Mining Engineering Commons^™

Time Effect Of Water Injection On The Mechanical Properties Of Coal And Its Application In Rockburst Prevention In Mining, Xiaofei Liu, Guang Xu, Chong Zhang, Biao Kong, Jifa Qian, Dong Zhu, Mingyao Wei

Guang Xu

Coal seam water injection is widely used to prevent rockbursts in coal mines, and the duration of water injection is an important parameter related to the effectiveness of rockburst prevention, making it of practical importance to optimize the effective water injection duration. This paper presents the test results of the mechanical properties and pore structure of samples with different soaking time, obtained from a working face where rockburst occurred. Soaking time changes the mechanical properties of samples, and this time effect differs with the coal size (from centimeter to nanometer size). Results of numerical simulation and on-site tests in the ...

Study On The Effect Of Iron-Based Deoxidizing Inhibitors For Coal Spontaneous Combustion Prevention, Chaoyu Hao, Yanling Chen, Jiren Wang, Cunbao Deng, Guang Xu, Fengwei Dai, Rui Si, Hongfei Wang, Haoyu Wang

Guang Xu

To improve the prevention of spontaneous coal combustion, reduced iron powder and other ingredients should be added together to form an iron-based deoxidizing inhibitor, with the dual effect of oxygen consumption and inhibition. The oxygen consumption rate of the inhibitor was studied through experiments. According to the theory of coordination resistance, the coordination resistance of Fe³⁺ was studied via the density functional method. Subsequently, a comparative experiment of the effects on spontaneous coal combustion was conducted. The research shows that several kinds of common resistance agents that are added to the reduced iron powder can consume oxygen. However, the ...

Study On Safety Control Of Composite Roof In Deep Roadway Based On Energy Balance Theory, Zhengzheng Xie, Nong Zhang, Yuxin Yuan, Guang Xu, Qun Wei

Guang Xu

Improving the safety and stability of composite roof in deep roadway is the strong guarantee for safe mining and sustainable development of coal mines. With three roadways of different composite roofs in Hulusu Coal Mine and Menkeqing Coal Mine as the research background, this paper explores the mechanical properties and energy dissipation law of coal-rock structures with different height ratios from the perspective of energy release and dissipation through lab experiments. The results indicate that the key to the stability of coal-rock structures lies in maintaining relatively low dissipation energy. Based on experimental results and the energy balance theory, two ...

Multi-Auv Cooperative Target Hunting Based On Improved Potential Field In A Surface-Water Environment, Hengqing Ge, Guibin Chen, Guang Xu

Guang Xu

In this paper, target hunting aims to detect target and surround the detected target in a surface-water using Multiple Autonomous Underwater Vehicles (multi-AUV) in a given area. The main challenge in multi-AUV target hunting is the design of AUV's motion path and coordination mechanism. To conduct the cooperative target hunting by multi-AUV in a surface-water environment, an integrated algorithm based on improved potential field (IPF) is proposed. First, a potential field function is established according to the information of the surface-water environment. Then, the dispersion degree, the homodromous degree, and district-difference degree are introduced to increase the cooperation of ...

Focus Energy Determination Of Mining Microseisms Using Residual Seismic Wave Attenuation In Deep Coal Mining, Mingwei Zhang, Shengdong Liu, Shuzhao Chen, Yanlong Chen, Guang Xu, Deyu Qian

Guang Xu

Based on the energy attenuation characteristics of residual wave in deep rock, a method was developed to determine the microseismic focus energy. Differential energy loss in infinitesimal spreading distance is logically deduced, upon which energy attenuation equation was established. With a logarithmic transformation, a linear relation of the residual seismic energy with distance is formulated. Its intercept was used to determine the microseismic focus energy. The result is compared with that determined by the energy density method. The reliability of the determined focus energy and the impact of the built-in velocity threshold on the residual wave energy computation are discussed ...

Impact Of Coalbed Incidence Angle On Methane Enrichment Zone In Longwall Gob, Shengyong Hu, Ao Zhang, Guorui Feng, Shuwen Guan, Xiangqian Guo, Chao Li, Guang Xu

Guang Xu

To control methane emissions in gob into longwall working faces, it is necessary to understand the distributions of methane enrichment zones (MEZ) around mined coal seams with different incidence angles. In this paper, FLAC^3D software is used to calculate the three-dimensional stress distributions in MEZ in gobs with coalbed incidence angles ranging from 0° to 50°. The results show that MEZ consistently exhibit a "hexagon" shape, and rotate in a clockwise direction as the coalbed angle increases. The MEZ range above the mined seam is larger than that below the mined seam. As the coalbed angle increases, the MEZ ...

