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Dieren en planten

Water en land

Mens en Milieu

Pollution   Sulfur   

Sulfur

Sulfur compounds play a role in the environment mostly in the form of acidic sulfuric oxides (SO2). SO2 often develops during the burning of sulfur-holding oil and coal, for example, at power stations and in ship motors. Natural gas can also contain sulfur. However, it is removed before it is combusted. In order to fight acidification of the environment, most modern incineration plants on land are equipped with desulfurizing machinery. For shipping, the solution lies in the use of sulfur-poor fuels.

  • Acid rain

    SO2 is one of the materials which plays a role in the problems of acidification. Many plant species have problems when they are exposed to too many acidic materials. Lichens, in particular, are extremely sensitive to acidification. In the 1980s, there was great alarm concerning acid rain. Consequently, decreasing the emission of sulfur in industry and road traffic was rapidly dealt with. Emission from shipping was not included, so that the amount of SO2 emission from ships is relatively much greater.
    SO2 emission is caused by the sulfur in shipping fuel (bunker oil). Sulfur levels in bunker oil fluctuates considerably. The worldwide average is around 3.5% and the sulfur level  in oil that is tanked around the North Sea averages 2.5%. Sulfur-poor bunker oil is more expensive than regular bunker oil.

  • Sulfur -free

    As far as production technique is concerned, gas oil can be readily made sulfur-free for inland shipping. Besides removing the sulfur, it can be accomplished by adding lesser amounts of oil and more amounts of bio-fuels and oil from coal and natural gas. Having ships run on other types of fuels than gas oil is not yet possible in the near future.
    In the Annex VI of the Marpol Treaty, standards have been set for the maximum levels of sulfur allowed in fuels for shipping. The world-wide standard for SOx is 4.5%, however in Sulfur Emission Control Areas' (regions where the need to decrease sulfur emission extra great is), ships may only motor with bunker oil containing 1.5% sulfur at the most, or with an exhaust which is provided with a de-sulfurizing installation. Annex VI came into force in 2005 and the Baltic Sea and the North Sea have receieved the status of a Sulfur Emission Control Area.