Targeted inertization with flue gas injection in fully mechanized caving gob for residual coal spontaneous combustion prevention with CFD modeling

Based on the concept of cleaner production, the feasibility of application of the flue gas in mine mouth power to fire prevention and extinguishing in goaf was numerically studied by taking the mechanized caving mining face 11-214 of Caocun coal mine as the example. The heterogeneity porosity and multi-component gas transport equations were introduced into the mathematical model. The calculated results showed that the area of “spontaneous combustion zone” turn small obviously in goaf and the maximum width of “spontaneous combustion zone” in goaf decreased from 78m to 9.5m after injecting the flue gas. At the same time, the sink terms of oxygen consumption was formed in the port of gas injection. The migration law of flue gas showed that the numerical calculation of goaf should select the different computation model based on the judgment basis of Reynolds number. Through the continuous monitoring of the migration of flue gas at different locations in goaf, the reasonable parameters of flue gas injection was obtained for high efficient fire prevention .

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A Study on Preventing Spontaneous Combustion of Residual Coal in a Coal Mine Goaf

Journal of Geological Research ◽

10.1155/2015/712349 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

Yongjun Wang ◽

Xiaoming Zhang ◽

Yuichi Sugai ◽

Kyuro Sasaki

Keyword(s):

Spontaneous Combustion ◽

Mine Ventilation ◽

Ventilation Network ◽

Leakage Flow ◽

Coal Spontaneous Combustion ◽

Economical Method ◽

Long Period ◽

Simulation Results ◽

Spontaneous Combustion Of Coal ◽

Residual Coal

The effectiveness of grouting scheme has been simulated to prevent the coal spontaneous combustion at a goaf in Haizi Colliery, China. The colliery has been operated for long period over 27 years and has a complex ventilation network including airflow leakages which could possibly lead to the spontaneous combustion of coal at goafs. Firstly, the mine ventilation simulator MIVENA was used to analyze the mine ventilation network airflows to control airflows in and out of working faces and goafs. As the second approach, numerical simulations were carried by the simulator FLUENT in order to predict spontaneous combustion of residual coal with leakage flow in the #3205 goaf. It was cleared that the goaf can be divided into three zones based on oxygen concentration in the goaf area. Finally, the numerical simulation results show that the slurry grouting method is able to be an effective and economical method by reducing porosity in the goaf area to prevent spontaneous combustion of residual coal.

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3D CFD modeling of natural draft wet-cooling tower with flue gas injection

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2015.08.095 ◽

2015 ◽

Vol 91 ◽

pp. 824-833 ◽

Cited By ~ 25

Author(s):

Adam Klimanek ◽

Michał Cedzich ◽

Ryszard Białecki

Keyword(s):

Flue Gas ◽

Cooling Tower ◽

Gas Injection ◽

Cfd Modeling ◽

Natural Draft

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A CFD Modeling Method of Realistic Parameters for Predicting Easily Coal Spontaneous Combustion Zone Accurately in the Gob of Long wall Face

International Journal of Mining Science ◽

10.20431/2454-9460.0302004 ◽

2017 ◽

Vol 3 (2) ◽

Keyword(s):

Combustion Zone ◽

Spontaneous Combustion ◽

Modeling Method ◽

Cfd Modeling ◽

Coal Spontaneous Combustion

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Effect Analysis of Nitrogen Injection on the Variation of “Oxidation Zone” in Coal Mine Gob Based on Numerical Simulation

The Open Fuels & Energy Science Journal ◽

10.2174/1876973x01609010047 ◽

2016 ◽

Vol 9 (1) ◽

pp. 47-54

Author(s):

Jing Shen ◽

Mingran Chang

Keyword(s):

Numerical Simulation ◽

Coal Mine ◽

Heat Dissipation ◽

Spontaneous Combustion ◽

Oxidation Zone ◽

Effect Analysis ◽

Mine Fire ◽

Nitrogen Injection ◽

The Difference ◽

Residual Coal

One of the main reasons for coal mine fire is spontaneous combustion of residual coal in gob. As the difference of compaction degree of coal and rock, the underground gob can be considered as a porous medium and divided into “three zones” in accordance with the criteria. The “three zones” are “heat dissipation zone”, “oxidation zone” and “choking zone”, respectively. Temperature programming experiments are taken and numerical simulation with obtained experimental data is utilized to analyze the distribution of “three zones” in this paper. Different width and depth of “oxidation zone” are obtained when the inlet air velocity is changed. As the nitrogen injection has inhibition effect on spontaneous combustion of residual coal in gob, nitrogen is injected into the gob. The widths of “oxidation zone” are compared before and after nitrogen injection. And ultimately the optimum location and volume of nitrogen injection are found out.

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