Industrial dryers — no matter how effective they are in drying solid materials — are incapable of maintaining product target moisture content (MC) at the lowest level practicable when evaporative-load changes to the dryer occur. Why? One big reason is that most dryers are controlled using moisture-content data obtained too late to be effectively used in a control system. Long dead times (time to detect an evaporative-load disturbance entering the dryer) produce proportionally wider moisture-content variations.
What does this mean for most dryer operators? Lack of effective moisture-content control forces operators to run at lower target moisture-content levels to avoid producing wet product. This is a costly practice that results in less production, higher energy costs and poorer product quality.