Zhang Qing, Liu Changping

Coal Geology & Exploration

In order to reveal the production decline law of high-rank coal CBM wells, based on the development data of Fanzhuang block in southern Qinshui basin for more than 10 years, this paper studies the decline point, decline type and influencing factors of high-rank coal CBM wells by means of numerical simulation and statistical analysis. The results show that the decline point of the Fanzhuang block is 25% and the average decline point of the single well is 21%. Most wells begin to decline after drainage of 4 years. The decline point of CBM well is determined by matrix permeability and …

Fracturing Parameters Analysis And Productivity Evaluation Of Vertical Coalbed Methane Wells With Nitrogen Foam, Li Hengle, Cao Yunxing, Zhou Dan, Chai Xuezhou, Liu Tongji, Feng Peiwen, Shi Bin, Tian Lin

Coal Geology & Exploration

Fracturing parameters are important parameters that affect the fracturing effect, fracture characteristics and CBM productivity. Through an in-depth understanding of the influence of fracturing parameters on productivity, it is essential to optimize the fracturing process and increase the productivity of CBM wells. Taking 45 nitrogen foam fracturing wells in Lu’an mining area as the research object, the types of fracturing operation curves and their effects on productivity were studied. The relationship between fracturing fluid dosage and productivity was discussed. The differences in productivity of nitrogen foam wells and hydraulic fracturing wells was compared and analyzed. The results show that: Nitrogen …

Hydrogeochemical Evolution Of No.15 Coal Seam And Limestone K2 In Southern Qinshui Basin, Li Zhongcheng, Wu Jianguang, Wang Jianzhong, Wu Xiang, Lu Guojun

Coal Geology & Exploration

Based on the water test data of No.15 coal roof K₂ limestone and No.15 coalbed methane well in the southern Qinshui basin, the characteristics, types and the genetic mechanism of water chemical composition were systematically studied by statistical and comparative methods. The evolution model was built to systematically describe the various reactions and effects of limestone and coalbed water in the recharge zone, runoff zone and detention zone. The results show that the K₂ limestone water and the No.15 coal seam water will undergo ion exchange, mixing and CO₂ action. The K₂ limestone water is mainly …

Effect Of Acidification On The Microstructure And Physical Properties Of Shale, Chen Liuyu, Li Xijian, Shen Zhonghui, Xu Shiqing, Ma Shengxiang, Yin Xin

Coal Geology & Exploration

As the main shale gas reservoir in Guizhou, it is proved that Longmaxi Formation has good shale gas accumulation conditions and resource development potential. In order to reveal the response law of acidification on the micropore structure and physical properties of Longmaxi Formation shale in Guizhou, the difference in physical properties of shale microstructures before and after acidification, such as pore volume, porosity, specific surface area and pore size distribution was quantitatively characterized by X-ray diffraction(XRD) analysis, mercury intrusion measurement, low-temperature nitrogen adsorption and nuclear magnetic resonance(NMR) experiment. The structural characteristics of the shale pores before and after acidification were …

Common Midpoint Gather Constraint-Based Impedance Inversion Of Ground Penetrating Radar, Dai Qianwei, Ning Xiaobin, Zhang Bin

Coal Geology & Exploration

GPR impedance inversion is an effective method to obtain accurately the intrinsic parameters of the subsurface medium. This method relies on low frequency information provided by logging data, but it is rarely accompanied by drilling in practical applications. To solve the problem, the common midpoint velocity analysis is employed to provide more low frequency component information for impedance inversion of GPR to finely reconstruct the dielectric parameter of subsurface in the framework of velocity-constrained inversion technique. Firstly, a layer model is specifically set up as an example to verify the feasibility of the developed velocity- constrained inversion to regulate the …

Flow Simulation Considering Adsorption Boundary Layer Based On Digital Rock And Finite Element Method, Yong Fei Yang, Ke Wang, Qian Fei Lv, Roohollah Askari, Qing Yan Mei, Jun Yao, Jie Xin Hou, Kai Zhang, Ai Fen Li, Chen Chen Wang

Michigan Tech Publications, Part 1

Due to the low permeability of tight reservoirs, throats play a significant role in controlling fluid flow. Although many studies have been conducted to investigate fluid flow in throats in the microscale domain, comparatively fewer works have been devoted to study the effect of adsorption boundary layer (ABL) in throats based on the digital rock method. By considering an ABL, we investigate its effects on fluid flow. We build digital rock model based on computed tomography technology. Then, microscopic pore structures are extracted with watershed segmentation and pore geometries are meshed through Delaunay triangulation approach. Finally, using the meshed digital …

