Fertiliser application is necessary to meet the demands of the world’s population, in supporting the growth of healthy crops and maximising the efficient use of land.
However, for the majority of our fertiliser needs, nature has provided us with the raw materials but not necessarily in the composition that we want, or in the form that we can use.
The reduction of particle size is a fundamental requirement for an efficient mining and processing operation, but also forms a key stage within the majority of fertiliser production processes. The selection and application of size reduction and screening technology will impact the economics of the business and directly influences fertiliser finished product quality.
Size reduction falls into two categories:
1. Compression, where the material is compressed until it breaks.
2. Impacting, which uses the principle of quick impact to reduce size.
The physical properties of the material will influence the size reduction technology and also the sizing technology required. The finished product specification in terms of size and shape is directly influenced by the technology that is chosen.
A multitude of screening technologies is available but they differ in many cases on the mode of vibration. The screen must be reliable, accurate and represent a good return for invested capital. The ideal screener for a process is one that is the most efficient at recovering product sized material.
The fertiliser sizing journey to finished product, can be complex, but the key criterion is understanding the physical properties of the material, and matching the technology selection to those properties.