Engineering Commons^™

Strategic Value And Scientific Exploration Of In-Situ Pyrolysis Of Tar-Rich Coals, Wang Shuangming, Shi Qingmin, Sun Qiang, Cui Shidong, Kou Bingyang, Qiao Junwei, Geng Jishi, Zhang Lei, Tian Hua, Jiang Pengfei, Cai Yue, Liu Lang

Coal Geology & Exploration

Background Given China's significant demand shortfall of oil and gas, numerous constraints on oil and gas supply, an arduous task of green and low-carbon energy transition of coals, tar-rich coals, a type of coal resource integrating the properties of coal, oil, and gas, have great potential for increasing the oil and gas supply of the country. Advances Despite the successful engineering test conducted in Yulin, Shaanxi Province, in-situ pyrolysis of tar-rich coals remains in its exploratory stage. This technology holds great strategic value in two aspects: (1) It enables reduced demand shortfall of oil and gas in China to enhance …

Numerical Simulations Of The Evolutionary Patterns Of Multi-Physical Fields During The In-Situ Pyrolysis Of Tar-Rich Coals, Yang Fu, Cheng Xiangqiang, Li Mingjie, Wu Zhiqiang, Wei Jinjia, Cao Husheng

Coal Geology & Exploration

Objective The in-situ pyrolysis of tar-rich coals, an emerging technology for coal resource utilization characterized by cleanliness, high efficiency, and safety, is still in its initial development stage. This technology is greatly influenced by the evolutionary patterns of multi-physical fields and critical process parameters. Methods A numerical simulation model involving multi-physical fields was established by coupling fluid flow, heat transfer, and chemical reactions, and its reliability was verified by comparing the numerical simulation results with the pyrolysis experimental results of cylindrical coal samples. Based on the pilot test conditions, the impacts of permeability, heat-carrier flow rate, and fracture zone height …

Impacts Of The Caking Property Of Tar-Rich Coals On Their Pore Structure Evolution And Seepage During Pyrolysis, Chang Zhibing, Wang Chuchu, Kuang Wenhao, Tang Ying, Wu Xiaodan, Liu Shuqin

Coal Geology & Exploration

Objective The in-situ pyrolysis of tar-rich coals stands as a technique whereby coal seams are heated underground to produce tar and gas products. During the in-situ pyrolysis, the injection of heating media and the production of tar and gas are affected by the pore structure and permeability of coal seams. Since pyrolysis of caking tar-rich coals is accompanied by the formation of colloids, the pore structure and permeability of caking tar-rich coals differ from those of non-caking tar-rich coals. Methods Caking tar-rich coals were pyrolyzed at 300, 400, 500, and 600 ℃. During the pyrolysis, the pore parameters of the …

Identification Of Tar-Rich Coal Based On The True Density And Natural Gamma Ray Response Of Coals, Shi Qingmin, Geng Xuhu, Wang Shuangming, Cai Yue, Han Bo, Wang Shengquan, Zhang Zhehao, He Yufei

Coal Geology & Exploration

Objective Tar yield, derived from the Gray-King assay, serves as the sole metric for evaluating tar-rich coal. However, insufficient exploration data hinder its effective application in the fine-scale evaluation of extensive tar-rich coal. Methods Based on binary classification, this study proposed the optimal thresholds for tar-rich coal identification using true density (ρ) and natural gamma-ray (GR) log. Moreover, this study elucidated the intrinsic mechanisms behind the significant petrophysical parameter responses of tar-rich coal. Results and Conclusions Key findings are as follows: (1) Coals with various metamorphic grades differ in identification threshold. For instance, long-flame tar-rich coal, the optimal …

A Log-Based Method For Evaluating The Tar Yield Of Tar-Rich Coal, Tian Han, Li Ning, Wang Shuangming, Wu Hongliang, Feng Zhou, Wang Kewen, Wang Guiwen

