1. Solid Dense Phase - Very low material velocity, pipeline full of material - an excellent regime for fragile materials.
2. Discontinuous Dense Phase - Low material velocity - with high line loading ... material moves in plug flow fashion - best regime for most applications in which power economy, pipe erosion, and material degradation issues are important.
3. Continuous Dense Phase (Moving Bed) - Higher velocity than discontinuous dense phase, but much lower than dilute phase. Used for handling powders that can be fluidized.
4. Dilute Phase - Material velocity above the saltation velocity - no upper limit to the velocity - least attractive regime for operating economy - unsuitable for fragile or abrasive materials or materials with wide particle size distribution.