Effects Of Loading Rate On Gas Seepage And Temperature In Coal And Its Potential For Coal-Gas Disaster Early-Warning, Chong Zhang, Xiaofei Liu, Guang Xu, Xiaoran Wang

Guang Xu

The seepage velocity and temperature externally manifest the changing structure, gas desorption and energy release that occurs in coal containing gas failure under loading. By using the system of coal containing gas failure under loading, this paper studies the law of seepage velocity and temperature under different loading rates and at 1.0 MPa confining pressure and 0.5 MPa gas pressure, and combined the on-site results of gas pressure and temperature. The results show that the stress directly affects the seepage velocity and temperature of coal containing gas, and the pressure and content of gas have the most sensitivity ...

Calibration Of Mine Ventilation Network Models Using The Non-Linear Optimization Algorithm, Guang Xu, Jinxin Huang, Baisheng Nie, Duncan Chalmers, Zhuoming Yang

Guang Xu

Effective ventilation planning is vital to underground mining. To ensure stable operation of the ventilation system and to avoid airflow disorder, mine ventilation network (MVN) models have been widely used in simulating and optimizing the mine ventilation system. However, one of the challenges for MVN model simulation is that the simulated airflow distribution results do not match the measured data. To solve this problem, a simple and effective calibration method is proposed based on the non-linear optimization algorithm. The calibrated model not only makes simulated airflow distribution results in accordance with the on-site measured data, but also controls the errors ...

A Mine Main Fans Switchover System With Lower Air Flow Volatility Based On Improved Particle Swarm Optimization Algorithm, Hengqing Ge, Guang Xu, Jinxin Huang, Xiaoping Ma

Guang Xu

A reliable ventilation system is essential for maintaining a comfortable working environment and ensuring safety production in an underground coal mine. The automated fan switchover technique was developed for changing the main fan for maintenance with lower air flow volatility of underground mine in the switchover process. This article established the optimization model in the main fans switchover process, used the improved particle swarm optimization algorithm to solve the model, and achieved minimum air flow volatility in the fans switchover process. Compared to previous studies, computer simulations have shown that the proposed algorithm can effectively find the global optimal solution ...

Study On Safety Control Of Composite Roof In Deep Roadway Based On Energy Balance Theory, Zhengzheng Xie, Nong Zhang, Yuxin Yuan, Guang Xu, Qun Wei

Mining and Nuclear Engineering Faculty Research & Creative Works

Improving the safety and stability of composite roof in deep roadway is the strong guarantee for safe mining and sustainable development of coal mines. With three roadways of different composite roofs in Hulusu Coal Mine and Menkeqing Coal Mine as the research background, this paper explores the mechanical properties and energy dissipation law of coal-rock structures with different height ratios from the perspective of energy release and dissipation through lab experiments. The results indicate that the key to the stability of coal-rock structures lies in maintaining relatively low dissipation energy. Based on experimental results and the energy balance theory, two ...

Investigation Of Properties Alternation During Super-Critical Co2 Injection In Shale, Sai Wang, Kouqi Liu, Juan Han, Kegang Ling, Hongsheng Wang, Bao Jia

Petroleum Engineering Faculty Publications

The low recovery of oil from tight liquid-rich formations is still a major challenge for a tight reservoir. Thus, supercritical CO2 flooding was proposed as an immense potential recovery method for production improvement. While up to date, there have been few studies to account for the formation properties' variation during the CO2 Enhanced Oil Recovery (EOR) process, especially investigation at the micro-scale. This work conducted a series of measurements to evaluate the rock mechanical change, mineral alteration and the pore structure properties' variation through the supercritical CO2 (Sc-CO2) injection process. Corresponding to the time variation (0 days, 10 days, 20 ...

