Engineering Commons^™

An Improved Method For Characterizing Coal Metamorphism By Xrd, Wang Chao, Zhao Younan, Wang Zhenwei, Lu Zhaolin

Coal Geology & Exploration

At present, the X-ray measurement method of coal metamorphism has the problem that the γ band is not well divided, the δ peak information is not used, and the background of the bottom is unreasonable. The X-ray diffraction pattern of coal with different metamorphosed degrees is compared and studied. It is proposed to correct the metamorphic coefficient formula by using the information of the slope of the 002 peak, the extended half-height width and the δ peak without deducting the so-called background information. The calculation of the XRD patterns of coal samples with different degrees of metamorphism is verified. The …

A Review Of 30 Years Of Research Using The Cpd Model, Thomas H. Fletcher

Faculty Publications

The chemical percolation devolatilization (CPD) model for coal pyrolysis was first published in 1989, and a completed version that included the vapor–liquid equilibrium model and cross-linking model was published in 1992. The CPD model was one of three pyrolysis models developed using a lattice model to account for the chemical structure of the coal and was directly based on solid-state ¹³C nuclear magnetic resonance (NMR) measurements of the coal structure. A correlation of coal structure parameters measured by NMR spectroscopy was performed to permit use of the CPD model to determine pyrolysis rates and yields of tars and light …

Micro Ct-Based Meticulous Characterization Of Porosity Evolution Of Coal In The Process Of Biodegradation, Dong Zhiwei, Guo Hongyu, Xia Daping, Liu Xile, Bai Yang, Zhao Guojun

Coal Geology & Exploration

To explore the bio-permeability enhancing effect via methanogen treatment on different rank coals after anaerobic fermentation, micro-CT was used to analyze the change characteristics of pore structure of coal before and after biodegradation. At the same time, the adsorption characteristics of methanogens on the coal surface after anaerobic biodegradation were observed by scanning electron microscopy to analyze the reasons for the effect difference of biological transformation of different rank coals. The results show that the porosity and total throat length of the coal samples biodegraded increase and the connectivity of the pores is enhanced, it is indicated that coal samples …

Occurrence Of Antimony In Magmatic Intrusive Coal Seam: A Case Study From The Wolonghu Coal Mine, Huaibei Coalfield, China, Ou Jinping, Zheng Liugen, Wei Xiangping, Liu Sikui, Li Liyuan, Liu Meng, Huang Xiaoyu

Coal Geology & Exploration

In order to investigate the influence of magmatic alteration on the occurrence characteristics of antimony in coal seam, 12 samples of magmatic magma and coal were collected from Wolonghu coal mine in Huaibei coalfield, Anhui Province, and the content of Sb was determined by atomic fluorescence spectrometry(AFS). The coal quality parameters are analyzed. The results are as follows:the coal in Wolonghu magmatic intrusion area has the characteristics of ultra-low volatile matter, medium ash content and ultra-low sulfur content. And the main forms of sulfur in coal are organic sulfur and pyrite sulfur. Under the influence of magmatic hydrothermal solution, ash …

Evaluating Volumetric Strain As A Predictor Of Yield And Peak Strength For The Multistage Triaxial Test: A Case Study With Utah Coal Specimens, Emmanuel Orilogi

Graduate Theses & Non-Theses

Failure envelopes used to characterize the shear strength of geological materials are generally obtained through conventional triaxial testing of multiple specimens and most of the specimens are heterogonous and expensive to obtain. Therefore, the multistage triaxial test was introduced to make use of a single specimen for material strength characterization, compared to the conventional triaxial test that requires at least three specimens. In the multistage triaxial test, the challenge to obtaining meaningful data is identifying when to terminate each loading stage. The goal is to be as close to the peak strength of the material but below the stress threshold …

Micro-Ct-Based Approaches For Quantifying The Morphology Of Pulverized Char Particles, Scott Jorgensen, Simcha L. Singer

