The question is often asked, “How can more capacity be gotten from our spray dryer?” Or, “What is the greatest amount of powder that this dryer can produce?” Optimization of a spray dryer most often means greater capacity, greater energy efficiency, and lower manpower input. Optimization is a complex and multifaceted goal that is best looked at in three ways. First, one can address the question from the standpoint of maximizing any single hour of production—that is, by maximizing inlet temperature, outlet temperature, feed temperature, feed solids, etc. This procedure

can be both theoretical and scientific.

The second way to address the problem is on a monthly basis. In a 30-day month, there are 720 hours during which a dryer can run. How many hours per month is it in fact running? How many hours per month are lost to clean in place (CIP)?

How many hours are lost to process-related problems such a plugging, build-up, etc.? In many cases, more production can be achieved by reducing downtime than by trying to operate each production hour close to the theoretical maximum.

The third, and often overlooked, approach is to maximize dryer production on an annual basis based on changes in ambient conditions. Spray dryers almost always run better in winter than in summer.

This has to do with the amount of moisture in the ambient air.

When the moisture in the ambient air is higher, less water can be evaporated in thespray-drying process.Because each optimization procedure has unique requirements, it is difficult to give one-size-fits-all answers. But if an operation is analyzed critically, if the right questions are asked and if clear methods are applied to find solutions, operations can be improved.