Coal Geology & Exploration

Objective As a kind of coal-based oil and gas resource, tar-rich coal is significant for the supply of oil and gas resources, as well as the clean and efficient utilization of coals. Presently, the identification of tar-rich coals primarily depends on the Gray-King assay. In contrast, there is a lack of studies on the accurate identification and evaluation of tar-rich coal using geophysical methods. Methods This study investigated coals in the Jurassic Xishanyao and Badaowan Formations in Santanghu Basin, Xinjiang. Based on petrophysical experiments, as well as the typical log response characteristics of tar-rich coal, this study developed a new …

A Method For Predicting The Tar Yield Of Tar-Rich Coals Based On The Bp Neural Network Using Multiple Indicators Of Coal Petrography And Coal Quality, Qiao Junwei, Wang Changjian, Zhao Hongchao, Shi Qingmin, Zhang Yu, Fan Qi, Wang Duo, Yuan Dandan

Coal Geology & Exploration

Objective Tar yield, the most important coal quality parameter for coal utilization through low-temperature pyrolysis, determines the clean utilization of tar-rich coals. However, various constraints result in limited test data on tar yield in the geological exploration stage of coals, substantially restricting the fine-scale assessment and efficient utilization of tar-rich coals. Methods To achieve more scientific and accurate fine-scale tar-rich coal assessments, this study examined 1073 sets of lithotype and coal quality data obtained previously from a Jurassic coalfield in northern Shaanxi. From these data, 141 sets with 20 lithotype and coal quality parameters regarding macerals, proximate analysis, ultimate analysis, …

Performance Of Carbon Foams Based On Heavy Tar Produced By Tar-Rich Coal Pyrolysis, Zhang Lei, Liu Chunjiang, Song Ruikang, Wang Qi, Chen Ya, Huang Pengcheng

Coal Geology & Exploration

Objective Preparing graphitized foam materials using heavy tar produced by the pyrolysis of tar-rich coals plays a significant role in the high-value utilization of tar-rich coal resources. Methods This study aims to prepare high-performance carbon foam materials by investigating the relationships between various reaction conditions and carbon foam performance. First, using mesophase asphalt prepared with heavy tar as the precursor, carbon foams were developed via the high-temperature self-foaming method. Then, the effects of different reaction temperatures, heating rates, and reaction pressures on the performance of coal tar-based carbon foams were examined. Finally, quadratic multinomial regression equations were established using Box-Behnken …

Molecular Modeling Of Tar-Rich Coals From Northern Shaanxi And Their Molecular Dynamic Characteristics In The Process Of Pyrolysis For Tar Extraction, Guo Wei, Yang Panxi, Yu Zunyi, Yang Fu, Wang Jing, Ma Li, Li Hongqiang, Yang Bolun, Wu Zhiqiang

Coal Geology & Exploration

Objective The pyrolysis process and mechanism of tar-rich coals remain unclear due to their complex structures. Therefore, it is necessary to investigate the structure-activity relationship between their structure and the distributions of their pyrolytic products and determine the mechanism behind their pyrolysis for tar extraction. Methods Focusing on typical tar-rich coals from northern Shaanxi Province, this study calculated and constructed the molecular model of the coals using characterization methods such as carbon-13 nuclear magnetic resonance (¹³C NMR), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS), determining the molecular formula at C₄₄₄H₃₈₀O_{74 …}

Advances In Research On Hydrogenation Saturation Of Polycyclic Aromatic Hydrocarbons In Coal Tar, He Xinfu, Gao Fan, Wu Hongju, Zhang Xiaoqin, Ma Tao, Shi Zhiwei, Zhou Anning, Zhang Yating

Coal Geology & Exploration

Significance Polycyclic aromatic hydrocarbons (PAHs), a predominant component in coal tar, can be used to produce jet fuels with high energy density and thermal stability through hydrogenation saturation. Based on the characteristics of the PAH hydrogenation process, this study proposed that primary challenges in PAH hydrogenation saturation include the resonance energy of PAHs themselves, the spatial site resistance of hydrogenation intermediates, and the competitive adsorption of feedstocks and intermediates on active sites in the catalysts. Progress Based on the review of research progress in catalysts for PAH hydrogenation saturation in recent years, this study analyzed the substantial factor influencing the …

