Engineering Commons^™

Development And Application Of A Supercritical Co2 Pulsed Fracturing-Seepage Coupling Test System, Liu Jiajia, Zhang Yunlong, Nie Zishuo, Gao Zhiyang, Xu Wensong

Coal Geology & Exploration

[Objective] To effectively enhance the extraction effects of coalbed methane (CBM), this study proposed a novel approach for fracturing coals (rocks) using pulsation of supercritical carbon dioxide (CO₂) by combining pulsed fracturing with supercritical CO₂ fracturing. [Methods] A true triaxial test system coupling supercritical CO₂ pulsed fracturing with seepage was independently developed, and its primary structure, characteristics, and functions were elucidated. Then, the supercritical CO₂ pulsed fracturing - seepage/acoustic emission monitoring tests under true triaxial conditions were conducted in the laboratory. The test system, controlling the triaxial stress by combining an independent servo system with …

Remote Sensing Monitoring And Spatiotemporal Characteristics Of Co2 And Ch4 Concentrations In Coal-Electricity Production Bases, Xu Yanfei, Chen Yongchun, Li Jing, Liu Xiaozhou, Miao Wei, Zhao Derong, Rui Chengqi

Coal Geology & Exploration

[Objective] CO₂ and CH₄ are identified as the primary greenhouse gases emitted from energy production in coal-electricity production bases. Mointoring these emissions and analyzing their spatiotemporal distribution are essential components of building a carbon monitoring system in the study area. [Methods] This study investigated Huainan City, Anhui Province as an example to explore the spatiotemporal characteristics of CO₂ and CH₄ in coal-electricity production bases. Specifically, this study examined the CO₂ and CH₄ concentrations in the study area based on data from the GOSAT，OCO-2, and Sentinel-5P satellites，determining the column concentration changes and distribution of CO …

Investigation And Comprehensive Utilization Of Resources In Closed Coal Mines In Anhui Province, China, Liu Feiyue, Chen Wanyun, Yang Ke, Duan Minke, Liu Qinjie, Yang Lingyue

Coal Geology & Exploration

[Objevtive] With the continuously intensive exploitation of coal resources and the structural reform of energy supply, many coal mines in Anhui Province have been closed due to resource depletion or backward production capacity. However, the closed coal mines still host resources such as underground spaces, residual coals, gas, mine water, land, and infrastructure equipment. Hence, reutilizing resources in closed coal mines holds significant engineering value and economic benefits. [Methods] Based on the general information and reutilization status of 59 coal mines in Anhui Province that have been closed since 2013, this study analyzed the distribution characteristics, residual resources, and reutilization …

Physical Simulation Experiments On Mining-Induced Water Inrushes From Coal Seam Floors: Advances In Research And Prospects, Zhang Pingsong, Ou Yuanchao

Coal Geology & Exploration

[Objective] Water inrushes from floors are subjected to the superimposed effects of factors such as specific geological structures, water-rock-stress coupling, and mining disturbance, proving complex, concealed, and abrupt. [Methods] Physical simulation experiments can effectively reproduce the environments of the floors and confined water, intuitively present the whole process of both mining-induced fracture propagation in the floors and the path evolution of water inrushes, and obtain multi-source data of all disaster stages in a real time manner. Therefore, such experiments enjoy unique advantages in investigating water inrushes from floors. [Results and Conclusions] This study reviews the research achievements in water inrushes …

A High-Resolution Method For Processing Coal Measures Seismic Data Based On Anisotropic Medium Theories And Its Application, Li Huiting, Chang Suoliang, Zhang Sheng, Guan Wenyuan, Zhao Xing, Wang Weiqian, Tantai Mingjun, Gao Kaixin

Coal Geology & Exploration

[Objective] The increasing importance of the exploration and exploitation of deep resources poses new requirements for high-precision seismic exploration. Given that conventional isotropy-based data processing methods are no longer applicable to the coal-bearing strata with strong anisotropy. [Methods] This study proposed a method for processing seismic data based on theories of both transverse isotropy medium with a vertical symmetry axis (VTI) media and transverse isotropy with a horizontal axis of symmetry (HTI) media. First, to characterize the depositional characteristics of coal-bearing strata, this study analyzed the features of VTI media, revealing that high-order dynamic correction can effectively eliminate anisotropy-induced event …

Investigation Of The Use Of Recycled Concrete Aggregates In Porous Asphalt Mixture, Asad Elmagarhe

USF Tampa Graduate Theses and Dissertations

This study aims to address the national need for using recycled concrete in road pavements. This is especially important in the governmental and corporate sectors, where reducing the cost and carbon footprint of construction projects is a priority. The long-term goal is to meet the public demand for environmentally friendly infrastructure and minimize the harmful effects of waste disposal on humans and the environment.

