Simulation of system identification and decoupling control of rotary lime kiln system

Lime is an important smelting raw material for iron& steel plants. Most of large and medium-scale iron& steel enterprises have their own lime works for self-supply. Reasonable control for the lime kiln is significant to reduce energy consumption and improve the pass rate of lime quality. In this paper, the model described in literature is applied to simulate the actual operating conditions of rotary lime kiln. The method of step response is adopted to identify the object with two inputs (the fuel flow rate and damper position) and two outputs (the temperatures in the front and the end of the kiln) into a first order, strong coupling linear system model and the validity of the model is verified as well. On the basis of the identified model, we design a decoupling controller. The simulation results show that the controller can accurately track the instructions to the temperatures at the front and the end of the kiln respectively with high stability and control accuracy. The method and conclusions of this paper may provide reference to the design of lime kiln combustion control system.