A Numerical Model Of The Subaerial Landslide Generated Waves Of The Berkeley Pit, Matthew Mchugh

Mathematics, Engineering and Computer Science Undergraduate Theses

Southwestern Montana has a very rich history because of its mining activities. Butte, home to the richest hill on earth, is no exception. Underground operations resulted in 10,000 miles of horizontal underground workings [1]. In 1950s the mining methods converted from underground to surface open-pit mining with the opening of the Berkeley Pit. In 1982 the pumps shut down and the Pit began receiving groundwater discharge. Slope instabilities along the Pit0s slopes result in occasional soil sloughs; in some instances, the sloughing generates a large enough volume of soil to propagate a wave across the Pit Lake. This is ...

Wall Control Blasting At The Orphan Boy Mine – Butte, Montana, Jewel Sakyi

Graduate Theses & Non-Theses

Blasting is often conducted to produce desirable fragment sizes to minimize production cost and energy consumption in downstream processes, including loading, hauling, and crushing. However, the venting of explosive energy in the rock formation sometimes causes unwanted damage beyond the desired perimeter of the blast area. Control blasting has mainly been used in surface mining operations to minimalize blast damage. To explore the applicability of control blasting in underground mining operations, protect the safety of students, faculty, and staff, prevent overbreak, and to ensure the stability of openings and workings, four experimental control blasts, comprising of three smooth blasts and ...

Developing Trees Tolerant To Degraded Mine Soils, Francis Inkoom

Graduate Theses & Non-Theses

The project discussed in this thesis is part of a larger project developing trees that can tolerate and withstand heavy metals and acidic soils from historic mining operations in Butte Montana as a solution to re-establishing long-term tree growth on those sites. The project involved growing tree seedlings native to Butte, Montana and planting them on degraded mine soils, tailings, and processing wastes (mine waste) located within the Butte Priority Soil Operable Unit (BPSOU). The seedlings were grown for 34 weeks in a greenhouse located on Montana Tech’s campus before being transplanted to a contaminated site (the Clark Mill ...

Corporate Social Responsibility: Understanding The Mining Stakeholder With A Case Study, Sisi Que, Liang Wang, Kwame Awuah-Offei, Wei Yang, Hui Jiang

Mining and Nuclear Engineering Faculty Research & Creative Works

The social responsibility of corporate mining has been challenged by a significant socio-political risk from local communities. These issues reduce shareholder value by increasing costs and decreasing the market perception of corporate social responsibility. Community engagement is the process of understanding the behavior and interests of a group of targeted mining communities through surveys and data analysis, with the purpose of incorporating mining community acceptance into the mining sustainability. While mining organizations have discussed community engagement to varying degrees, there are three main shortcomings in current studies, as concluded in the authors' previous research. This paper presents a framework to ...

A Mine Main Fans Switchover System With Lower Air Flow Volatility Based On Improved Particle Swarm Optimization Algorithm, Hengqing Ge, Guang Xu, Jinxin Huang, Xiaoping Ma

Mining and Nuclear Engineering Faculty Research & Creative Works

A reliable ventilation system is essential for maintaining a comfortable working environment and ensuring safety production in an underground coal mine. The automated fan switchover technique was developed for changing the main fan for maintenance with lower air flow volatility of underground mine in the switchover process. This article established the optimization model in the main fans switchover process, used the improved particle swarm optimization algorithm to solve the model, and achieved minimum air flow volatility in the fans switchover process. Compared to previous studies, computer simulations have shown that the proposed algorithm can effectively find the global optimal solution ...

Explosive Dust Test Vessel Comparison Using Pulverized Pittsburgh Coal, Jacob Miller, Jay Schafler, Phillip R. Mulligan, Robert Eades, Kyle A. Perry, Catherine E. Johnson

Phillip R. Mulligan

Explosions of coal dust are a major safety concern within the coal mining industry. The explosion and subsequent fires caused by coal dust can result in significant property damage, loss of life in underground coal mines and damage to coal processing facilities. The United States Bureau of Mines conducted research on coal dust explosions until 1996 when it was dissolved. In the following years, the American Society for Testing and Materials (ASTM) developed a test standard, ASTM E1226, to provide a standard test method characterizing the “explosibility” of particulate solids of combustible materials suspended in air. The research presented herein ...

Cryptocurrency Mining On Mobile As An Alternative Monetization Approach, Nguyen Phan Sinh Huynh, Kenny Choo, Rajesh Krishna Balan, Youngki Lee

Research Collection School Of Information Systems

Can cryptocurrency mining (crypto-mining) be a practical ad-free monetization approach for mobile app developers? We conducted a lab experiment and a user study with 228 real Android users to investigate different aspects of mobile crypto-mining. In particular, we show that mobile devices have computational resources to spare and that these can be utilized for crypto-mining with minimal impact on the mobile user experience. We also examined the profitability of mobile crypto-mining and its stability as compared to mobile advertising. In many cases, the profit of mining can exceed mobile advertising's. Most importantly, our study shows that the majority (72 ...

