Following WWII, countries focused on economic recovery and development, leading to increased demand for metal and mineral materials. This prompted the construction and expansion of large-scale ore processing plants, driving the development of larger equipment with high production capacity and lower investment and operational costs. However, there are limits to equipment size due to resource constraints and technological-economic factors. While the trend towards larger equipment was rapid in the 1960s and 1970s, it slowed down in the 1980s. Notably, larger ball mills have lower efficiency compared to crushing equipment.
Most crushing and grinding equipment originated in the 19th century and has demonstrated reliability but suffers from low efficiency and high energy consumption. In the early 1980s, the global economic crisis led to a downturn in the mining industry, necessitating efficiency-centered improvements. Attention was focused on the development and improvement of crushing and grinding equipment, resulting in the emergence of new and upgraded devices such as impact jaw crushers, ultra-fine mills, gearless cone crushers, various impact crushers, ring motor-driven mills, and tower mills.
In the improvement of traditional equipment and development of new devices, new technologies and materials were gradually introduced. Large rolling bearings were applied to crushing and grinding equipment, high-pressure oil suspension was used in main spindle bearings, wear-resistant polyvinyl chloride materials were applied to screen meshes for extended lifespan, high-strength metal materials were used in equipment components, rubber lining plates and magnetic linings were employed, and automation technology was integrated into equipment control.
The crushing and grinding processes consume significant energy and materials, prompting ongoing research into energy consumption patterns and ways to achieve energy efficiency and reduction. Selective grinding and the study of grinding media in ball mills have been explored to improve grinding efficiency. Various studies have been conducted around productivity enhancement, energy efficiency, and other objectives, leading to notable achievements.
Mechanical crushing methods still dominate, but they suffer from low energy conversion efficiency and inadequate product dissociation. Therefore, research on new crushing methods continues, including studies on electric heating, liquid-electric effects, and thermodynamic crushing methods. However, these studies are still in the early stages.