Geology Reference
In-Depth Information
China: coal fires
0
500 km
Xinjiang
N
Urumqi
Ningxia
Coalfield fire
Coal mine fire
Figure 6.1.1. Coal fires across China: provinces are outlined. Anthracite reserves are concentrated in the Xinjiang
and Ningxia Hui provinces (autonomous regions). Urumqi, capital city of Xinjiang, is one of the most polluted
cities in the world. Coalfield fires are surface fires in seams, some of which occur in open-pit mines. Coal mine
fires include underground and surface fires in government and private mines. Photo by Anupma Prakash, 2003,
with modifications.
people, have forced entire communities to abandon their homes and businesses, have destroyed floral and faunal
habitats, and are responsible for perilous land subsidence.
This chapter discloses the severity of the coal fires problem. The objectives of the analyses presented herein are to
describe the origin of coal fires and related gases, discuss some of the world
s most problematic coal fires and
associated environmental hazards, and briefly consider techniques used to combat these fires.
'
The Mining Hazard
A
lthough coal has been mined for over a thousand years as a heating and cooking fuel, large-scale mining,
necessary to support the industrial revolution, did not begin until the nineteenth century (World Coal Institute
(WCI), 2000). Since 1995, coal and oil reversed rankings, with oil overtaking coal as the primary resource for
energy consumption (US Department of Energy (DOE), 1995, p. 19; WCI, 2000). As long as coal is strip or deep
mined in order to stoke the electrical and steel fuel-hungry economies of industrialized and developing nations, the
potential for uncontrollable fire exists.
Origin of Coal Fires
Most coal mine-related fires are ignited by (1) mine-related activities such as cutting and welding, explosives and
electrical work, and smoking, which may ignite gases such as methane and hydrogen (Mine Safety and Health
Administration, 1996; Pennsylvania Department of Environmental Protection (PDEP), 2001a); (2) surface fires
transmitted to culm banks or coal seams by lightning, forest or bush fires, and burning trash (DeKok, 1986, p. 20;
Geissinger, 1990; Discover, 1999); and (3) spontaneous combustion induced either by coal fines, oil-soaked rags,
lumber, hay, or manure in culm banks or by exothermic oxidation reactions catalyzed by oxygen circulating
through coal seam joints (Jones and Scott, 1939; Anthony et al., 1977, p. 29; DOE, 1993; ITC, 2003). One such
oxidation reaction is (Limacher, 1963)
O
2
þ
H
2
O
→
FeSO
4
þ
H
2
SO
4
7
2
FeS
2
þ
