Research On Soft Prediction And Fuzzy Control Of Location Of Smoke Spray Gun With Oxygen - Enriched Top

In the non-ferrous metallurgical industry, the oxygen enriched air and top-blown technology is widely used in melting, curing and redox processes.The oxygen enriched air and top-blown furnace is mainly used in oxygen top blown submerged lance technology, which is a kind of advanced production technology in nonferrous metallurgy industry. Oxygen top blown smelting is accomplished through a lance operation,which is the core technology of the oxygen enriched air and top-blown furnace. In order to meet the melting technology requirements, the lance in molten pool must be ensured in a suitable inserted depth to maintain good stirring and mixing intensity during the continuous melting process. If the lance inserted depth is not enough, the foaming slag will be produced easily. However, if the lance inserts too deep,the material that at the bottom of the furnace will be stirred up to accelerate the lance loss, while impact the smelting reaction efficiency, furnace body and its lifetime. So the lifetime of the lance and the quality of the product is directly related to the position of the lance control.Soft measurement combine the theory and production process, which related to the application of computer technology, choose some variables associated with the dominant and easily on-line measurement of the variables, using modeling methods to get soft measurement model to achieve the dominant variables. The main modeling methods are multiple linear regression, principal component analysis method, least square method and the establishment of mechanism model method etc.Currently, the lance location is descriped with lance position and inserted depth of representation. Among them, the position of the lance is obtained by the position incremental encoder which installed on the winch system,but data does not take into account the burning issues in the smelting process of lance. At the same time, due to the melt surface, the content of MgO and Fe3O4, the melt temperature and static pressure (end pressure) lance value and many other factors, the exact value of the lance is difficult to directly measure online. In order to ensure the normal melting, the lance inserted depth should be stabled at requires200mm-400mm. This paper established MLR and PCR soft prediction model of the lance position, and it is verified that the model has good forecast effect.This paper established a hydrostatic model lance inserted depth and static pressure (end pressure), on the basis of field operation experience. At the same time, on the basis of a comprehensive analysis of the working principle and environment of furnace, based on the knowledge of fluid mechanics the depth of insertion mechanism on the lance model is determined.The availability of the mechanism of the model is determined by comparative studying.On the basis of the lance inserted depth mechanism model, this paper establish lance static pressure (end pressure) dynamic mathematical model.By analyzing the oxygen enriched air and top-blown technology and working principle of the lance,this paper comparing PID control and fuzzy control,ensure the better control scheme,and laid the foundation of lance control. In this thesis, the OPC interface technology achieved the digital communication work between the Matlab and WinCC7software platform providing the conditions for the realization of the lance control in practical engineering.The feature of this thesis:firstly, establish a mechanism model for lance inserted depth; Secondly, using PID control and fuzzy control methods to control static pressure (end pressure),and the fuzzy control is determined has better effect; Thirdly, on the WinCC7.0software platform,the static pressure (end pressure) and lance inserted depth can be read. Through both control of the lance,the real-time on-line control can be achieved.