The Newgeneratortm Decentralized Wastewater Treatment System For Non-Sewered Sanitation: Technology Advancement Through Field Evaluation And Modeling, Hsiang-Yang Shyu

USF Tampa Graduate Theses and Dissertations

Non-sewered sanitation systems (NSSS) offer innovative solutions to sanitation challenges in areas lacking basic facilities, utilizing advanced treatment technologies for on-site water reuse. The NEWgenerator (NG), an advanced NSSS developed at the University of South Florida under the Bill & Melinda Gates Foundation’s Reinventing the Toilet Challenge, integrates an anaerobic membrane bioreactor (AnMBR), an ion exchange-based nutrient capture system (NCS), and an electrochlorinator for final disinfection. This study builds on previous field trials of the NG system, focusing on developing, evaluating, and optimizing its water reuse capabilities through field trials, system dynamics modeling, and advanced monitoring techniques.

In the first …

The Growth Of Ethanol In Brazil: Sugarcane, Corn, And A Few Other Things, Fabio Mattos

Cornhusker Economics

Although we can expect more ethanol produced from corn in the coming years, it is unclear whether it will keep expanding at the same pace as in recent years or how much it will contribute to total ethanol production.

One point to keep an eye on is the typical dynamics of markets. If supply and demand conditions and price movements make corn-ethanol more profitable, ethanol plants in Brazil will keep increasing their production. If it makes more economic sense to produce corn-ethanol (as it happened recently), they will use more corn to produce ethanol.

Supply and demand conditions for ethanol, …

Influence Of The Moisture On Fumes Derived From The Anfo Detonation, Andrzej Biessikirski, Mateusz Pytlik, Michał Dworzak, Michał Twardosz, Mariusz Wądrzyk, Rafał Janus

Journal of Sustainable Mining

ANFO is one of the most commonly used explosives in open-pit mining, usually produced by mixing systems on the blast site. One of the problems usually not considered is the moisture”s influence on the stored ammonium nitrate(V). The influence of moisture on fumes and the detonation process has been investigated by placing ammonium nitrate(V) prills in the climatic chamber. In the investigation, the influence was evaluated for ANFO samples which were produced based on the two types of fuel oils. It was concluded that the 3.0% moisture level resulted in the lowest NOx content in both case studies. Further increased …

Energy And Environmental Analyses Of A Solar–Gas Turbine Combined Cycle With Inlet Air Cooling, Ahmad M. Abubaker, Adnan Darwish Ahmad, Binit B. Singh, Yaman M. Manaserh, Loiy Al-Ghussain

Institute of Research for Technology Development Faculty Publications

Sensitivity to ambient air temperatures, consuming a large amount of fuel, and wasting a significant amount of heat dumped into the ambient atmosphere are three major challenges facing gas turbine power plants. This study was conducted to simultaneously solve all three aforementioned GT problems using solar energy and introducing a new configuration that consists of solar preheating and inlet-air-cooling systems. In this study, air was preheated at a combustion chamber inlet using parabolic trough collectors. Then, inlet air to the compressor was cooled by these collectors by operating an absorption cooling cycle. At the design point conditions, this novel proposed …

Examining The Progress In Additive Manufacturing In Supporting Lean, Green And Sustainable Manufacturing: A Systematic Review, Catherine Maware, Rumbidzai Muvunzi, Tinotenda Machingura, Ilesanmi Daniyan

Institute for Sustainable Manufacturing Faculty Publications

The quest for waste reduction and the development of manufacturing processes that meet the economic, social and environmental requirements necessitate this study. Additive manufacturing is an emerging digital technology that can be used to seamlessly develop a product through material deposition in layers. The study aims to investigate the progress made in the development of additive manufacturing to support lean, green and sustainable manufacturing. The study employs a systematic literature review approach, specifically the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). A total of 158 articles identified from different academic databases that detailed empirical, conceptual and theoretical findings …

Balloon Borne Gps-Enabled Radiosondes That Enable Simultaneous Multi-Point Atmospheric Sensing With A Single Ground Station, Peter A. Ribbens

