March 2016
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World Coal
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61
W
ithout bulk materials, the world economy
could not exist. From production to final
usage, all bulk materials must be stored,
reclaimed from storage and transported a
number of times. In fact, the cost of handling bulk materials is,
for a large number of materials, a significant part of the total
cost of the bulk material by the time it reaches the final
consumer. Handling many bulk materials can be detrimental to
the environment. Other bulk materials, to protect their value,
must be protected from the environment. The challenge to an
engineer charged with the responsibility of designing systems
to transport, store and reclaim bulk materials can therefore be
viewed as finding the most economical method of transporting,
storing and reclaiming those materials, while minimising the
effect of the materials, on the environment and minimising the
effect of the environment on those materials.
The transport of break materials was greatly facilitated with
the invention of the intermodal container. Safety of the
materials was greatly increased, cost of transport was
drastically decreased and the world economy (China, Walmart,
etc.) was greatly benefitted. If only a method of handling bulk
materials that had the same effect could be found, since bulk
materials are usually rawmaterials, a similar effect on the
world economy could be expected.
Stages to storage
Bulk materials typically are produced at a rate that differs from
the rate at which they are shipped or consumed. Corn is
harvested in a short time period. The harvest rate is much
greater than the shipping capability of the industry. Many ores
are produced at a rate different from the processing rate and
the ore produced in days is often loaded into trains for
shipping in two to four hours. The corn, while waiting to be
shipped needs be protected from the environment and the ore,
while being processed and awaiting shipment can be a threat to
the environment.
Each stage of storage and reclaim increases the product cost.
To protect the corn requires storage silos and the attendant
loading and unloading systems. When all silos are full and the
crop has yet to be harvested, outside storage is sometimes used
with varying degrees of success. Coal (and other minerals) are
often stored before processing so as not to link mine operation
to plant operation. Processed coal (and other materials) must be
stored to ensure that when the train arrives to transport the
material, sufficient material is available to load the train in the
requisite time.
If the bulk material is to be transported by barge or ship,
large stockpiles can be required to prevent delays in loading the
barges and ships. Unfortunately, many good harbours are
