With Alpine High Pressure Roller Mill products are produced with a precipitous granule distribution. The high pressure roller crusher is also called roller crusher or roller press.
The significant difference of high pressure roller grinding compared with compaction is that the press forces between the rollers are lower because no new adhesive forces need to be created.
The mill feed is transported to the most narrow gap by the counter rotating rollers through friction effects. Both rollers are pressed against each other using hydraulics. This milling force is transferred to the mill feed. Through selective contact of the individual granules are created at extremely high inner tensions which lead to fractures.
The use of the optimal milling force leads to compact mills with extremely low energy requirements. Because only the outer particles of the material bed have contact with the surface of the rollers, milling that is almost contamination-free is possible.
High Pressure Roller Mills are used in the cases of medium-fine crushing of hard materials such as ceramics, minerals from 5 up to 9 on the Moh's hardness scale, metals and metal alloys. High Pressure Roller Mills are used in continuous operation or in a closed circuit with screening machines or classifiers.
The Mikro Atomizer® Air Classifying Mill uses air flow to convey materials to the grinding zone. Size reduction occurs when hammers fitted to the rotor impact particles at 4,000 to 8,000 RPMs. A deflective liner returns oversized particles to the hammer impact zone for further reduction. The ground materials are then conveyed to the classifier wheels which are mounted to the grinding rotor. Larger particles are rejected for regrinding as the desired particles are air conveyed by internal fan blades and exit the mill for collection.
The wet material is fed through customized feeding systems into the grinding and drying section of the dryer's main body. The grinding rotor disperses the wet material into very fine particles and the fine particles are fluidized in the grinding chamber by temperature-controlled, hot gas coming in from the air heater.
The hot air (or inert gas) can be heated up to 650 °C and as the wet product is dispersed, it is reduced in size in the bottom section of the dryer. The system is kept under a negative pressure by the exhaust fan and the surface area of the product is increased enormously so that water (or other solvents) is evaporated instantaneously.
The dry and fine particles are conveyed with the gas stream to the top section of the dryer where a separator classifies the particles by size. Then the particles pass the classifier at the set cut point and are conveyed with the exhaust air to a powder air separating system like the cyclone, cyclone filter or cyclone scrubbers.
The Micron Dryer flash dryer retains a fluidized bed of product in the drying chamber to ensure a low level of adhesion of wet material on the inside wall of the drying chamber. Moreover, process parameters like classifier speed and outlet temperature can be adapted to control moisture content and particle size of the end product.
Ultra fine regular end product - Due to its specially designed dispersion rotor, our flash dryers are able to produce ultra-fine powders in one step from suspensions, slurries, pastes and dough, filter cakes or wet powders.
High evaporation capacity - Due to the combination of high ?T with a good dispersion of the wet product in the air, our flash dryers can evaporate large quantities of liquids.
Compact design - Compared to other direct drying technologies, the flash dryer requires up to 50% less space.
Multi-purpose - Filter cake or slurry, in the same machine. Therefore with the Drymeister-H unlimited mechanical dewatering is possible previous to the final drying stage.
Easy access - Either for cleaning, inspection or maintenance inside the dryer, our flash dryers offers the best accessibility from the market, regardless which size.
Various systems available - Open, closed- and recycle system concepts.