Doctoral Dissertations and Master's Theses

Radiosondes are balloon borne atmospheric instruments that are a critical tool for understanding dynamics in the lower layers of the atmosphere. The low-cost radiosondes developed in the Space and Atmospheric Instrumentation Lab have been further developed to improve the system's use as a science-quality atmospheric instrument that is unique in its ability to simultaneously track multiple sondes with a single ground station. Sensors to measure temperature and pressure were added to improve measurements of the atmospheric state. A printed circuit board shield and 3D-printed shell were designed to make mass manufacturing possible. A thermistor-based temperature sensor was developed and tested …

Optimization Of A Plate Beam System For Energy Harvesting Using A Piezoelectric Material, Jose Manuel Almendros Espantaleon

Doctoral Dissertations and Master's Theses

With a continuously growing demand for power, driven by the need to reduce our environmental footprint, this research provides an examination of the potential of energy harvesting with smart materials technology and its practical applications. The energy harvesting system considered here works on generating energy through vibrations of a piezoelectric material beam which will undergo sustained vibrations due to flow of air over its surface. It is assumed that sustained limit cycle oscillations of this system will occur at the flutter velocity. This research creates an optimization framework to obtain the best values of parameters that will result in the …

Enhancing Water Sustainability In North Africa: Literature Review And Synthesis Of Current Knowledge Gaps In Sudan, Osman M. A. Adam, Aaron R. Mittelstet, Derek M. Heeren, Troy E. Gilmore

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

This study delves into the critical role of groundwater in addressing global water challenges, with a focus on the Nubian Sandstone Aquifer System (NSAS) in North Africa. Groundwater constitutes a source of potable water, irrigation, and industrial use, especially in arid regions where surface water is limited. We analyzed the status of water quantity, withdrawals, recharge, and geological characteristics in the NSAS, specifically in Sudan, Egypt, Libya, and Chad. Though the NSAS is largely an untapped resource, we evaluated various scenarios to determine the quantity of cropland that can be sustainably irrigated. The NSAS is located in an arid region, …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Factors Influencing The Productivity And Technology Optimization Of Horizontal Wells For Moderately Deep Coalbed Methane In The Northern Zhengzhuang Block, Zhang Cong, Li Kexin, Jia Huimin, Zhang Wuchang, Yang Ruiqiang, Li Jun, Wang Qi, Hou Weiming

Coal Geology & Exploration

[Objective] Hydraulic fracturing of vertical wells was adopted during the early production of moderately deep coalbed methane (CBM) of the northern Zhengzhuang block in the Qinshui Basin, generally yielding low productivity and inefficiency. In contrast, single-casing fracturing of horizontal wells has increased the single-well production to 10‒50 times that of vertical wells, establishing horizontal wells as the dominant development well type. However, the horizontal wells differ greatly in CBM production. This study aims to determine the factors influencing the productivity of horizontal wells using staged fracturing for moderately deep CBM in the northern Zhengzhuang block and improve the production performance. …

Characteristics Of The Pore And Seepage System Of Deep Coalbed Methane In The Baijiahai Uplift, Junggar Basin, Xinjiang, Chen Heqing, Yang Zhaobiao, Li Daoqing, Xu Miaomiao, Liang Yuhui, Liu Changqing, Wang Yuqiang

Coal Geology & Exploration

[Objective] Xinjiang boasts abundant deep coalbed methane (CBM) resources, with Jurassic coal seams in the Baijiahai uplift of the Junggar Basin identified as a favorable target area for deep CBM exploration and exploitation. The pore and seepage system of deep CBM directly determines its recoverability. [Methods] Based on appraisal well Caimei 2-004H drilled the most recently in the Xinjiang oilfield in 2023, this study investigated in detail the pore and seepage system of coals in the Jurassic Xishanyao Formation in the Baijiahai uplift using scanning electron microscopy (SEM) observations, mercury injection capillary pressure (MICP), low-temperature liquid nitrogen adsorption, and carbon …

