MAC Dense Phase Batch Pneumatic Conveying
Dense Phase Theory
Dense phase pneumatic conveying systems operate below the minimum suspension velocity and are characterized by product moving along the bottom of the pipe in slugs or a moving bed. Product is conveyed below its saltation velocity at high differential pressures. Conveying velocities are typically less than 2600 FPM and material to air ratios of up to 100 to 1 are possible. Interaction of the particles in a dense phase system is greater than in dilute phase systems.
Commonly Conveyed Products
Common applications for dense phase systems include products with heavy bulk-densities, abrasive products, friable products, blended products and in some instances products that do not require continuous delivery to their destination. In many cases, the product needs to be evaluated based on process needs and possibly lab tested prior to final system selection to ensure the desired results can be achieved. Lab testing will also allow the product properties to be evaluated.
System Design
Pressure vessel systems are the most common dense phase system. MAC's innovative Continuous Dense Phase (CDP) and Low Pressure Continuous Dense Phase offer other dense phase options. Single vessel systems typically will operate in four distinct cycles:
Dual vessel systems can be configured to operate in a semi-continuous dense phase manner where the first vessel loads with product while the second vessel conveys the product. The motive gas typically will be compressed air with system pressures operating up to 80 PSIG. Due to this the vessels need to be ASME Code stamped.
