FRUITS OF THE EARTHGIVING NATURE A HELPING HAND TO FEED FUTURE GENERATIONS.
Tessenderlo Group is an international chemicals company employing more than 7000 people in over 22 countries worldwide. The group’s Inorganic Chemicals division is a major manufacturer of potassium sulphate fertiliser and has an annual production capacity of 750,000 tonnes of sulphate of potash (SOP). Joseph Altham interviewed Dr Nicolas White, the group’s Marketing Director for Fertilisers, to find out why Tessenderlo believes there are new areas of opportunity for its water-soluble SOP products.
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agriculture, potassium and sulphur are essential nutrients for promoting plant growth. Tessenderlo is one of the world’s most important producers of potassium sulphate fertiliser, commonly known as sulphate of potash (SOP). Its plant at Ham in Belgium has an annual production capacity of 650,000 tonnes. The factory has been making SOP since 1926, employing the Mannheim process. This process involves a chemical reaction at a high temperature between potassium chloride and sulphuric acid, and the plant at Ham is the largest in the world to use this process. The Mannheim furnaces at Ham are particularly well adapted to producing high quality water-soluble SOP. Across the border, Tessenderlo also manufactures SOP at its French site in Loos, which has an annual production capacity of 100,000 tonnes. The key advantages of SOP as a fertiliser are that it is virtually chloride-free and has a very low salinity index. Certain crops, like strawberries, lettuce and tobacco, have a poor chloride tolerance, meaning that too
much chloride in the soil will have a bad effect on their quality. For crops like these, SOP is a much gentler source of potassium than alternatives such as muriate of potash (MOP). Salinity is a particularly serious issue in the semi-arid climates where there is not enough rainfall to wash the salt away. Here, the wrong type of fertiliser can ruin the soil, as Dr White explained. “If chloride and salt accumulate, this can poison the soil. In one case in Jordan, repeated use of potassium chloride as a fertiliser for potatoes eventually turned the soil white. In soils at risk from salinity, sulphate of potash is the best product to use because among the main potash fertilisers it is the one with by far the lowest salt index.”
A global business Tessenderlo offers three different types of SOP. The company’s standard powder SOP is widely sold to manufacturers as a raw material for making compound fertilisers. The group also produces SOP in granular form branded as GranuPotasse®. Granu-