Impacts Of Observation Line Layout Morphology And Survey Point Missing On The Inversion Of Predicted Parameters Of Mining Subsidence, Guo Qingbiao, Yu Qing, Zheng Meinan, Luo Jin

Coal Geology & Exploration

[Objective] Accurate prediction parameters for mining subsidence are important basis for full cycle green coal mining, while inversion based on the subsidence data of observation lines serves as the main method to obtain these parameters. [Methods] To quantitatively analyze the impacts of the observation line layout morphology and survey point missing on the inversion of prediction parameters for mining subsidence, this study developed a probability integral model-based inversion method for these parameters using the chimpanzee optimization algorithm (ChOA). Using this method combined with digital simulation experiments, this study predicted subsidence parameters under six observation line morphologies and survey point missing …

Fracturing Evolutionary Law And Energy Utilization Efficiency Of Green Sandstones Under Different Loading Rates, Zhao Huanshuai, Pan Yongtai, Qiao Xin, Wang Xingyu, Yu Chao, Huang Jiacheng

Coal Geology & Exploration

[Objective] This study aims to explore the fracturing evolutionary laws and energy utilization efficiency of rocks under different loading rates is a pressing issue in the field of rock fragmentation and processing. [Methods] To this end, the microscopic parameters of green sandstones were calibrated based on laboratory tests, followed by the identification of relationships between the macro- and microscopic mechanical responses of the sandstones. Using Particle Flow Code (PFC), this study investigated the stress-strain curves and stress chain distribution of green sandstones under different loading rates. Then, based on the fracturing and crack characteristics, this study analyzed the fracturing evolutionary …

Hydrochemical Characteristics And Genetic Mechanism Of Geothermal Water In The Wandong Geothermal Area Along The Moxi Fault In Western Sichuan, Huang Xun, Zhang Yunhui, Li Xiao, Lyu Guosen, Guo Hongyang

Coal Geology & Exploration

[Objective] Geothermal energy exploitation is identified as a vital way to achieve the goals of peak carbon dioxide emissions and carbon neutrality. The Moxi fault, located in the southern segment of the Xianshuihe fault zone in western Sichuan, boasts abundant geothermal resources, serving as a significant area for subsequent geothermal energy exploitation. [Methods] This study investigated the hydrogeochemistry of the Wandong geothermal area along the Moxi fault, analyzed the water-rock interaction process in the area based on the hydrochemical correlation, and calculated the reservoir temperatures and the mixing ratios of cold and hot water using geothermometers and the silica-enthalpy mixing …

Experimental Study On The Mechanics And Deformation Failure Characteristics Of Multi-Source Coal-Based Solid Waste Cemented Backfill, Yang Ke, Zhang Jiqiang, He Xiang, Wei Zhen, Zhao Xinyuan

Coal Geology & Exploration

[Objective] In order to study the mechanical properties and deformation failure laws of multi-source coal-based solid waste cemented backfill (CBSWCB), the uniaxial compression, acoustic emission response and microstructure test experiments were carried out with 5 types of typical coal-based waste. [Methods] The factors influencing the uniaxial compressive strength of CBSWCB, as well as their interaction, were analyzed, and a four-dimensional spatial visualization model of the factors influencing the compressive strength based on their interactions was established. Besides, the mechanical evolution characteristics and macroscopic deformation failure laws under uniaxial compression conditions were elaborated by referring to the acoustic emission and microstructure …

Application Of Microseismic Monitoring System For Coal Mines To The Prevention And Control Of Water Disasters On Working Face Roofs, Fan Xin, Cheng Jianyuan, Li Sheng, Duan Jianhua, Fan Tao, Li Bofan, Wang Yanbo

Coal Geology & Exploration

[Objective] Increasing coal mining depth in coal mines has caused increasingly prominent risks of water disasters on working face roofs, which restrict the green, safe, and efficient coal mining in China’s coal mines. Therefore, there is an urgent need for new technologies for the monitoring and early warning of these water disasters. [Methods] This study explored the application of the joint well-ground microseismic monitoring system to the prevention and control of water disasters on working face roofs, achieving transparent, intelligent monitoring and early warning of water disaster risks. In this system, microseismic sensor arrays are arranged on the surface above …

