Abstract: Aiming at the control bottleneck caused by the strong coupling, strong interference, and nonlinearity of a waste liquid incineration system, an improved linear active disturbance rejection control (LADRC) strategy based on an ideal model is proposed. First, the ideal model is established for the incineration process, and the corresponding LADRC is designed. Then, the controller is applied to the ideal model and actual system. A PID neural network compensator based on the output deviation of the two models is established, and the traditional LADRC is improved using this compensator to improve the ability of observation and anti-disturbance caused by the limitation of the observer by the system itself. The simulation results show that the improved LADRC has a stronger anti-disturbance ability and better robustness than the PID control and traditional LADRC.