Keywords: blending, Ireland, economics, quality, segregation, plant.
Travis P. Hignett traced the origin of fertiliser blending to the U.S. State of Illinois, where during the 1940s pulverised Rock Phosphate was first mixed with Potassium Chloride and distributed in road vehicles equipped with limestone spreaders. By 1947, four blenders were operating in Illinois mixing and spreading crude mixes of ground Phosphate Rock, powdered Potash and Ammonium Sulphate. From this crude beginning, the practice of blending spread throughout the U.S. and different variations were adopted in many other countries helped along by a few key occurrences.
The first major factor was the development of the TVA drum granulation process in 1953. This was first commercialised in large NPK granulation plants, but was quickly applied to the production of granular phosphates suitable for bulk handling and blending. Large plants located adjacent to Phosphate deposits commenced production of granular triple Super-phosphate for distribution to the blenders. Granular Diammonium Phosphate (DAP) followed and this became a widely used blend material.
Nitrogen also became available from huge central plants, first in the shape of prilled Ammonium Nitrate and later Urea. The Potash Producers also moved to provide Potash of a size required by the Blenders.
The growing trend towards upgrading and sizing fertiliser nutrients at or near the source of the Raw Materials and shipping the product directly to the Blender located in the market place helped to promote the growth of blending in the U.S. and Canada. As the availability of these materials on the World Market increased and as Blending adds very little to the cost of bulk shipment, storage, handling, bagging and distribution the practice spread and was adapted to suit conditions in other developed countries, such as Japan, the U.K., Ireland, France as well as developing countries such as Brazil, Korea and Guatemala.
This paper traces briefly the history of blending in the U.S., the country of its birthplace, and shows how the practice was adopted and adapted to a completely different set of conditions in the Republic of Ireland.
T M Young, Grassland Fertilizers Ltd., Dublin, Ireland.
32 Pages, 14 Figures, 2 Tables, 12 References.