Method and apparatus for controlling a pelletizing operation.

摘要

A method and apparatus are disclosed for controlling the proportions in which dry particulate matter and liquid are added to a rotary pelletizer (107), so as to control the size of the pellets being produced. The depth of material on the tray of the pelletizer is measured at a particular position and the resulting signal is suitably smoothed and otherwise conditioned before being combined with a signal indicating either present liquid supply rate or present dry matter supply rate. The combined signal then being compared with a set point signal to generate an error or control signal which can be employed to control either the liquid flow rate or the dry matter flow rate. Since pellet size is related to the relative proportions of the liquid and dry matter flow rates to the pelletizer these forms of control enable control of the size of pellets produced, since the error or control signal can be arranged to influence this ratio in the direction appropriate to counter the effects which fluctuations of the measured variables would otherwise have upon pellet size.