Research On Temperature Control Of The ATP Furnace

With the price of oil getting higher and higher, oil shale industry is received more and more concern. In the oil shale industry ATP is an advanced process. The output of shale oil is depended on the quality of control in ATP furnace especially the quality of temperature control. Therefore, it is necessary to research on temperature control of ATP furnace.The thesis takes shale oil refining production line in shale oil refining factory as the background, and expounds the structure composition and working principle of ATP furnace. In the paper it is analyzed for ATP furnace temperature control system in detail and then it is put forward the difficulty in controlling temperature of ATP furnace. Namely while thermal load is changed since the feed rate is changed for some reason and then how to control the combustion air flow rate in order to keep the temperature of retort zone in ATP furnace as the best process temperature. It can be concluded that the temperature object itself has inertia and delay features. However, as the factors that influence the temperature during the oil shale retorting are complex, it is difficult to describe the temperature object using precise mathematical model. To avoid the effects of characteristics of the temperature object on the control system, the internal model control approach is used to design ATP furnace temperature control system, combined with the characteristics of internal model control for instance simple structure, clear reorientation and strong anti-interference ability. In order to overcome the matching error between object and internal model, filter is added in the feedback loop.Finally, the author uses the ControlLogix PLC which is the same kind control system as ATP furnace to build an experimental model for a simulation study. Moreover, the temperature control system improved by this paper is compared with traditional PID control system by using trend function of ControlLogix programming and debugging software and also the effects of filter parameter on system performance and disturbance response curve of the system are analyzed. The emulation results show that internal model control structure has good performance for the temperature control system of ATP furnace with large inertia and pure lag.