Fugitive dust generated during the normal handling of granular fertilizer products has been a problem for both manufacturers and those selling the fertilizer products. An early commonly used solution for this problem was to coat the fertilizer granules with petroleum oils. This proved highly effective in suppressing dust at the manufacturing and shipping location. This treatment tends to lose its effectiveness if the treated material is stored for long periods after treatment. This loss of effectiveness has been attributed to the fact that the oil used to coat the particles is absorbed into the particles and no longer acts as a surface coating.
To adequately address this problem this project had to first develop a satisfactory method to accurately measure the amount of dust generated. Once this technique was proven, it was possible to rapidly measure the dust generation characteristics of a fertilizer product and determine the effectiveness of the various dust suppression agents available for this purpose.
While the study did not determine how to manufacture granular fertilizers that would not dust, it did evaluate a number of dust suppression agents and conducted plant scale tests to demonstrate the effectiveness of the best coating agents tested. The testing procedure developed can be used to screen new dust suppression agents in a simple and economical manner.
Dale A. Lundgren and Cumbum N. Rangaraj, University of Florida. March 1989.