Geological Structures Fine Monitoring Using Seismic-While-Tunneling Technique In Wangpo Mine, Zhao Huibo, Qin Si, Chen Chao, Guan Qi, Zhao Xingwei, Che Jianhang

Coal Geology & Exploration

Traditional tunnel seismic advance detection technology is limited by the use of explosives, the need for mining stoppages, prediction speed, detection range, and capabilities, making it challenging to meet the high-precision geological structure detection requirements of intelligent tunneling faces. In response, the seismic-while-tunneling technique utilizes the vibration of the roadheader cutting the coal wall as the seismic source. This method employs real-time data upload, automatic processing, and dynamic imaging. By leveraging information technology and software support, and utilizing real-time continuous super-saturation stacking supported by massive data, the imaging precision of geological anomalies ahead of the mining face is significantly enhanced. …

Pneumatic Directional Drilling Technology And Equipment For Broken-Soft Coal Seams In Underground Coal Mines, Tian Hongliang, Zhang Jinbao, Wang Li, Fang Jun, Wang Jianqiang

Coal Geology & Exploration

[Objective] The geological conditions of coal seams in China are complex, with a wide distribution of broken-soft coal seams, and a large number of wells have the problems of high gas and coal-gas outburst. Currently, borehole gas drainage is an effective measure for preventing and controlling the gas disasters. [Methods] In response to the problems of uncontrollable drilling trajectory, shallow drilling depth, large blind spots of drainage in conventional rotary drilling process of broken-soft coal seams, as well as multiple stuck drilling accidents, great difficulty in drilling and low drilling efficiency in conventional directional drilling processes, the development history and …

Build-Up Rate Prediction Of Rotary Steerable Tools Based On Delay Differentiation, Li Fei, Zhang Nan

Coal Geology & Exploration

[Objective] Accurate build-up rate prediction of rotary steerable tools is a prerequisite to achieve the precise control of tools. In order to grasp the variation law of the build-up rate of the rotary steerable bottom-hole assembly (RSBHA). [Methods] Based on the structural charaeteristics of the tool, the Euler-Bernoulli beam equation method is used to analyz the forces outing on the composite RSBHA. At the same time, the calculation method of the tool deflection angle in different sections and the bit pre-drilling deflection angle was obtained with consideration to the geometric relationship of the bottom-hole assembly, and the distance between the …

Analysis Of Three-Dimensional Nonlinear Fluid-Solid Coupling Vibration Characteristics Of Coalbed Methane Abandoned Well Plugging String, Xu Zhixin, Wan Jifang, Hong Yi, Liu Hangming, Yi Xianzhong, Diao Binbin, Wang Yanbin

Coal Geology & Exploration

[Objective] The plugging quality of cement plug in abandoned coalbed methane wells is critical to preventing pollutant leakage. Current standards for handling these wells involve simple mud pump injection, which often results in cement plugs with issues like particle agglomeration, bubbles, and micropores. These defects reduce the strength of the cement plug and compromise its sealing performance. [Methods] To address this, vibration technology is applied to the plugging operation, using a specialized tool to induce vibrations in the pipe string. This process enhances the fluidity of the cement slurry via the transmission of vibration energy, thereby improving the plugging quality …

Spatial Distribution And Influencing Factors Of Microseismic Events In Unequal-Length Mining Faces In Coal Mines, Zhou Jinyan, Yang Hongzeng, Gao Jietao

Coal Geology & Exploration

[Objective] The varying length of a mining face along its dip direction or adjusting mining significantly increases water inrush risks of the mining face. This study investigate the hazards and influencing factors brought by unequal length arrangements to the mining face is one of the key issues in deepening the research on coal mine water hazard prevention and ensuring the safe mining face. [Methods] With the No. 15240 mining face, consisting of a narrow part, a wide part, and a slope, in the Jiulong Coal Mine of the Jizhong Energy Fengfeng Group as the engineering background, a large amount of …