E-Book, Englisch, 186 Seiten, eBook
Dhillon Mine Safety
1. Auflage 2010
ISBN: 978-1-84996-115-8
Verlag: Springer
Format: PDF
Kopierschutz: 1 - PDF Watermark
A Modern Approach
E-Book, Englisch, 186 Seiten, eBook
Reihe: Springer Series in Realibility Engineering
ISBN: 978-1-84996-115-8
Verlag: Springer
Format: PDF
Kopierschutz: 1 - PDF Watermark
Zielgruppe
Professional/practitioner
Autoren/Hrsg.
Weitere Infos & Material
Safety Mathematics and Basics.- Safety Management.- Safety Analysis Methods and Indices.- Global Mine Accidents.- Human Factors and Error in Mine Safety.- Mining Equipment Safety.- Electrical Accidents in Mines and Programmable Electronic Mining System Safety.- Gas-related, Fire, and Blasting Accidents in Mines and Methods for Determining Mine Atmosphere Status.- Safety in Offshore Industry.- Mathematical Models for Performing Safety Analysis in Mines.
"Chapter 9 Gas-related, Fire, and Blasting Accidents in Mines and Methods for Determining Mine Atmosphere Status (p. 111-112)
9.1 Introduction
Coal bed gas has been considered a major mine hazard since the first documented coal mine gas explosion in 1810 in the United States [1]. It has considerably affected safety and productivity in underground coal mines throughout the world. Fires are another major safety problem in mines. For example, there were over 7,700 fires during the period between 1947–2006 in underground hard coal mines in Poland alone [2]. Blasting is an important and hazardous element of mining and many serious injuries and fatalities result from improper judgment or practice during the blasting process.
During 1990–1999, approximately 22.3 billion kilograms of explosives were used by the mining, quarrying, construction, and other industrial sectors in the United States [3]. Samples of mine atmosphere are usually taken during normal operations to establish a reliable baseline. On the basis of these samples, mine operators can effectively determine changes in mine atmosphere. Furthermore, in the event of a firerelated emergency these samples become very useful in fire fighting operations, rescuing operations, etc. This chapter presents various important aspects of gasrelated, fire, and blasting accidents in mines and two important methods for determining mine atmosphere status.
9.2 Origin and Mechanism of Coal Mine Outbursts and Their Prediction and Prevention
It is commonly accepted that by virtue of their chemical and physical characteristics, rock aggregates in the earth’s crust are composed of a network of structures that include pores, fractures, and micro cracks filled with liquid and gaseous substances. Coal is one example of these rock aggregates that has accumulated gaseous substances such as methane, carbon dioxide, and/or nitrogen in these structures during the coalification process. Some of the direct or indirect causes identified for outbursts in underground coal mines are as follows [1]:
• The internal energy of the gas contained in the coal bed
• Gas pressure and quantity
• Rock pressure and strength
• Micro seismic activity propagated by reactivation of faults and explosives
• Maceral composition of the coal
Knowledge accumulated through investigations to determine the origin of coal bed gas and mechanisms of coal mine outbursts has played an instrumental role in enhancing outburst and explosion prediction and prevention methods. Prediction includes activities such as monitoring of gas emissions, monitoring of microseismic acoustic emissions, and monitoring of acoustic signal spectrum characteristics with respect to structures in the rock mass [1].
Some of the methods that can be used to prevent the occurrence of coal-mine outbursts are as follows [1]:
• Utilizing predicting methods. These methods can be used to control and prevent underground coal mine outbursts. For example, by taking gas content and pressure measurements from drill holes on the surface and subsurface, one can determine the threshold conditions for outburst occurrence.
• Modifying mining methods and machinery. This approach is concerned with the modification of the existing methods and machinery to take into consideration rock-mass stresses that could trigger coal bed gas outbursts from an advancing mine face.
• Adopting different methods for gas ventilation or drainage. Two examples of such methods are removing gas through vertical wells in advance of mining, and drilling vertical gob wells into the cave area behind the long wall panel. Finally, it should be noted that the application of the above methods can be useful to improve mine safety, efficiency of mine operations, and mine economics."