Coal pipelines are
pipelines used to transport
coal from where it is
mined
Mined may refer to:
* Mined (text editor), a terminal-based text editor
* Mining, the extraction of valuable geological materials from the Earth
See also
* Mind (disambiguation)
* Mine (disambiguation)
Mine, mines, miners or mining may refer ...
to where it is consumed. For very short distances, large trucks are used to transport coal, but
trains and
barges are preferred for long distances. In some cases it is more economical to move the coal by pipeline than by train or barge. This can happen when there is no suitable
railway or
waterway to transport the coal, or when it must be moved very long distances.
There are two types of coal pipelines, slurry and log.
Slurry pipelines use a slurry of
water and
pulverized coal. The ratio of coal to water is about 1 to 1 by weight. Coal log pipelines use coal that has been compressed into logs with a diameter 5 to 10% less than the diameter of the pipeline and a length about twice the diameter of the pipeline.
[Hydraulic Transport of Coal in Combination With Oil Granulation / V.Biletsky // 8th International Conference on “Transport and Sedimentation of Solid Particles” 24–26 January 1995, Pragye, Czech Republic. D6-1 – D6-11.] The ratio of coal to water is about 3 or 4 to 1.
Coal needs a very low moisture content before it can be burned efficiently, so the
coal must be dried after it arrives at the
coal power plant. Coal transported as slurry requires a lot of drying and
electricity generation will be substantially less if it is not dried effectively. Coal logs do not require as much drying because they are tightly packed so they do not absorb much water, and any water originally in the coal is squeezed out during compression. To dry the coal, the water is
evaporate
Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gas phase. High concentration of the evaporating substance in the surrounding gas significantly slows down evaporation, such as when humidi ...
d or separated in a
centrifuge.
Large
coal power plants use large amounts of coal each day; enough to fill a hundred train coal cars carrying each. Water used to transport the coal is likewise significant, particularly in
arid regions like the
Southwestern United States
The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado, Ne ...
. Such a power plant would use about with a coal slurry pipeline or about with a coal log pipeline. This amounts to about per year respectively.
The
Mohave Generating Station in
Laughlin, Nevada had the longest coal slurry pipeline in the world at . From 1969 until 2005, the pipeline used of water per year to carry about of coal to the plant from the
Black Mesa Mine in the northeastern corner of
Arizona. The plant was shut down on December 31, 2005 because the controversial coal and water supply terms were being
renegotiated.
See also
*
Coal-water slurry fuel
References
{{reflist
External links
Coal Log Fuel Pipeline Transportation System(PDF)
‘Two scenarios' for facility's future
Pipeline
Power station technology
Pipeline transport