The project focuses on using recycled concrete aggregate (RCA) in porous asphalt pavement to reduce stormwater runoff, a popular environmentally friendly road design. However, compared to regular dense asphalt mixtures, porous asphalt mixtures (PAM) are more …

Modified Method For Assessing The Required Expenditures And Estimated Time Of Hard Coal Mine Liquidation, Andrzej Chmiela, Małgorzata Wysocka, Adam Smoliński

Journal of Sustainable Mining

The restructuring of hard coal mining requires significant budgetary expenditures. A comprehensive scientific approach may facilitate the rationalisation and minimisation of mine closure costs. This study proposes a method for the preliminary estimation of the costs and time required for the potential liquidation of a hard coal mine. In addition to a literature review, a statistical analysis and a case study, personal interviews were conducted with individuals with direct management over the restructuring, reclamation and liquidation processes pertaining to mines undergoing closure.

The assessment method is based on an analysis of the mine liquidation costs, divided into successive years of …

Study On Law And Influencing Factors Of Air Leakage In Isolated Island Working Face With Large Burial Depth, Gang Wang, Mingze Xia, Shuliang Xie, Hao Xu, Shuxin Wang, Xintai Deng

Journal of Sustainable Mining

During the mining of a single coal seam isolated island work surface with large burial depth, the high mine pressures can crush and break the protective coal pillars, causing serious air leakages in the rear goaf. Herein, we use the analytic hierarchy process(AHP) to determine the main influencing factors of air leakage in island mining face. The air leakage source and sink in goaf were determined by measuring the differential pressures between the island mining face and the adjacent goaf using the energy level measurement method. The air volumes in the roadways were monitored on site to quantitatively analyze the …

Gender-Based Service Quality Evaluation Of Multimodal Public Transportation In Dki Jakarta, Mohammad Owais, Jachrizal Sumabrata, Nahry Yusuf

Smart City

In DKI Jakarta, despite the extensive infrastructure development, there has been a significant decline in the usage of public transportation. This can be attributed to the inadequate quality of the services provided. Various studies have highlighted the significance of evaluating the quality of service in public transportation to ensure passenger satisfaction and attract new users. However, there is no agreement on the most effective methodology and suitable indicators for conducting such analyses. In addition, there is a growing recognition of the importance of promoting gender equality in multimodal public transportation (MMPT) and understanding gender differences and perceptions of MMPT services. …

Prototype Device For Measuring The Dustiness Of Stone And Lime Dust Used In Explosion Prevention, Adrian Toman, Zdzisław Dyduch, Tomasz Skowronek

Journal of Sustainable Mining

This paper presents the prototype of a device for measuring the dustiness of powdered materials by means of a new measurement method. The currently employed stationary laboratory device, utilised in KD “Barbara”, uses the attenuation of a radiant flux transmitted through a dust cloud induced by a manually generated air blast. The new device uses the same measurement method, but it includes modern elements based on a microprocessor, a laser line generator instead of an LED diode, and a precise multi-channel detector. The generated quantity of the mixture (dust and air) is strictly determined and precisely dosed via buffer containers, …

Tracking Mining Company Electric Vehicles For Sustainable Development Optimization Using Distributed Ledger Technologies, Teodora Hristova

Journal of Sustainable Mining

It is established that based on the industrial revolutions towards Industry 5.0, the population of the Earth and its well-being are increasing. To preserve and improve living conditions the development in all spheres of life is by the paradigm of sustainable development. Through the prism of the mining industry, one step could be the introduction of circular economy measures for digitized tracking of materials, repairs, consumed electricity, safety, and finances. Implementing of electric cars is an option to achieve this goal through automation, manageability, and data traceability via Industry 4.0 technologies. Such are blockchain technologies, IoT, V2V, and others. For …

A Screening Life Cycle Analysis Of One-Way And Reusable Crate Designs – Estimating Environmental Impacts Via Lca Software, Nicolas R. Corona

Master's Theses

A comparison analysis conducted via COMPASS life cycle analysis software has indicated that a one-way crate design, rather than a reusable crate design, is in fact the more environmentally friendly packaging system. These results can be interpreted differently, however, as the manufacturer of said crate designs must confirm what impact indicators they would like to reference as environmental goalposts. The conducted analysis provides insight into what the environmental impacts of each packaging system look like as packaging at all three system levels has been identified as a means of reducing environmental impacts globally. As such, the manufacturer of said crate …

Cost Modeling Of Provision C.3 Green Stormwater Infrastructure Requirements For Residential Development In Concord, California, James Henry Mizutani

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

To assist the city of Concord in achieving its housing goals as presented in its general plan, while still meeting the stormwater discharge requirements laid out in the city’s municipal discharge permit, I worked with local developers and consultants to create a spreadsheet modeling tool that allows housing developers to estimate the total cost of green stormwater infrastructure needed to comply with local regulations.

