How it works and what it targets
Conventional compressed-air preparation involves compression and cooling. Where the equipment and material allow it, this route retains heat from first-stage compression and converts gas energy into jet motion. Temperature can also affect delamination of minerals with cleavage or weak bonding planes. Compare it with cooled-air milling at the same product specification.
Reference process steps
- 1Establish gas temperature/pressure and material thermal stability.
- 2Use hot jets for milling and classifier return for size control.
- 3Configure collection, cooling and moisture control for the discharge conditions.
Configuration and operating conditions
Minerals and special feeds
For mica, wollastonite and talc, examine the balance between size reduction and morphology. Silicon monoxide and high-softening-point pitch require thermal behaviour and temperature limits to be established before selecting a hot-gas configuration.
Energy boundary
Include compressor, classifier, collection and auxiliaries in comparisons, recording feed, final size and output. Report drying duty separately from milling energy.
Information needed for selection
Provide thermal stability, softening/phase-change information, moisture, target morphology and size, and gas conditions. Evaluate cooled processing first for heat-sensitive feeds.
Discuss selection inputsTrial and acceptance considerations
Measure specific energy, yield and moisture change on the same feed and product specification. An energy-saving percentage is not a fixed guarantee across materials.