Munters offers dehumidification of the air for the drying process, thus providing constant dry inlet air to the spray dryer. The benefits for the spray drying process are numerous, and in fact, the same as most producers already experience during winter months, where the air in colder climates is already dry. With Munters desiccant dehumidifiers, dry winter conditions are maintained through summer and are also achievable in tropical climates.
In the spray drying process, the drying air is in direct contact with the product during the drying process. When the air is always of the same dryness, the spray drying process no longer changes with the weather. Now, it is easier to control the process and product quality, avoid product sticking and dryer fouling, reduce powder loss, and plant downtime is reduced to a minimum. Furthermore, the lower humidity allows for a much higher drying capacity because the dry inlet air has more capacity for moisture evaporated from the product.
Most powders are cooled after drying before conveying to storage and packing. This process is done by either pneumatic cooling or in fluid beds. In both processes, the dry powder is in direct contact with the air. Keeping air humidity at a fixed low level allows for sufficient product cooling and ensures the desired powder moisture level, as it avoids hygroscopic products to reabsorb moisture. As a result, powder caking and clogging are not likely to occur.