Mechanical Engineering Faculty Research and Publications

Morphological analysis of pulverized coal char particles using two-dimensional (2-D) cross-sectional imaging has been widely employed, but its accuracy has not been adequately assessed. In this study, pulverized coal char particles are imaged in three dimensions (3-D) using high-resolution X-ray microcomputed tomography (micro-CT). Particle volume, macropore volume, and macroporosity are measured in three dimensions and analyzed as a function of distance from the particle center using averaging at each radial location. A technique for extracting each particle’s average wall thickness, another morphological parameter used for classification, is also presented based on micro-CT imaging. When applied to pulverized bituminous coal char …

Low-Cost Carbon Fibre Derived From Sustainable Coal Tar Pitch And Polyacrylonitrile: Fabrication And Characterisation, Omid Zabihi, Sajjad Shafei, Seyed Mousa Fakhrhoseini, Mojtaba Ahmadi, Hossein Ajdari Nazarloo, Rohan Stanger, Quang Anh Tran, John Lucas, Terry Wall, Minoo Naebe

Research outputs 2014 to 2021

Preparation of high-value pitch-based carbon fibres (CFs) from mesophase pitch precursor is of great importance towards low-cost CFs. Herein, we developed a method to reduce the cost of CFs precursor through incorporating high loading of coal tar pitch (CTP) into polyacrylonitrile (PAN) polymer solution. The CTP with a loading of 25% and 50% was blended with PAN and their spinnability was examined by electrospinning process. The effect of CTP on thermal stabilization and carbonisation of PAN fibres was investigated by thermal analyses methods. Moreover, electrospun PAN/CTP fibres were carbonised at two different temperatures i.e., 850 °C and 1200 °C and …

Microwave And Ultrasonic Assisted Synthesis Of Zeolites From Coal Fly Ash In Batch And Circulating Batch Operation, Tahani Hassn Aldahri

Electronic Thesis and Dissertation Repository

This research was focused on the production of zeolites from CFA throughutilizing ultrasound and microwave power. The initial conventional heating process of 6 h prior to microwave irradiation for samples with high solid-to-liquid (S/L) ratio (CFA mass/ NaOH solution volume) led to a higher yield of zeolite and decreased the synthesis time and consumption of energy,while keeping the high quality of the synthesized zeolite intact. The crystal growth of the nuclei generated over 6 h of conventional hydrothermal treatment was enhanced by the post-microwave heating. Ultrasound-assisted zeolitizationCFA was also applied in this research.

When ultrasound energy was applied after hydrothermal …

Development Of Self-Ignition Mechanisms And Conditions Carbon Deposits And Terricons, A.E. Vorobev, R.B. Dzhimieva

Gorniy vestnik Uzbekistana

In this article, the mechanisms of spontaneous combustion of coal and coal-bearing rocks, as well as physical and mathematical modeling of the development of processes and the source of spontaneous combustion in the local zone of the coal-rock massif, are studied. predict the occurrence and prevention of these very dangerous phenomena.

Technology And Method Of Cbm Concurrent Exploration During Coal Resources Exploration, Lin Yabing, Qin Yong, Duan Zhonghui, Ma Dongmin

Coal Geology & Exploration

The coal seam serves as a geological carrier for CBM, and exploration of CBM and coal resources is a man-datory requirement for the management of national mineral resources. Based on the practice of project exploration in recent years, it analyzed the evaluation criteria of CBM resources in the process of coal resources exploration. On this basis, the exploration ideas, exploration methods, tasks, report preparations have proposed a method system for CBM in the ex-ploration of coal resources. According to the particularity of CBM exploration work methods, CBM seismic, well logging, drilling, well log, gas drainage, and engineering quality acceptance methods …

Analysis On The Development Characteristics And Influencing Factors Of Gas Pores In Coal, Zhang Hui, Wu Jing, Yuan Liying, Song Xiaozhong, Lin Bowei

