Humidity Control for Pneumatic Powder Conveying
Humidity / Moisture Control is a critical element for various forms of powders such as fine salt, detergents, flour, powdery foods, calcium phosphate, baking powder, wheat starch, plastics resin etc. Pneumatic conveying as a means of powder conveying system is widely used in many powder processing operations such as in handling transfer of food powders, flour in a mill, bakery or confectionery.
Due to the stickiness nature of the hygroscopic powders, they get stuck into nozzles, conveying belts and mixing machines leading to increased maintenance time and bad hygiene.
Stickiness – Powder gains properties of adhering or sticking to a surface and get stuck into conveying belts causing bad hygiene which ultimately leads to deteriorating of product quality.
Cluster formation – Due to excess moisture similar particles of powder gather closely together forming buildups inside the mixing machine and causing blockages in free flow of powder.
Lump formation – A large piece of powder sticks together without a definite shape causing obstruction in the nozzle passage and increasing the maintenance time.
Caking – Moist environment forces powder to change into a solid mass which leads to increase in product wastage and slowing down of production process.
Food powder processing
In order to retain quality of powdery foods, they need to be dried at low temperatures.
Applications Temperature (°C) Humidity (% RH)
Instant Coffee Processing 26 25
Flour 24 10
Starch 24 20
Gelatin 24 10-30
Milk Powder Storage 21-36 15-30
Confectionary-Chocolate Covering 21-32 45
Coffee Packaging 18 40
Dry Spice Conveying <48 12-16 Gr/Lb
Hygro Tech Engineers having a complete solution to treat the moisture problems with Hygro Dehumidifiers & drying chambers for all powder conveying, packing, storage