spraydryingut

A spray drying unit is an industrial equipment system that converts a liquid feed into a dry powder by atomizing the liquid into a hot drying gas, typically air. The liquid is pumped to an atomizer to form fine droplets, which rapidly lose moisture as they travel through a drying chamber. The resulting powder is then separated from the exhaust air in a cyclone or bag filter and collected in a receiver. The process is continuous and scalable, widely used for heat-treated powders.

Key components include a feed system, an atomizer (such as a two-fluid nozzle, a rotary atomizer, or a single-fluid nozzle), a drying chamber, a hot air supply system, and a product collection stage (cyclone and/or bag filter). The unit may also include heat exchangers to recover energy, and automation for controls and monitoring of temperatures, pressures, and flow rates.

Operational parameters determine product quality. Inlet air temperatures commonly range from 150 to 300 °C, with outlet temperatures adjusted to control moisture and product stability. Feed solids content, atomization method, and droplet size influence powder uniformity and flowability. Typical product particle sizes span tens of microns, and final moisture contents are usually low (a few percent or less).

Applications span food, dairy, beverage, and pharmaceutical industries, including milk powder, coffee, egg powder, flavors, and certain enzymes or pharmaceutical excipients. Advantages include rapid drying, strong powder uniformity, and high throughput; limitations involve high energy use, capital costs, and sensitivity to heat for some products. Design choices balance product properties, safety, hygiene, and regulatory requirements.