Engineering Commons^™

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 …

Selection Of Fan(S) To Dilute Dpm For Multi-Seam Board And Pillar Coal Mines Using Hardy Cross And Cpm Methods, Ramakrishna Morla, Shivakumar Karekal

Faculty of Engineering and Information Sciences - Papers: Part B

Multi-seam coal mining comprises of a large number of working sections. A well-organized ventilation system is necessary to supply adequate air quantities to all working sections and to dilute diesel particulate matter (DPM) within the statutory limits. In this paper, an attempt has been made to optimize fan(s) operating points in a multi-seam mine using a combination of Hardy-Cross and critical path methods. Selection of parallel fan sizes was further explored using computational fluid dynamics (CFD). Simulation results show that operating two surface parallel fans results in low total air power and low fans pressure

A Review On Numerical Solutions To Self-Heating Of Coal Stockpile: Mechanism, Theoretical Basis, And Variable Study, Jian Zhang, Ting X. Ren, Yuntao Liang, Zhongwei Wang

Faculty of Engineering and Information Sciences - Papers: Part A

Self-heating or even spontaneous combustion of stockpiled coal, which is likely to outbreak under favourable circumstances during its transport, process, and storage, is a long-standing thermal dynamic hazard. This hazard is harmful in diverse aspects: causing loss of coal resource and caking property, raising safety concerns upon occurrence of open fire, and giving off noxious/greenhouse effect gases. Due to the complexity of involved physical process (e.g. heat and mass transport) and chemical process (e.g. coal oxidation), formulating an analytical solution to the problem with or even without a transient approach would be a daunting task and the problem is thus …

Drained And Undrained Shear Behavior Of Compacted Coal Wash, Ana Heitor, Buddhima Indraratna, Chazath Kaliboullah, Cholachat Rujikiatkamjorn, Geoffrey Mcintosh

Faculty of Engineering and Information Sciences - Papers: Part A

Coal wash is a granular waste material that is readily available in the vicinity of coal mining operations. While its potential use in structural fills has been recognized in the past, the effects of particle breakage on the geomechanical performance of the material have not been thoroughly investigated. In this paper, an experimental study on a selected coal wash is undertaken to characterize the influence of compaction and particle breakage on its corresponding stress-strain behavior. Particular emphasis is given to the role of compaction energy level and associated breakage incurred during compaction on the drained and undrained shearing behavior. The …

Membrane Distillation And Membrane Electrolysis Of Coal Seam Gas Reverse Osmosis Brine For Clean Water Extraction And Naoh Production, Hung Duong, Mikel C. Duke, Stephen Gray, Bart Nelemans, Long D. Nghiem

Faculty of Engineering and Information Sciences - Papers: Part A

Membrane distillation (MD) and membrane electrolysis (ME) were evaluated for simultaneous fresh water extraction and NaOH production from a mixture of NaCl and NaHCO3 to simulate the composition of coal seam gas (CSG) reverse osmosis (RO) brine. Experimental results demonstrate the potential of MD for producing fresh water and simultaneously concentrating CSG RO brine prior to the ME process. MD water flux was slightly reduced by the increased feed salinity and the decomposition of bicarbonate to CO2 during the concentration of CSG RO brine. MD operation of CSG RO brine at a concentration factor of 10 (90% water recovery) was …

Transient Cfd Modelling Of Low-Temperature Spontaneous Heating Behaviour In Multiple Coal Stockpiles With Wind Forced Convection, Jian Zhang, Yuntao Liang, Ting X. Ren, Zhongwei Wang, Gongda Wang

Faculty of Engineering and Information Sciences - Papers: Part A

Spontaneous heating of coal stockpile has long been a thermal dynamic hazard during coal storage, processing, and transport. A transient non-equilibrium thermal CFD model has been developed to study the low-temperature self-heating behaviour of coal in multiple stockpiles under different prevailing wind conditions. Modelling results from the initial steady wind flow simulation indicate that a wake region can be induced on the leeward side of each coal stockpile. Pressure coefficient drops when the wind stream encounters or leaves a stockpile and the pressure coefficient profiles of multiple stockpiles tend to have more resemblance with a wider spacing. The first stockpile …

Investigations Into The Identification And Control Of Outburst In Australian Underground Coal Mines, Dennis J. Black

Faculty of Engineering and Information Sciences - Papers: Part B

Australian coal mines currently use gas content to assess outburst risk. The gas content threshold values for each mine are indirectly determined from measurement of gas volume liberated from 150 g coal samples during Q3 residual gas content testing. It has been more than twenty (20) years since this method, known as DRI900, was presented to the Australian coal industry, and in that time there have been significant changes in mining conditions and the outburst threshold limits used at the benchmark Bulli seam mines.Current coal mining legislation in both Queensland [7] and New South Wales [6] provide little guidance in …

Graphene/Pvdf Flat-Sheet Membrane For The Treatment Of Ro Brine From Coal Seam Gas Produced Water By Air Gap Membrane Distillation, Yun Chul Woo, Youngjin Kim, Wang-Geun Shim, Leonard D. Tijing, Minwei Yao, Long D. Nghiem, June-Seok Choi, Seung-Hyun Kim, Ho Kyong Shon

Faculty of Engineering and Information Sciences - Papers: Part A

No abstract provided.

