Roller Press
1. Preface to Roller Press
Since the 1980s, with the deepening research of material crushing mechanism and analytical methods, two crushing methods, such as impact crushing and press grinding, have appeared in mechanical force crushing, and various new grinding equipment developed from this has developed rapidly.
Grinding equipment mainly based on moving roller extrusion and grinding have become representative equipment with high output and low energy consumption. In addition, typical equipment, such as Japan's Leicher vertical roller mill and Germany's MPS roller mill, both rely on the grinding force between the grinding roller and the grinding disc to crush materials except for the different shapes of the grinding rollers. The crushing function is higher than that of the ball (tube) mill, which can save 1 time of power consumption, has a large grinding particle size, adapts to materials with high water content, can produce products with different particle sizes by adjusting roller pressure, and has low noise. It is considered as an advanced crushing and grinding equipment in contemporary times. However, the equipment has a complex structure, high cost, great wear between grinding roller and grinding disc, and complicated maintenance and replacement of grinding roller. At the same time, the products of the vertical roller mill are discharged and packed by high-speed airflow (70 ~ 80m/s), which leads to the high resistance of the mill, especially when the product particle size is large, which consumes part of energy accordingly. Therefore, this kind of crushing and grinding machine-high pressure roller press, which has the same principle and similar process and can overcome the above shortcomings, has been widely developed and applied.
2. Working Principle and Structure of Roller Press
The crushing mechanism of high-pressure roller press is the crushing between particles. Materials are fed by an upper silo or spiral feeding mechanism, and two parallel and relatively rotating rollers bring materials in. The rollers are pressed into cakes with different compactness and a large number of cracks in the interior, or cakes and loose particles coexist. This kind of cake-like material is easy to be broken due to the existence of a large number of cracks inside, and the broken particles or powder are also easy to be ground.
3. Application of Roller Press
The main technical parameters of a small high-pressure roller press are: the diameter of the roller is 36520mm, the total installed power is 37kW, and the oil pressure is adjustable from 0 to 25 MPa.
Compared with the closed-circuit process composed of a double-roll crusher and hammer crusher, the high-pressure roller press is very convenient for producing materials with different particle sizes because of its adjustable oil pressure. Especially for materials less than 2mm, the productivity is increased by more than 4 times, the energy is saved by more than 50%, and the consumption of wearing parts is low. It is suitable for preparing fine particles or fine powders of most refractories such as magnesia, vanadium soil, mullite, silicon, spinel, and high alumina products, or as pre-crushing feed before fine grinding.
