Coal pipelines are
pipelines
A pipeline is a system of pipes for long-distance transportation of a liquid or gas, typically to a market area for consumption. The latest data from 2014 gives a total of slightly less than of pipeline in 120 countries around the world. The Un ...
used to transport
coal
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other Chemical element, elements, chiefly hydrogen, sulfur, oxygen, and nitrogen.
Coal i ...
from where it is
mined to where it is consumed. For very short distances, large trucks are used to transport coal, but
train
A train (from Old French , from Latin">-4; we might wonder whether there's a point at which it's appropriate to talk of the beginnings of French, that is, when it wa ... , from Latin , "to pull, to draw") is a series of connected vehicles th ...
s and
barge
A barge is typically a flat-bottomed boat, flat-bottomed vessel which does not have its own means of mechanical propulsion. Original use was on inland waterways, while modern use is on both inland and ocean, marine water environments. The firs ...
s 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
Rail transport (also known as train transport) is a means of transport using wheeled vehicles running in railway track, tracks, which usually consist of two parallel steel railway track, rails. Rail transport is one of the two primary means of ...
or
waterway
A waterway is any Navigability, navigable body of water. Broad distinctions are useful to avoid ambiguity, and disambiguation will be of varying importance depending on the nuance of the equivalent word in other ways. A first distinction is ...
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
Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known liv ...
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
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other Chemical element, elements, chiefly hydrogen, sulfur, oxygen, and nitrogen.
Coal i ...
must be dried after it arrives at the
coal power plant. Coal transported as slurry requires a lot of drying and
electricity
Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...
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. A high concentration of the evaporating substance in the surrounding gas significantly slows down evaporation, such as when hum ...
d or separated in a
centrifuge
A centrifuge is a device that uses centrifugal force to subject a specimen to a specified constant force - for example, to separate various components of a fluid. This is achieved by spinning the fluid at high speed within a container, thereby ...
.
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
Aridity is the condition of geographical regions which make up approximately 43% of total global available land area, characterized by low annual precipitation, increased temperatures, and limited water availability.Perez-Aguilar, L. Y., Plata ...
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 list of regions of the United States, region of the United States that includes Arizona and New Mexico, along with adjacen ...
. 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
Laughlin () is an unincorporated community in Clark County, Nevada, United States. Laughlin lies south of Las Vegas, in the far southern tip of Nevada. As a resort town, it is known for its gaming and water recreation. As of the 2020 census, t ...
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
Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...
. 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
Coal-water slurry fuel is a mixture of fine coal particles suspension (chemistry), suspended in water. Such slurries are used to transport coal. Typically, the slurry is dried prior to combustion.
In principle but not in practice, coal slurrie ...
References
{{reflist
External links
Coal Log Fuel Pipeline Transportation System(PDF)
‘Two scenarios' for facility's future
Pipeline
A pipeline is a system of Pipe (fluid conveyance), pipes for long-distance transportation of a liquid or gas, typically to a market area for consumption. The latest data from 2014 gives a total of slightly less than of pipeline in 120 countries ...
Power station technology
Pipeline transport