Performance Information

Pulse Dryer Performance

Pulse combustion spray drying is superior to conventional spray drying in many ways and for many reasons. This page describes some of the practical performance benefits and considerations of pulse drying.

Successful Materials
We have experience with over 170 different materials in our dryer, and have obtained very favorable results on minerals, specialty chemicals, foods and nutriceuticals.

For minerals, our powders are generally superior to spray dried powders in:

• particle surface characteristics
• mean particle size
• particle size distribution

For foods and nutriceuticals, our powders are generally superior in:

• flavor
• texture
• pigmentation
• protein viability
• surface characteristics
• flowability
• reconstitution properties
• particle size distribution.

For most materials currently spray dried, the PCS Dryer can handle the same feed in a higher concentration of solids. This yields higher powder production rates and lower processing costs per finished pound.

Special Materials
We have made successful powders with many difficult or 'undryable' materials.

The low degradation in the pulse drying process contributes to better taste and color of food products. This also produces similar benefits in other sensitive products. There are three reasons for this.

Firstly, the liquid is evaporated very rapidly by using high temperatures for a very short time. The heat transfer in the atomizing zone of the dryer is very high, and evaporative cooling protects the feed material. We have demonstrated that we can dry egg whites and other delicate proteins at 1000 F, without damaging them at all.

Secondly, no shear is applied to the liquid. The PCS Dryer does not use high-pressure pumps, nozzles or rotary disks. The liquid, slurry, or paste is fed at low pressure (~1psi) and atomization occurs in the exhaust jet of the pulse combustion burner.

Lastly, the hot, high-velocity combustor exhaust that comes into direct contact with the liquid contains less oxygen than a conventional spray dryer's heated air.

Problem Materials
While we are adding to our list of successful tests on often a weekly basis, we've also discovered a few materials that do not perform well in our dryer. These are products that have:

• High elastomeric viscosity,
• High levels of low-melting-point sugars, such as orange juice, or
• High levels of unencapsulated fat.