Control method for centrifugal thin film dryer

Abstract

Abstract PURPOSE:To dry liquid effectively by providing a plant state estimating means and a powdering threshold change forecasting means and making the decision of adequate treating flow rate and the number of revolutions of blades possible. CONSTITUTION:Heat transfer surface temp. measuring means 7-11, a plant state estimating means 23, and a powdering threshold change forecasting means 24 are provided, and from the results thereof, an actual powdering threshold is forecast and treating flow rate and the manipulated variable of the number of revolutions of blades are determined. Since the change in the powdering threshold can be accurately forecast by this, abnormality is prevented, safe operation can be accomplished. Since the treating flow rate can be maximized below the threshold value, the efficiency of treatment can be improved and since the number of revolutions of blades can be minimized above the threshold value, the abrasion of heat transfer surfaces and blades can be minimized and the life of apparatus can be extended. Here, 21 is a flow rate controller, 22 a controller for number of revolutions, 25 a powdering threshold forecasting means, and 26 a manipulated variable determining means.

Inventors

• 👤 Mitsuo Kinoshita
• 👤 Tetsuo Ito

Bibliographic Details