Remote Sensing And Three-Dimensional Photogrammetric Analysis Of Glaciofluvial Sand And Gravel Deposits For Aggregate Resource Assessment In Mchenry County, Illinois, Usa, Xiaodong Miao, Christopher J. Stohr, Paul R. Hanson, Qiansuo Wang

School of Natural Resources: Faculty Publications

Sand and gravel deposits, one of the most common natural resources, are used as aggregates mostly by the construction industry, and their extraction contributes significantly to a region's economy. Thus, it is critical to locate sand and gravel deposits, and evaluate their quantity and quality safely and quickly. However, information on aggregate resources is generally only available from conventional two-dimensional (2-D) geologic maps, and direct field measurements for quality analysis at outcrops are time consuming and are often not possible due to safety concerns, or simply because exposures are too difficult to access. In this study, we presented a methodology …

Spectroscopic Measurements Of Dissolved O3, H2o2 And Oh Radicals In Double Cylindrical Dielectric Barrier Discharge Technology: Treatment Of Methylene Blue Dye Simulated Wastewater, Emile Salomon Massima Mouele, Jimoh O. Tijani, Milua Masikini, Ojo O. Fatoba, Chuks P. Eze, Chionydua T. Onwordi, Myo Tay Zar Myint, Htet Htet Kyaw, Jamal Al-Sabahi, Mohammed Al-Abri, Sergey Dobretsov, Katri Laatikainen, Leslie F. Petrik

Mining Engineering Faculty Research & Creative Works

Advanced oxidation technologies (AOTs) focusing on nonthermal plasma induced by dielectric barrier discharge are adequate sources of diverse reactive oxygen species (ROS) beneficial for water and wastewater treatment. In this study, indigo, peroxytitanyl sulphate and terephthalic acid methods were used to approximate the concentrations of O₃, H₂O₂ and OH produced in a double cylindrical dielectric barrier discharge (DCDBD) plasma configuration. The effect of pH and scavengers as well as the amount of chemical probes on the generation of oxidants was investigated. The efficiency of the DCDBD reactor was further evaluated using methylene blue (MB) as …

Prediction Of Flotation Efficiency Of Metal Sulfides Using An Original Hybrid Machine Learning Model, Rachel Cook, Keitumetse Cathrine Monyake, Muhammad Badar Hayat, Aditya Kumar, Lana Alagha

Materials Science and Engineering Faculty Research & Creative Works

Froth flotation process is extensively used for selective separation of base metal sulfides from uneconomic mineral resources. Reliable prediction of process outcomes (metal recovery and grade) is vital to ensure peak performance. This work employs an innovative hybrid machine learning (ML) model—constructed by combining the random forest model and the firefly algorithm—to predict froth flotation efficiency of galena and chalcopyrite in relation to various experimental process parameters. The hybrid model's prediction performance was rigorously evaluated and compared against four different standalone ML models. The outcomes of this study illustrate that the hybrid ML model has the prediction ability to process …

Leaching Kinetics Of Rare Earth Elements From Fire Clay Seam Coal, Xinbo Yang, Rick Q. Honaker

Mining Engineering Faculty Publications

Recovery of rare earth elements (REEs) from coal samples collected from the Fire Clay coal seam using diluted mineral acid solutions was investigated. The initial processing step was coal recovery using conventional froth flotation which concentrated the REEs in tailing material resulting in an upgrade to values around 700 ppm on a dry whole mass basis. Leaching experiments were performed on the flotation tailings material using a 1.2 M sulfuric acid solution adjusted to a temperature of 75 °C to study the extractability of REEs from coal material. The effect of particle size, leaching time, leaching temperature, and solid concentration …

Tri-State Mining District, Ecological System, And Human Health: Systematic Literature Review Analysis, Jihyun Jane Min

Posters

Objective: Although extensive research exists on corrosive environments in the Tri-State Mining District (TSMD), there has been a lack of research on how such harmful effects in the TSMD could affect residents living in those areas. However, quite recently, such research regarding relationships between the health conditions of low-income residents and toxic elements in TSDM began to grow. Therefore, the increase of empirical studies means greater complexity of the findings that require a more intricate understanding.

