The process of reducing particulate materials from the coarse feed sizes to fine grind sizes for end use is called comminution. This is done by various process industries such as mineral, pharmaceuticals, pigment materials, ceramics, coal, cement, agricultural products, and so on. In the entire comminution process, grinding is the most energy-intensive stage, particularly for ultra-fine grinding, to produce appropriate fine size of final product. Producing super fine grind particles even below micron-sizes require enormous amount of energy. Therefore, the key efforts of recent comminution mill developments in grinding technology of different materials focus on increasing throughput and lowering energy consumption.
The trend towards fine and ultra-fine particulate materials with higher surface areas calls for more exacting requirements on the classification systems. As the cut size is further reduced, classification becomes more difficult and so significant efforts have been made in developing and using new air classifiers. The grinding process is further assisted by the application of thermal, chemical, or ultrasonic energies. These techniques have considerably contributed to the accomplishment of lower energy consumption in processing fine grind products. They also increase grinding energy efficiency by preventing agglomerates, improving rheonology of flow of material, and bringing down limitations of grinding.
Additionally, optimisation and control of production in grinding chamber and process have enabled the targeted quality of the final product. This can be achieved in several ways. One way is incorporating an online measurement system such as particle size analysis for ongoing control of grinding circuits which are known for their instability and unnecessary fluctuations, leading to inefficiency and poor extraction of minerals. Another option is utilising a computer simulator showing correct models for analysis and optimisation of a grinding mill and process. Each option varies but both are aimed at reducing energy consumption without adversely affecting the operation efficiency and throughput of producing fine grind products.