This report contains a summary of the conditions leading to the necessity of this tool, the steps the tool takes that go beyond existing models, a description of how the model operates, instructions on how to …

Understanding The Impact Of Microplastic Contamination On Soil Quality And Eco-Toxicological Risks In Horticulture: A Comprehensive Review, N. P. Gayathri, Geena Prasad, Vaishna Prabhakaran, Vishnu Priya

Research outputs 2022 to 2026

The horticulture sector, essential for global food production, confronts significant challenges with prevalent pollutants, mainly microplastics. The presence of microplastics in the food chain has induced physiological stress and a multifactorial food safety concern. The complexity of the problem, arising from intricate interactions among microplastics, organisms, and ecosystems, poses a substantial challenge to food safety, necessitating an immediate strategic perspective due to the associated risks to human health and eco-toxicology. Significant knowledge gaps persist regarding their impact on terrestrial ecosystems, especially in horticulture. This study addresses the urgent need to comprehend the implications of microplastics on soil health, eco-toxicological risks, …

A Molecular Dynamics Study On The Destruction Mechanism Of Per And Polyfluoroalkyl Substances Due To Ultrasound Technology, Bruno Bezerra De Souza

Dissertations

Per- and polyfluoroalkyl substances (PFAS) are a group of stable synthetic chemicals that are highly persistent and harmful pollutants to the environment and human health. PFAS have caused a strong public and regulatory response due to their ubiquitous presence in the environment and toxicity to humans. The application of ultrasound is one of the most effective treatment technologies for the mineralization of PFAS in contaminated water. However, this technology is treated as a black box causing the inability to be optimized. Therefore, there is a pressing need to investigate the intricate dynamics of PFAS degradation under ultrasound to unlock its …

Development Of Super Hydrophobic Membranes And Their Applications, Sumona Paul

Dissertations

Effective liquid phase separation is vital across industries, especially in aviation, chemicals, fuels, and textiles. Membrane technology offers advantages over traditional methods like distillation, with low energy consumption and protection for heat-sensitive molecules. Membrane performance is assessed based on factors such as materials, surface modification, and interactions. This research targets superhydrophobic membranes for liquid-liquid filtration and antiwetting omniphobic membranes for membrane distillation, focusing on properties like contact angle and thermal resistance.

This study presents a highly hydrophobic membrane achieved by immobilizing carbon nanotubes (CNTs) onto a PTFE microfiltration membrane. It's designed for dewatering organic-water mixtures with trace water content via …

Development Of The Nebraska Department Of Transportation Winter Severity Index – Phase Ii, Mark Anderson, Curtis L. Walker, Thomas Kauzlarich

Nebraska Department of Transportation: Research Reports

For the Nebraska Department of Transportation (NDOT), the Nebraska Winter Severity Index (NEWINS) provided an independent framework to calculate a winter season’s severity by categorizing individual winter storms. However, one of the greatest limitations of NEWINS is that it is not predictive. Thus, this study builds on the previously developed NEWINS by creating a predictive winter storm severity index known as NEWINS-Predictive (NEWINS-P). The quantitative precipitation forecast, snow accumulation, ice accumulation, and surface wind speed parameters from the National Digital Forecast Database (NDFD) are used to develop the five components composing the NEWINS-P framework. These components consist of snow severity …

Double Acting Liberation Of Ni And Co In The Pre-Treatment Process To Increase Recovery Of Nickel From Low-Grade Nickel Laterite, Eni Febriana, Muhamad Irham Mulyadi, Wahyu Mayangsari, Januar Irawan, Iwan Setiawan, Ahmad Maksum, Florentinus Firdiyono, Soesaptri Oediyani, Agus Budi Prasetyo, Johny W. Soedarsono

Journal of Sustainable Mining

This study highlights the effectiveness of employing double-acting liberation to release Ni and Co from the complex phases of the low-grade nickel laterite. It includes the addition of concentrated sulphuric acid and NaF as well as the heat treatment prior to roasting and leaching processes to improve the destruction of the complex phases contained. The finding describes that dehydration of iron sulfate and decomposition of the lizardite at a lower temperature, 270°C, were occurred in the pre-treatment process, followed by hematite formation in the roasting process. It subsequently accelerated Ni and Co extraction in the pregnant solution and omitted Fe …

