Computational fluid dynamics simulations and experimental validation of tracer gas distribution in an experimental underground mine

Following a disaster in a mine, it is important to understand the state of the mine damage immediately with limited information. Computational fluid dynamics can be used to simulate and ascertain information about the state of ventilation controls inside a mine. This paper describes a simulation of tracer gas distribution in an experimental mine with the ventilation controls in various states. Tracer gas measurements were taken in the lab experimental apparatus, and used to validate the numerical model. The distribution of the tracer gas, together with the ventilation status, was analyzed to understand how the damage to the ventilation system related to the distribution of tracer gases. This study will be used in future research in real mine measurements to compare collected and simulated profiles and determine whether damage to the ventilation system has been incurred during an emergency situation, the nature of the damage and the general location of the damage

The first commercial coal bed methane project in Turkey - Reservoir simulation and prefeasibility study for the Amasra coalfield

This study plans and models coalbed methane (CBM) recovery from the Amasra coalfield (the east and the west fields) in Zonguldak Basin, Turkey and compares the results from several operational development scenarios in order to identify the most effective development strategy. The reservoir was modelled using GEM, an advanced general equation-of-state compositional simulator. Vertical and multi-lateral CBM development plans were proposed and the cumulative gas production and gas production rates were estimated. Finally, a standard discounted cash flow analysis was performed. It was found that the vertical and multi-lateral CBM plans would yield positive NPV's - US$12,148,498 (IRR - 28.35$ 11,250,167 (IRR - 27.39%) respectively - only at the west field. Financial analysis showed that none of the alternatives are feasible at the east field. It can be concluded that the vertical CBM development plan with higher IRR (28.35%) would be the best alternative for the west field considering the technical difficulties in drilling operations and much higher capital investment in the multi-lateral CBM development plan. By this way emissions of 2.57 MMtCO2e would be avoided over a 20-year period based on the fact that the coal will be mined and the resulting methane will be liberated. © 2016 Inderscience Enterprises Ltd

Computational fluid dynamics study of tracer gas dispersion in a mine after different ventilation damage scenarios

Tracer gases are an effective method for assessment of mine ventilation systems, but their dispersion characteristics can differ substantially as ventilation parameters, such as flow path and velocity, vary. This research utilizes Computational Fluid Dynamics (CFD) to model a simplified full scale model mine, details a sensitivity study examining mesh size for an underground coal mine simulation, and examines gas dispersion parameters to determine the optimal model methods for simulation of tracer gases in underground coal mines. These models can be used to determine how a given tracer gas profile might be generated in a mine or areas of a mine that are not accessible, for example, immediately following a mine disaster. Accurate simulation scenarios can allow for the remote determination of the status of the ventilation network, but the sensitivity of the simulation at mine scale must be carefully examined. Copyright © 2012 by SME

Effective utilization of tracer gas in characterization of underground mine ventilation networks

Tracer gases are an effective method for assessing mine ventilation systems, especially when other techniques are impractical. Based on previously completed laboratory and field experiments, this paper discusses some common and challenging issues encountered when using tracer gases in underground mines. The discussion includes tracer release methods, sampling and analysis techniques. Additionally, the use of CFD to optimize the design of tracer gas experiments is also presented. Finally, guidelines and recommendations are provided on the use of tracer gases in the characterization of underground mine ventilation networks. This work has informed the practical use of tracer gases in mines, and this body of knowledge is expected to contribute to more efficient and more common use of tracer gases by mine engineers, which will allow for better characterization of mine ventilation system and improved safety. The findings can also be used when using the tracer gas technique in the evaluation of atmospheric environment and air quality investigation in buildings

Computational fluid dynamics applied to mining engineering: a review

This paper provides a review of computational fluid dynamics (CFD) applications in mining engineering, with particular focus on mine ventilation-related flow problems. The basic principles of CFD are reviewed and six turbulence models commonly used are discussed with some examples of their application and guidelines on choosing an appropriate turbulence model. General modelling procedures are also provided with particular emphasis on mesh independence study and CFD validation methods, which can further improve the accuracy of a model. CFD applications in mining engineering research and design areas are reviewed, which illustrate the success of CFD and highlight challenging issues. It is expected that more CFD research will be carried out to solve problems in mining engineering, and the potential benefits from the simulations are enormous if proper modelling procedures are followed and modern computational approaches are implemented

Remote characterization of ventilation systems using tracer gas and CFDin an underground mine

Following an unexpected event in an underground mine, it is important to know the state of the mine immediately, in order to manage the situation effectively. Especially when part or the whole mine is inaccessible, remotely and quickly ascertaining the ventilation status is essential to mine personnel and rescue teams for making effective decisions. This study developed a methodology that combines tracer gas and CFD modeling to remotely analyze underground mine ventilation systems. The study was conducted in an underground mine with four different ventilation scenarios created intentionally for this study to simulate different ventilation damage scenarios. CFD models were built to simulate these ventilation scenarios and compared with the field experimental data to identify which scenarios had actually happened. The CFD model was also used to optimize tracer test parameters, guaranteeing that the status of a ventilation system can be identified more rapidly in an emergency situation. This work demonstrated that general determination of changes to a mine ventilation system is achievable through examination of tracer gas profiles and CFD modeling. Additionally, limitations of this approach are identified and discussed

Modeling of various degasification techniques: A case study from the amasra coal field, Turkey

Boren;DEMiR Export;et al;metso Expect results;Outotec;TMMOB Maden Muhendisleri Odasi23rd International Mining Congress and Exhibition of Turkey, IMCET 2013 -- 16 April 2013 through 19 April 2013 -- Antalya -- 105453The Zonguldak hardcoal basin, located on the Western Black Sea coast of Turkey, is the only hard coal basin in the country. The seams in the area are extremely gassy and coal mines have experienced a number of methane outbursts and explosions that have caused loss of life and property. In addition to the safety risk, methane emissions from the existing mines in the basin are a significant source of greenhouse gases (GHG) and their reduction and control is a major environmental concern. Therefore, extraction of methane from the coal seams in the basin can be a solution to both carbon management and safety performance, providing at the same time a clean energy source for the country. Developing methane recovery technologies, before and/or during the mining cycle, requires sound engineering practices to realize the environmental and safety benefits. The aim of this study, sponsored by the United States Environmental Protection Agency (USEPA), is to investigate various options for the capture of coal mine methane in Zonguldak basin. The Amasra coal field, which is located in the eastern part of the basin, was chosen as the study area since there are mining activities in the region both by public and private sector companies. Hema Enerji A.S, a private company, has been developing a new underground coal mine in the region and the modeled coal seam in this study pertains to one of the panels under development by the company. The coal seam is at -420 m level and its thickness is around 4 m. An advanced general equation-of-state compositional simulator, Computer Modeling Group's GEM, was used to model methane capturing options, including pre-mining and mine level degasification techniques for methane recovery. The results will help to determine the most effective degasification techniques for this particular area