Coal Geology & Exploration

Based on the study of coalfield geology and coal petrology, using field emission scanning electron microscopy(FESEM) as the main observation method, nanoscale pore research on coals was carried out for different regions, different geological ages and different metamorphic degrees. The results show that gas pores in coal are the pores left by coalbed methane(gas) generation, accumulation and escape during coal metamorphism, are secondary porosity. The pore diameter is mainly at nanometer size and round shape, with uneven density and distribution. The gas pore is intensive, often forms gas pore group, gas pore zone and gas pore nest. The gas pore …

Simulation Of Influence Of Coal-Based Industry On Water Resources Bearing System, Yalin Chen, Wangsheng Gui, Qianjin Dong, Ye Chun, Haotian Wu

Journal of System Simulation

Abstract: The contradictory spatial distribution between China's coal resources and water resources has become the stress to sustainable development of regional ecological environment and social economy. The paper presents interactive simulation model of regional water resources bearing system based on System Dynamics; and then Ningxia Hui Autonomous Region is used as an example, the dynamic process of local water bearing system was simulated under different scenarios of planning. The simulation results show that regional sustainable development of water resources would be achieved if the resources are allocated based on the market, while the gap between supply and demand of regional …

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 …

Reliability Issues Caused By The Retirement Of Large Thermal Generation Facilities: An Irish Case Study, Kyle Lawson, Jane Courtney

Conference papers

Like all developed countries Ireland faces increasing pressure to reduce their carbon footprint. Part of the governments plans include the scaling back of fossil fuel generation facilities and increasing renewable resources. Moneypoint is Irelands only coal fired generation station. In 2025 Moneypoint is due to reach the end of its life cycle. At this point the Irish government will have to make a decission on the future of the generation facility. Currently Moneypoint is responsible for the generation of approximately 10 % of Irelands energy needs. In this paper, the removal of Moneypoint from the Irish generation portfolio will be …

Evaluation Of Coal Seam Gas Drainability For Outburst-Prone And High-Co2-Containing Coal Seam, Lei Zhang, Ting X. Ren, Naj Aziz, Cun Zhang

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents the results of an evaluation study of gas drainability in the Bulli seam in the Southern Coalfield of the Sydney Basin, NSW, Australia, where the coal seam gas (CSG) contains a high proportion of carbon dioxide (CO 2 ). Historically the gas drainability in some particular areas of this coal seam was found to be particularly poor, which posed a significant challenge to gas predrainage. As a result, a large volume of greenhouse gases were released to the atmosphere during mining of the coal seam. Furthermore, the high gas content associated with the CO 2 -rich composition …

A Mixture Of Coal Wash And Fly Ash As A Pavement Substructure Material, Dong Wang, Miriam Tawk, Buddhima Indraratna, Ana Heitor, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers: Part B

The reuse of waste materials in engineering projects has become the subject of many research efforts worldwide as it provides economical as well as environmental benefits. Coal wash (CW) and fly ash (FA) are example waste materials that can be used as alternative aggregates in transportation infrastructure projects, specifically as base and subbase materials in roads. Class C FA has been extensively used as a stabilizing material due to its hardening potential. However, Class F fly ash, a non­pozzolanic material when used alone, has not been considered in past research projects. In this study, Class F fly ash is mixed …

Review Of Carbonaceous Annealing Effects On O2 And Co2 Coal Reactivity, Troy Michael Holland, Thomas H. Fletcher, Osvalda Senneca

Faculty Publications

Coal is, and will remain for the foreseeable future, a critical energy production resource. Advanced models of coal conversion behavior in air and oxy-coal environments enhance the boiler operational efficiency and design optimization. Although coal conversion models have continuously improved over decades of research, not all aspects of coal particle heating and conversion have received equal treatment. Coal particle annealing is one aspect of the coal conversion process that is simultaneously highly sensitive to the conversion environment, exceptionally impactful on coal chemistry, and frequently neglected in coal models. However, the current body of literature has explored numerous aspects of coal …