Page 322 - Advanced Mine Ventilation

Gas Transport in Underground 18

Coal Mines

Chapter Outline

18.1 Construction of Pipeline 300
18.1.1 Pipeline Material 300
18.1.2 Fitting/Couplings on the Pipeline 300
18.2 Gas Leakage Detection and Safeguards 302
18.2.1 Instrumentation for Detecting Leaks and Ruptures 303
18.2.1.1 Methane Detectors 303
18.2.1.2 Sonic Leak Detectors 303
18.2.1.3 Oxygen Detectors 303
18.3 Other Preventive Measures for Safe Gas Transport 303
18.3.1 Automatic Shut-Off Valves 303
18.3.2 Sectionalization of the Pipeline 304
18.3.3 Water Traps on the Pipeline 304
18.3.4 Flame Arrestors 304
18.3.4.1 Some Useful Guidelines 305
18.3.4.2 Discharge From the Pipeline 306
18.4 Ventilation 306
18.5 Corrosion of Steel Pipelines for Methane Drainage 306
18.5.1 Protection Against Corrosion 307
18.5.2 Cathodic Protection 308
18.6 Compressors 309
18.7 Surface Discharge of Gas 309
18.8 A Typical Application for Mine Safety and Health Administration Approval of
a Gas Pipeline System 310
References 312

A growing number of coal mines are degasifying coal seams prior to mining. It is
strongly advocated for moderately gassy and highly gassy coal seams. The produced
gas, of necessity, has to be transported outside the mine without mixing it with mine
air. In successful projects, often, more than 1 MMCFD of gas is carried in these pipe-
lines. It raises many safety concerns about leakage of gas that can create an explosive
atmosphere. The subject was thoroughly researched by Thakur [1] in collaboration
with Mine Safety and Health Administration of the United States [2]. The subject is
divided into three parts to address the safety issues properly:

1. Construction of pipeline and safeguards against potential damage.
2. Gas leakage detection and safeguards.
3. Other preventive measures for safe gas transport.

Advanced Mine Ventilation. https://doi.org/10.1016/B978-0-08-100457-9.00018-3
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