Landslides Near Enguri Dam (Caucasus, Georgia) And Possible Seismotectonic Effects, Alessandro Tibaldi, Paolo Oppizzi, John S. Gierke, Thomas Oommen, Nino Tsereteli, Zurab Gogoladze

Department of Geological and Mining Engineering and Sciences Publications

The Enguri dam and water reservoir, nested in the southwestern Caucasus (Republic of Georgia), are surrounded by steep mountain slopes. At a distance of 2.5 km from the dam, a mountain ridge along the reservoir is affected by active deformations with a double vergence. The western slope, directly facing the reservoir, has deformations that affect a subaerial area of 1.2 km². The head scarp affects the Jvari–Khaishi–Mestia main road with offsets of man-made features that indicate slip rates of 2–9 cm yr⁻¹. Static, pseudostatic and Newmark analyses, based on field and seismological data ...

Assessment Of Post-Wildfire Debris Flow Occurrence Using Classifier Tree, Priscilla Addison, Thomas Oommen, Qiuying Sha

Department of Geological and Mining Engineering and Sciences Publications

Besides the dangers of an actively burning wildfire, a plethora of other hazardous consequences can occur afterwards. Debris flows are among the most hazardous of these, being known to cause fatalities and extensive damage to infrastructure. Although debris flows are not exclusive to fire affected areas, a wildfire can increase a location’s susceptibility by stripping its protective covers like vegetation and introducing destabilizing factors such as ash filling soil pores to increase runoff potential. Due to the associated dangers, researchers are developing statistical models to isolate susceptible locations. Existing models predominantly employ the logistic regression algorithm; however, previous studies ...

Predictive Modeling Of Dc Arc Flash In 125 Volt System, Austin Cody Gaunce

Theses and Dissertations--Mining Engineering

Arc flash is one of the two primary hazards encountered by workers near electrical equipment. Most applications where arc flash may be encountered are alternating current (AC) electrical systems. However, direct current (DC) electrical systems are becoming increasingly prevalent with industries implementing more renewable energy sources and energy storage devices. Little research has been performed with respect to arc flash hazards posed by DC electrical systems, particularly energy storage devices. Furthermore, current standards for performing arc flash calculations do not provide sufficient guidance when working in DC applications. IEEE 1584-2002 does not provide recommendations for DC electrical systems. NFPA 70E ...

Investigation Of Long Term Pillar Stability In An Abandoned Gypsum Mine Based On Dissolution Models, Mohammadhossein Sadeghiamirshahidi

Dissertations, Master's Theses and Master's Reports

The abandoned Domtar Mine in Grand Rapids, MI underlies Interstate I-196. The mine operated for over 140 years, mining a 30-meter-deep, four-meter thick gypsum seam. In 2000, the mine was abandoned with the removal of the mine’s dewatering pumps allowing groundwater to flood the mine. The initial flooding resulted in saturating the mine pillars along with some amount of pillar dissolution. Overtime, gypsum dissolution would cease as the water becomes saturated with the gypsum dissolution products. The mine, however, is located adjacent to the Grand River and has groundwater moving through the mine resulting in the potential for continuing ...

Feed Control: Composite Recycle, Rosy Perez

All Undergraduate Projects

The Boeing Company gave Central Washington University an opportunity for students to research and come up with an idea to reduce costs and landfill waste caused by the trimmings from the 777x composite wing pieces. The engineering and manufacturing for this project is about transporting composite material through to the delamination and chipper process. The delamination process uses a ram to press two claw shaped devices together that bends and deforms the material in opposite directions. The chipper process uses counter rotating saw blades spaced 1/8” apart to produce small shredded material. It is important for this newly designed ...

Improving Base Metal Electrowinning, Charles Ebenezer Abbey

Doctoral Dissertations

"In zinc electrowinning, Mn oxidizes to form MnO₂ on Pb-Ag anodes, cell walls and pipes. MnO₂ reduces anode corrosion but also leads to short circuits and maintenance issues. MnO₂ is thought to interact with chloride ions and produce oxidized chlorine species. The interactions between Mn and Cl are not well understood. Bench scale experiments were conducted to investigate the effects of the manganese to chloride ratio on anode corrosion rate and electrolyte chemistry using rolled Pb-Ag anodes. Increasing the average Mn/Cl^- ratio from ~7:1 to ~11:1 reduced the anode corrosion rate. Anode scales produced ...