Methods: To meet the necessity of the study, this research was conducted by an extensive systematic review of the literature on the harmful effects …

Ato Mode-Based Modular Platform Development Of Variable Luffing Crawler Drilling Rig Used In Underground Coal Mine, Song Haitao, Yao Ningping, Yao Yafeng, Han Jian, Peng Tao

Coal Geology & Exploration

With the continuous popularization of customized crawler rigs in coal mines, the variety and specifications of crawler rigs have been further refined, diversified and complicated, and the modular platform of variable luffing crawler rigs has been successfully developed. The four key steps in the development of modular platform were analyzed: the construction of modular platform, the rational division and development of modular components, the integration and development of modular components, the modular customization model for customers based upon the proposed ATO-based model. The application results show that the establishment of the variable luffing crawler rig modular platform shortens respond to …

Development Situation And Prospect Of Luffing Mechanism Of Drilling Rig In Underground Coal Mine, Yao Yafeng, Yao Ningping, Peng Tao

Coal Geology & Exploration

The luffing mechanism of drilling rig is used to adjust the opening parameters of the borehole, that is, azimuth angle, inclination angle, and height. According to the structural differences of different types of drilling rig and the construction characteristics of borehole in underground coal mine, this paper summarizes the adjustment requirements to opening parameters and proposes the research goal, which can rapidly and accurately adjust the parameters of the borehole and safeguard the stability of drilling construction. It is concluded that the luffing mechanism of drilling rig in underground coal mine has overall characteristics of small size, large adjustment range …

Key Technology For Rapidly Drilling Large Diameter Destressing-Drillhole In Rockburst Coal Seam, Wei Hongchao, Wang Yi, Wang Bo

Coal Geology & Exploration

In order to improve the hole forming rate and construction efficiency of large diameter destressing-drillhole in rockburst mine, based on the analysis of the stress characteristics of coal rock in rockburst coal mine, the dynamic instability characteristics of destressing-drillhole and the construction features, the key points for drilling large diameter destressing-drillhole, the efficient discharge of cuttings and fast drilling/lifting were proposed. Combining with the discharge of cuttings method by dual-power, the technology and equipment for rapidly drilling large diameter destressing-drillhole in rockburst coal seam were formed finally after the design and optimization of key equipment, drilling tools, technology and drilling …

Foam Drilling Technology And Application For Broken Soft Coal Seam In Underground Coal Mine, Ji Qianhui, Dong Mengmeng, Liu Jianlin, Shi Lei

Coal Geology & Exploration

Aiming at the limitation of middle pressure air drilling for gas drainage in soft and broken coal seam, such as limited drill cutting removal capacity, and dust pollution, foam drilling technique research in underground coal mines was carried out. CFD simulation of the flow field during the drilling process was conducted to obtain the optimized drilling tool structure parameters for efficient drill cutting transportation. Optimal structural parameters of wide-blade milled auger drill rod with the number of heads 3, the groove width 26 mm, and the pitch 110 mm were determined. A foam perfusion system suitable for underground coal mining …

Development Of Small Diameter Hydraulic Agitator With Cable For Directional Drilling In Underground Coal Mine, Wang Li, Xu Baolong, Wang Yi, Huang Hanjing, Jia Mingqun, Ma Bin

Coal Geology & Exploration

Aiming at the problems of large drilling pressure, low drilling efficiency and limited hole depth caused by the backing effect of drill string during deep hole directional drilling in underground coal mine, the technical idea of using hydraulic agitator was proposed. The ø89 mm small diameter hydriculic agitator was designed based on valve principle, the exciting force, excitation frequency were identified, and the cabled sub was developed. The performance parameters of hydraulic agitator with disc spring and cylindrical spring were tested. The results show that when the flow rate of 300 L/min the disc spring hydraulic agitator has the maximum …

Distribution And Resource Prospect Of Metal Ore Spots(Deposits) In Coal Of Different Coal-Forming Ages In Northern China, Ning Shuzheng, Huang Shaoqing, Zhang Li, Huang Wenhui, Cao Daiyong, Yuan Jianjiang, Zhang Jianqiang, Zhu Shifei, Yan Deyu, Liu Kang

Coal Geology & Exploration

In some cases, metals such as germanium, gallium, lithium and rare earth elements can be enriched in coal, which is an important potential source of these metals. There are abundant coal resources in northern China, and a large number of coal-metal ore spots(deposits) have been found, and the distribution of these ore spots(deposits) shows certain temporal and spatial characteristics: Metals in Permo-Carboniferous coal occur mainly as gallium and lithium-enriched ore spots, mainly are distributed in the northern coalfields of North China coal bearing regions and mining areas such as Pingshuo and Jincheng in Shanxi Province; the metal enrichment in Early-Middle …