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The rapid growth of prices for sulfur in 2008 and their subsequent reduction are not the first case in the world practice.
In particular, in the end of 1970s in Canada about 20 million tons of sulfur remained in storage because of the low prices.
After the market price of sulfur grew to 120 USD, all the sulfur produced and accumulated over that period was sold in 2 years.
Over the period of the price explosion in 2008 Canada also sold all the accumulated sulfur.
According to the data of the annual international sulfur conference, there are about 10 million tons of net sulfur in the
world. With a view to the increased sulfur production and processing of sulfur oils and gas condensate materials, as well as
to the more thorough refinement of oil products, sulfur surplus will continue to grow. In this connection there is a growing
necessity of development of ecologically safe variants of the long-term storage of sulfur.
When sulfur is stored on open concrete grounds, the atmospheric motion causes sulfate corrosion of the ground.
The existing concrete surfaces for open storage of sulfur are subject to destruction. Sulfur acid leaks through concrete,
which leads to pollution of soil and ground waters. Moreover, at open storage of sulfur it sublimates to the atmosphere
(about 5, 6 g per 1m2 per day at 20°Ñ, which makes more than 1 ton per day or more than 400 tons per storage upon the
condition that sulfur is stored in blocks).
Solar radiation increases sublimating and at storage of sulfur in the form of grains or in lumps, because
evaporation surface area increases. Open sulfur storage leads to its weathering and wastage under the influence of weather
conditions. At certain favorable conditions (presence of oxygen and water) biological corrosion (destruction) of sulfur
occurs, which leads to losses of sulfur. At long-term open storage of sulfur, the abovementioned factors lead to
ecological disbalance of the environment.
«Engineering» Ltd. offers the most ecologically safe method of the long-term sulfur storage.
To meet ecological requirements and to preserve sulfur, it is suggested to make the sulfur storage from sulfur concrete.
Ïîñëåäíèé ïðåäñòàâëÿåò ñîáîé ïëîòíûé ïðàêòè÷åñêè âîäîíåïðîíèöàåìûé ìàòåðèàë, óñòîé÷èâûé ê
àãðåññèâíûì ñðåäàì. Sulfur concrete is a firm, nearly waterproof material resistant to aggressive environments. Limestone,
dolomitic and granite macadam are used for preparation of sulfur concrete. The suggestion to store sulfur in a so-called
protective envelope from sulfur concrete will allow to reduce weathering of sulfur and sulfur compounds.
The sulfur storage can be performed in two ways:
1. Semihardened storage (depth of the storage depends on the level of ground waters).
2. Non-hardened storage.
Walls of the storage are built up with increase of the sulfur amount. When the storage is filled to the final grade,
the roof is isolated with plates made of sulfur concrete and the joint grounding is done with the help of liquid sulfur.
The storage (protective envelope) is done from sulfur concrete, which is a thermoplastic material. That’s why, at
liquidation of sulfur storages, sulfur concrete can be processed to usable products.
At present storages are formed in the form of in situ blocks by filling with liquid sulfur. In this case, when sulfur
is taken from the storage, it should be melted using the melting plant and brought into the market conditions (grains).
This way of sulfur storage leads to high energy expenditures and pollution.
«Engineering» Ltd. offers to fill the storage with small-grained sulfur produced right in the place of storage.
At such a way of the long-term storage (at certain market condition) it is possible to take and realize sulfur
rather quickly. Sulfur is taken by the pressure-pneumatic system. It is transferred by the existing transportation
resources (pullman cars, cement carriers), which is advantageous. This allows to avoid ecological problems arising
at transfer and storage of sulfur.
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