Synthesis Of Geopolymer Using Coal Fly Ash And Corn Stover, Anu Paneru

Master's Theses

The development of each nation is dependent on its infrastructure, and nations are competing with others in infrastructure, especially in the construction of roadways, since they play a vital role in the economic and social development of the nation. The conventional materials used for road construction are cement and asphalt, which pose significant environmental challenges. This thesis explores the potential of fly ash (FA) and corn stover (CS) in synthesizing geopolymer, as an alternative material for the construction of roads. The study examines the impact of FA and CS percentages and the particle sizes of CS on the compressive strength, …

Dynamic Simulations And Applicability Evaluation Of Novel Perforation Techniques, Bi Gang, Yuan Peijie, Han Fei, Fu Shuaishuai, Wu Jiemin, Ma Ying

Coal Geology & Exploration

The development and improvement of perforated completion techniques hold great practical significance and value for efficient testing and exploitation of oil and gas fields. However, conventional shaped-charge perforation for well completion of low-permeability reservoirs (e.g., low-permeability coal seams) suffered high seepage resistance and reduced productivity due to the presence of compaction damage zones. To achieve enhanced exploitation efficiency of low-permeability reservoirs, novel perforation techniques, including self-cleaning and after-effect perforation, have been proposed. However, their perforation performance and applicability remain ambiguous. Based on the explicit time integration algorithm and fluid-structure interaction mechanism of LS-DYNA, this study proposed a method for finite …

A Simulation Study Of Mechanisms Behind Water Inrush From Fault-Bearing Floors Of Ultra-Thick Coal Seams Under Loading And Unloading At Significantly Variable Amplitude, Li Hao, Zhu Kaipeng, Guo Guoqiang, Zhou Yang, Kang Zhiqin

Coal Geology & Exploration

Ultra-thick coal seams feature large stope spaces and extensive disturbance ranges. Significantly variable amplitude loading and unloading are prone to cause the fault rupture of floors of ultra-thick coal seams, inducing water disasters. Numerical simulation serves as a critical method for revealing the fault reactivation and water inrush mechanisms at the floors of ultra-thick coal seams. The key of this method is to accurately inflect the coupling characteristics of rock mass rupture and fissure water under significantly variable amplitude loading and unloading. This study determined the correlations of the damage variable with plastic strain and stress, deriving the equations for …

Intelligent Identification Method Of Drilling Fluid Rheological Parameters Based On Machine Learning, Liu Changye, Yang Xianyu, Cai Jihua, Wang Ren, Wang Jianlong, Dai Fanfei, Guo Wanyang, Jiang Guoshe, Feng Yang

Coal Geology & Exploration

The rheology of drilling fluid, which characterizes its flow and deformation, is vital for transporting and suspending rock cuttings as well as for enhancing the drilling rate. Precise control of drilling fluid rheological parameters is essential to ensure borehole cleanliness and efficient drilling. This paper proposes an intelligent identification method for drilling fluid rheological parameters based on Convolutional Neural Networks (CNNs). The method employs magnetic stirring to generate stable images of drilling fluid flow, uses various data augmentation methods to increase the number of images and create a database, thereby enhancing the model’s robustness and generalization capabilities. The AlexNet CNN …

Dynamic Mechanisms Of Coal And Gas Outbursts Based On A Multi-Zone Combined Coal Model, Li Feng, Wang Chenchen, Wang Bo, Jing Yadong, Yan Zhengxu, Zhang Minbo

Coal Geology & Exploration

Coal and gas outbursts (hereafter referred to as outbursts) severely affect coal mining safety. However, many scientific problems underlying the outbursts remain unsolved. To minimize the influence of anisotropy in the mechanical properties of coals on research into outbursts, this study constructed a multi-zone combined coal model. Based on the stress distribution of overlying strata and the stress wave propagation mechanisms, this study located the weak zone of coals, shrinking the research object from the outburst center to the weak zone. Given that outbursts are triggered by the disturbance of external dynamic load, this study examined the propagation patterns of …

Geochemical Characteristics And Influencing Factors Of Deep Coalbed Methane In The Linxing-Shenfu Block, Wu Peng, Hu Weiqiang, Li Yangbing, Ma Litao, Li Yong, Zhao Fei, Niu Yanwei, Chen Jianqi, Li Panpan, Liu Zaizhen, Li Chenchen, Cao Di, Liu Cheng