Investigating Blast Fume Propagation, Concentration And Clearance In Underground Mines Using Computational Fluid Dynamics (Cfd), Raymond Ninnang Tiile

Doctoral Dissertations

"Blasting activities using standard industry explosives is an essential component of underground hard rock mining operations. Blasting operations result in the release of noxious gases, presenting both safety and productivity threats. Overestimation of post-blast re-entry time results in production losses, while underestimation leads to injuries and fatalities. Research shows that most underground mines simply standardize post-blast re-entry times based on experiences and observations. Few underground mines use theoretical methods for calculating post-blast re-entry time. These theoretical methods, however, are unable to account for the variations in the blasting conditions. Literature review shows that: (i) there is currently no means of ...

Pressure Versus Impulse Graph For Blast-Induced Traumatic Brain Injury And Correlation To Observable Blast Injuries, Barbara Rutter

Doctoral Dissertations

"With the increased use of explosive devices in combat, blast induced traumatic brain injury (bTBI) has become one of the signature wounds in current conflicts. Animal studies have been conducted to understand the mechanisms in the brain and a pressure versus time graph has been produced. However, the role of impulse in bTBIs has not been thoroughly investigated for animals or human beings.

This research proposes a new method of presenting bTBI data by using a pressure versus impulse (P-I) graph. P-I graphs have been found useful in presenting lung lethality regions and building damage thresholds. To present the animal ...

Removal Of Antimony And Bismuth From Copper Electrorefining Electrolyte By Two Proprietary Solvent Extraction Extractants, Andrew Artzer

Masters Theses

"Antimony and bismuth are two of the most problematic impurities in copper electrorefining (ER). Because of this, much research has been done investigating the ways to remove them. Processes that are currently being used industrially include anode additions, liberators, ion exchange (IX), and solvent extraction (SX). Of these, liberators and anode additions are the most common while SX is the least, mostly being used for arsenic removal. There are other methods that have been evaluated, but are not in commercial use. These include the use of various electrolyte additives, and adsorbents such as bentonite clay and heavy metal sulfates.

Two ...

Leaching Characteristics Of Rare Earth Elements From Bituminous Coal-Based Sources, Xinbo Yang

Theses and Dissertations--Mining Engineering

The demand for rare earth elements (REEs) has increased over the last decade due to applications in high technology devices including those in the defense industry. The recovery of REEs from primary sources such as rare earth minerals are viable using physical separations followed by chemical processing. However, weak market values and environmental concerns have limited the viability of such operations. On the other hand, REE recovery from secondary sources such as apatite ore, bauxite waste, and waste recycling, provides an opportunity to take advantage of a resource that does not require mining costs as well as other associated costs ...

Simplifying Techniques Applied To Computational Fluid Dynamics Modeling Of Methane Explosions, Laura Steeves

Theses and Dissertations--Mining Engineering

Traditional methods of studying underground coal mine explosions are limited to observations and data collected during experimental explosions. These experiments are expensive, time-consuming, and require major facilities, such as the Lake Lynn Experimental Mine. The development of computational fluid dynamics (CFD) modeling of explosions can help minimize the need for large-scale testing. This thesis utilized the commercial CFD software, SC/Tetra, to examine three case studies. The first case study modeled the combustion of methane in a scaled shock tube, measuring approximately 1 foot by 1 foot, by 20.5 feet long, with a methane cloud of 2.5 feet ...

The Redesigned Vortecone: A Maintenance-Free Wet Scrubber Device, Allison Taylor

Theses and Dissertations--Mining Engineering

Dust creates health and safety issues in mining and there are several different ways to reduce the amount of respirable dust created. Dust particles also affect the operation and efficiency of mining equipment. One device currently used to reduce dust in a coal mine is a flooded-bed dust scrubber. These type of scrubbers are found on continuous miners and are designed to capture dust particles close to the cutting head. However, the fibrous screens on the flooded-bed dust scrubber clog easily reducing both production and the quality and quantity of air miners are exposed too. The flooded-bed dust scrubber was ...