SPONTANEOUS COMBUSTION OF LIGNITE IN BARDH MIRASH MINES IN KOSOVO

9th International Multidisciplinary Scientific GeoConference - SGEM2009, www.sgem.org, SGEM2009 Conference Proceedings/ ISBN 10: 954-91818-1-2, June 14-19, 2009, Vol. 1, 121-128 pp

ABSTRACT

Kosovo is rich in coal resources / reserves. There are about 14 billion tones coal
resources in Kosova. The coal in Kosova is used mainly in power (electricity)
generation and less amount for heating. Kosovo coal is lignite type.

Exploitation of coal is being donning in two open pits Bardh and Mirash. There is also a
project for building of the new power plant (capacity 2000 MW). For this, supply of
coal should be made by the new mine - Sibovci.

The underground mining was abandoned in 1922. Now it is the surface mining or
opencast mining.

During mining of coal, is very present self combustion.

Oxygen is absorbed on to the surface of the coal causing exothermic reaction, which is
the start of oxidation. One direct side-effect of oxidation is that of spontaneous
combustion. This occurs when the rate of heat generation by oxidation exceeds the rate
of heat dissipation. All coals have the propensity to heat spontaneously, but lower rank
coals have a greater tendency to self-heat. The propensity to spontaneous combustion is
related to the rank, moisture content and size of the coal. In addition, mining and
ventilation practices and geological conditions can also be contributory factors.

Self combustion of coal in Kosovo coal mines, especially occurs in: old galleries from
the early underground coal mining; slide areas; slopes (especially the central pillar parts
of the mine which remain exposed to air for a longer period), faults and joints. Self
combustion also occurs in dumped coal masses.

Self-ignition of coal effects on: directly in the mine through release of smoke and gases
that contain SO2, CO, CO2, and NOx; stability of the mining equipment if found in the
coal basement who exhibited oxidation for a long time; reduction of coal reserves in the
area of self-ignition; delayed of coal exploitation.

Prevention of coal fires means to avoid contact of coal and oxygen. The main focus is
on the avoiding of oxygen entry into the underground corridors. This can be done by
means of: protection of cut old galleries against ventilation; Inspections of collapsed old
galleries near the surface or shafts if oxygen can penetrate somewhere and where
appropriate, refilling of openings; minimising a permanent contact of the coal with atmospheric oxygen (e.g. covering or sealing of slide faults); reducing the time of
exposition of the excavation front.

Keywords: coal, oxidation, spontaneous combustion, exothermic reaction, coal fires