REGULATORY CONTROL OF A PILOT ROTARY KILN FOR ACTIVATED CARBON PRODUCTION

The design of a regulatory control strategy for a pilot rotary kiln to produce activated carbon is presented. A complex dynamic behavior with high non-linearity and an important dead time characterizes the rotary kiln operation. The main control objective of the process is to maintain the solid temperature profile inside of a narrow limit in order to produce an activated carbon with acceptable adsorbent properties. The manipulated variables are the temperature and the mass flow rate of the heating gas. The control scheme proposed consists of a conventional PID controller with Smith predictor in order to compensate the time delay. The control scheme is tested by means of simulation with a dynamic model previously developed in Matlab. The results are satisfactory and constitute a reference point to develop other advanced control strategies.