A Study Of The Behaviour Of Fresh And Coal Fouled Ballast Reinforced By Geogrid Using The Discrete Element Method, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers: Part A

Geogrids are widely used in ballasted rail tracks for reinforcement and stabilisation. During train operation, ballast becomes contaminated or fouled due to infiltration of fines from the surface, mud pumping from the subgrade, and degradation, which decreases the performance of the geogrids. This paper presents the results of a laboratory and numerical simulation to study the effect that coal fines have on the interface between ballast and geogrid. The stress-strain behaviour of fresh and fouled ballast reinforced by geogrid was investigated via a series of large scale direct shear tests in the laboratory and numerical simulations using the Discrete Element …

Strength And Bonding In Reduced Ironsand-Coal Compacts, R J. Longbottom, B J. Monaghan, S A. Nightingale, J G. Mathieson

Brian Monaghan

In this investigation, the strength and bonding within reduced ironsand-coal compacts were studied, with the aim of better understanding the binding mechanisms in the reduced compacts and, based on this understanding, to improve their strength. Ironsand ore and sub-bituminous coal were mixed and pressed into compacts, which were reduced by heating in a thermogravimetric furnace to temperatures between 1273 and 1573 K under argon. The progress of the reaction was monitored by measuring the weight loss with time. The reduced compacts were found to have low strength in compression testing. The main form of bonding between the reduced ironsand particles …

Dem Simulation Of The Behaviour Of Geogrid Stabilised Ballast Fouled With Coal, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn

Cholachat Rujikiatkamjorn

Geogrids are commonly used in railway construction for reinforcement and stabilisation. When railway ballast becomes fouled due to ballast breakage, infiltration of coal fines, dust and subgrade soil pumping, the reinforcement effect of geogrids decreases significantly. This paper presents results obtained from Discrete Element Method (DEM) to study the interface behaviour of coal-fouled ballast reinforced by geogrid subjected to direct shear testing. In this study, irregularly-shaped aggregates (ballast) were modelled by clumping together 10-20 spheres in appropriate sizes and positions. The geogrid was modelled by bonding a large number of small spheres together to form the desired grid geometry and …

Compaction Of Coal Wash As Reclamation Fill, Buddhima Indraratna, Cholachat Rujikiatkamjorn, Gabriele Chiaro

Cholachat Rujikiatkamjorn

In this paper, detailed laboratory investigations were conducted on coal wash produced at coal mine, Wollongong, New South Wales, Australia. Geotechnical tests were conducted to determine the particle size distribution, compaction characteristics, shear resistance and collapse potential. The compaction tests were conducted under dry and submerged condition to examine the compactability and the strength of the coal wash. The laboratory tests show that compacted coal wash has good potential as effective fill for embankments, and land reclamation. Although coal wash is compacted under submerged condition, increased level of compaction has minimal effect.

Dem Simulation Of The Behaviour Of Geogrid Stabilised Ballast Fouled With Coal, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn

Buddhima Indraratna

Geogrids are commonly used in railway construction for reinforcement and stabilisation. When railway ballast becomes fouled due to ballast breakage, infiltration of coal fines, dust and subgrade soil pumping, the reinforcement effect of geogrids decreases significantly. This paper presents results obtained from Discrete Element Method (DEM) to study the interface behaviour of coal-fouled ballast reinforced by geogrid subjected to direct shear testing. In this study, irregularly-shaped aggregates (ballast) were modelled by clumping together 10-20 spheres in appropriate sizes and positions. The geogrid was modelled by bonding a large number of small spheres together to form the desired grid geometry and …

Compaction Of Coal Wash As Reclamation Fill, Buddhima Indraratna, Cholachat Rujikiatkamjorn, Gabriele Chiaro

Buddhima Indraratna

In this paper, detailed laboratory investigations were conducted on coal wash produced at coal mine, Wollongong, New South Wales, Australia. Geotechnical tests were conducted to determine the particle size distribution, compaction characteristics, shear resistance and collapse potential. The compaction tests were conducted under dry and submerged condition to examine the compactability and the strength of the coal wash. The laboratory tests show that compacted coal wash has good potential as effective fill for embankments, and land reclamation. Although coal wash is compacted under submerged condition, increased level of compaction has minimal effect.