Coal Geology & Exploration

Identifying the origin and geochemical characteristics of deep coalbed methane (CBM) is critical for its exploration and production. This study examined the desorbed gas from deep-CBM parameter wells in the Linxing-Shenfu block on the eastern margin of the Ordos Basin. It systematically tested the composition, content, and carbon isotopes of CBM in coal seams Nos. 8 and 9. In combination with the degree of thermal evolution, gas-bearing properties, coal seam burial depths, geological structures, and hydrogeologic conditions, it delved into the geochemical characteristics and influencing factors of deep CBM. The results show that the deep CBM in the study area …

Anti-Channeling Methods For Coalbed Methane Production Using L-Type Horizontal Wells, Liu Zhan, Zhang Qunxia, Geng Yuxin, Luo Dan, Wang Minggang

Coal Geology & Exploration

Coalbed methane (CBM) production using L-type horizontal wells can yield stable single-well production of up to above 8 000 m³/d. However, due to the lack of sand settling pockets, L-type horizontal wells fail to achieve gas-water separation under the action of gravity. Consequently, gas channeling from tubing is prone to occur, significantly decreasing pumping efficiency and restricting further drainage and pressure reduction. By optimizing the lifting process for production in the early stage, the gas channeling from tubing has been somewhat alleviated. However, the anti-channeling effects remain unsatisfactory in low-fluid-pressure and high-yield gas wells. This study examined L-type …

Technologies For Water Hazard Prevention And Control In Burnt Rock Aquifers Within Concealed Burnt Areas, Wang Hai

Coal Geology & Exploration

Burnt rocks are extensively distributed in northwestern China, featuring well-developed pores and fractures and abundant water, emerging as primary aquifers in this region. The burnt rocks in concealed burnt areas in this region show inconspicuous surface remains, complicating their identification. Penetrating burnt rock aquifers in coal mining will lead to water hazard and destroy water resources in these aquifers. To prevent and control water hazard in burnt rocks within concealed burnt areas and preserve water resources in burnt rock aquifers, this study analyzed the distributions of burnt rocks in China and the effects of water in them on coal mining. …

Development Of Remote Control System For Automatic Drilling Rig Used In Coal Mine, Dong Hongbo, Yao Ningping, Wang Tianlong, Ma Bin, Peng Guangyu

Coal Geology & Exploration

In response to the problems of high labor intensity and great safety risk of drilling rig under the complex construction environment, a set of remote monitoring system for automatic drilling rig of coal mine was developed using the electronic circuit, measurement sensing, remote control, video monitoring and big data technologies. The system, based on ZDY4500LFK coal mine drilling rig, has implemented the three control modes: in-line-of-sight control, underground centralized control and ground remote monitoring. Besides, a cloud automatic drilling rig management and control platform was established. Specifically, the in-line-of-sight monitoring is used to realize the accurate operation of drilling rig …

Research On Digital Twin-Driven Tracking, Positioning And Collision Detection Method Of Excavating And Anchoring Equipment, Yang Wenjuan, Zhao Dian, Zhang Xuhui, Chen Xin, Zheng Xili, Liu Yanhui, Zhang Ran, Wan Jicheng

Coal Geology & Exploration

The automation of excavating and anchoring operation is critical for intelligent excavation of coal mine roadway. Aiming at the challenges of relative pose measurement and collision detection during the alternating operation of the current excavating and anchoring equipment, a digital twin-driven tracking, positioning and collision detection method was proposed. Firstly, in order to overcome the influence of low illumination, high dust and complex background interference in the underground excavating face, the multi-point infrared LED target is taken as the information source, the infrared LED feature point image is collected by industrial camera, the center of the spot is extracted using …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

A Preliminary Study Of Coalbed Methane Adsorption At Fractal Interfaces, Jin Yi, Li Yani, Song Huibo, Zhao Mengyu, Yang Yunhang, Chen Zenan

Coal Geology & Exploration

The adsorption and desorption mechanisms of coalbed methane (CBM) are foundational for revealing CBM accumulation mechanisms and achieving efficient CBM exploitation. Studies have indicated that coal reservoirs exhibit complex pore structures with fractal features, significantly influencing CBM adsorption at pore-solid interfaces. Based on a comparative analysis of several common adsorption models for gas-solid interfaces and a summary of their characteristics and applicable conditions, this study suggests that all these adsorption models still rely on the stationary assumption of adsorption selectivity for the description and application of CBM adsorption behavior at fractal interfaces while overlooking the scale invariance of the adsorption …