Research On Predictive Control In Grate Cooling Process Of Cement Clinker

Cooling process is important to the sintering process of cement. It plays an important role in cooling,conveying and reclaim the heat of clinker. Grate cooling process is the most popular cooling methods in modern cement plant, and its automation is one of the most difficult problems in cement production.Under the reasonable assumption and the actual characteristics of grate cooling in stable working condition, the thermodynamics model of the grate cooling process is built at first. And then the simulation was given on the model combined with the real data. Associated with the grate cooling process reality of Daba Cement Plant and the character of DCS, designed the grate cooling control system which using predictive control algorithm based on grey model. The control system programmed by VC++ and based on OPC technology. The practice shows that the algorithm is correct and practical.According to the technology characteristic of grate cooling, the operation character and the main factors of cooling process were analyzed deeply to the third type generation of aeration beam grate cooler. The main factors include the clinker thicken and granularity etc, studying the relationship between the influence of these factors and grate cooling process. But the influence of these factors can hardly measure directly until now while reflect by the character of changes of the second chamber under grate cooler. Parameters of the classic predictive controller model have usually been not ascertained easily as the process parameters fluctuate greatly. And then, the improved Back Propagation neural net and based on fixed data were used to make model for grate cooling process. But it is no useful to controller. The grey model has the advantages of self-adaptive, so it is fit for the control of grate cooling process. So, the paper proposed the predictive control of grate cooling based on grey model. And its controlled variable is the pressure of the second chamber of grate cooler, control variable is the first drive velocity.Associated with the reality of Daba Cement Plant, the predictive control algorithm using VC++ language realized data communication with DCS control system by the OPC interface. Further more the software of this project emphasized and actualized the modularization, it is reduced the cost while enhanced the universality and transplantation. According to the predictive control based on grey model proposed, the practical operation result shows that the algorithm has good effect on grate cooling process control.