Deformation Of Coal Fouled Ballast Stabilized With Geogrid Under Cyclic Load, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn

Buddhima Indraratna

This paper presents the results of laboratory investigations into the deformation of coal fouled ballast stabilized with geogrid at various degrees of fouling. A novel track process simulation apparatus was used to simulate realistic rail track conditions subjected to cyclic loading, and the void contamination index (VCI) was used to evaluate the level of ballast fouling. The experimental results show that coal fines act as a lubricant, causing grains of ballast to displace and rotate, and as a result, accelerate its deformation. However, coal fines also reduce ballast breakage because of a cushioning effect, that is, by reducing interparticle attrition. …

Dem Simulation Of The Behaviour Of Geogrid Stabilised Ballast Fouled With Coal, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers: Part A

Geogrids are commonly used in railway construction for reinforcement and stabilisation. When railway ballast becomes fouled due to ballast breakage, infiltration of coal fines, dust and subgrade soil pumping, the reinforcement effect of geogrids decreases significantly. This paper presents results obtained from Discrete Element Method (DEM) to study the interface behaviour of coal-fouled ballast reinforced by geogrid subjected to direct shear testing. In this study, irregularly-shaped aggregates (ballast) were modelled by clumping together 10-20 spheres in appropriate sizes and positions. The geogrid was modelled by bonding a large number of small spheres together to form the desired grid geometry and …

Closure To "Deformation Of Coal Fouled Ballast Stabilized With Geogrid Under Cyclic Load" By Buddhima Indraratna, Ngoc Trung Ngo, And Cholachat Rujikiatkamjorn, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers: Part A

The writers highly appreciate the keen feedback provided by the discusser and also for raising some other important aspects of the experimental program. While the writers are in general agreement with the discusser’s comments, some points warrant further clarification.

Goaf Frictional Ignition And Its Control Measures In Underground Coal Mines, Gaofeng Wang, Ting Ren, Christopher David Cook

Faculty of Engineering and Information Sciences - Papers: Part A

Goaf Frictional Ignition (GFI) poses a serious threat to the safety of underground coal mines, and has caused many underground fires and catastrophic explosions. This paper examined occurrences of GFI incidents and the underlying mechanisms of ignition source and environment. Most of these incidents were attributed to rock on rock frictional ignition. The eventuation of frictional ignition relies on the presence of hot spots with enough incendive ignition energy, which requires a minimum threshold sliding distance and sliding velocity. The incendivity of the environment can be enhanced by the presence of liquid carbon hydrogen, the increase of virgin rock temperature, …

Hard Automation Trends In Australian Underground Coal Mines, Stephen Van Duin, Luke Meers, Gary Gibson

Faculty of Engineering and Information Sciences - Papers: Part A

As productivity in coal extraction demands increase in underground coal mines, the industry is faced with finding new ways to support production without jeopardising safety. In modern mines the capacity and scale of longwall coal extraction has steadily increased to a point that support processes are failing to keep pace. In particular, roadway development is continually placed on the critical path of activities which maintain mine production, so any inefficiency in this area is quickly exposed. Original equipment manufacturers are under immense pressure to modify their machines to be more interconnected with each other, with machine communication and logistical sharing …

Deformation Of Coal Fouled Ballast Stabilized With Geogrid Under Cyclic Load, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents the results of laboratory investigations into the deformation of coal fouled ballast stabilized with geogrid at various degrees of fouling. A novel track process simulation apparatus was used to simulate realistic rail track conditions subjected to cyclic loading, and the void contamination index (VCI) was used to evaluate the level of ballast fouling. The experimental results show that coal fines act as a lubricant, causing grains of ballast to displace and rotate, and as a result, accelerate its deformation. However, coal fines also reduce ballast breakage because of a cushioning effect, that is, by reducing interparticle attrition. …

Compaction Of Coal Wash As Reclamation Fill, Buddhima Indraratna, Cholachat Rujikiatkamjorn, Gabriele Chiaro

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, detailed laboratory investigations were conducted on coal wash produced at coal mine, Wollongong, New South Wales, Australia. Geotechnical tests were conducted to determine the particle size distribution, compaction characteristics, shear resistance and collapse potential. The compaction tests were conducted under dry and submerged condition to examine the compactability and the strength of the coal wash. The laboratory tests show that compacted coal wash has good potential as effective fill for embankments, and land reclamation. Although coal wash is compacted under submerged condition, increased level of compaction has minimal effect.

Strength And Bonding In Reduced Ironsand-Coal Compacts, R J. Longbottom, B J. Monaghan, S A. Nightingale, J G. Mathieson

Faculty of Engineering and Information Sciences - Papers: Part A

In this investigation, the strength and bonding within reduced ironsand-coal compacts were studied, with the aim of better understanding the binding mechanisms in the reduced compacts and, based on this understanding, to improve their strength. Ironsand ore and sub-bituminous coal were mixed and pressed into compacts, which were reduced by heating in a thermogravimetric furnace to temperatures between 1273 and 1573 K under argon. The progress of the reaction was monitored by measuring the weight loss with time. The reduced compacts were found to have low strength in compression testing. The main form of bonding between the reduced ironsand particles …

Compare Pilot-Scale And Industry-Scale Models Of Pulverized Coal Combustion In An Ironmaking Blast Furnace, Yansong Shen, Aibing Yu, Paul Zulli

Faculty of Engineering and Information Sciences - Papers: Part A

In order to understand the complex phenomena of pulverized coal injection (PCI) process in blast furnace (BF), mathematical models have been developed at different scales: pilot-scale model of coal combustion and industry-scale model (in-furnace model) of coal/coke combustion in a real BF respectively. This paper compares these PCI models in aspects of model developments and model capability. The model development is discussed in terms of model formulation, their new features and geometry/regions considered. The model capability is then discussed in terms of main findings followed by the model evaluation on their advantages and limitations. It is indicated that these PCI …

Slides: Unido: Partner For Prosperity, Kandeh K. Yumkella

2012 Energy Justice Conference and Technology Exposition (September 17-18)

Presenter: Dr. Kandeh Yumkella, Chairman, UN Energy; Director General, United Nations Industrial Development Organization (UNIDO)

16 slides

Agenda: A Low-Carbon Energy Blueprint For The American West, University Of Colorado Boulder. Natural Resources Law Center, University Of Colorado Boulder. Renewable And Sustainable Energy Institute, Western Resource Advocates, Rocky Mountain Research Station (Fort Collins, Colo.)

A Low-Carbon Energy Blueprint for the American West (Martz Summer Conference, June 6-8)

The future of the planet may depend upon our ability to increase energy supplies even as we reduce carbon emissions. This conference will address how a low-carbon energy program might evolve with a particular focus on the American West. It will focus on the future of energy in the West--on a “managed transition” to a different energy mix, on the need to nest this effort in a framework that acknowledges interconnections, and on identifying the most salient opportunities to consider the legal, political, financial, and technical challenges.

Underground Coal Mine Delay Data Analysis System, Ernest Y. Baafi, Ian Porter

Faculty of Engineering and Information Sciences - Papers: Part A

Due to the high levels of uncertainty in underground coal mining operations, delays occur regularly which inadvertently reduce the utilisation of mining equipment. In most coal mines delay data is primarily sourced from shift reports, machine monitoring and production systems. The recording process is initiated commonly at the end of a shift to ensure the correct information is recorded for the managerial decision process. An issue that the Australian coal industry faces is the lack of a standardised delay recording process and delay classification system. Tools used within the industry to analyse delay data are mostly mine specific and offer …

Enhanced Gas Drainage From Undersaturated Coal Bed Methane Reservoirs, Dennis John Black, Naj Aziz, Ting Ren

Faculty of Engineering and Information Sciences - Papers: Part A

Traditional methods of coal seam gas drainage rely on the use of reservoir pressure reduction to promote gas desorption from the coal matrix. Studies in coal mining gas drainage operations, particularly in coal seams that are deeply undersaturated and have low permeability, found the rate of reservoir pressure reduction was prohibitively slow. In such conditions, lengthy production delays have been experienced while additional gas drainage drilling is undertaken in an attempt to reduce seam gas content below specified threshold limits. Such drilling represents a high additional operating cost and yields low total gas production whilst adversely impacting the mine's gas …

Slides: The Here And Now Of U.S. Nat Gas, Michelle Michot Foss

Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)

Presenter: Michelle Michot Foss, Chief Energy Economist, Center for Energy Economics, Bureau of Economic Geology, University of Texas, Austin, TX

12 slides

Slides: Impacts Of Oil Shale On Carbon Emissions, Jeremy Boak

The Promise and Peril of Oil Shale Development (February 5)

Presenter: Dr. Jeremy Boak, Center for Oil Shale Technology & Research, Colorado School of Mines

43 slides