The Soft Measurement Technology And Its Applications In The Production Of Calcium Carbide

In the industrial process of calcium carbide manufacture,the resistance of charging stock control is the key to stabilize the quality of calcium carbide.The resistance of charging stock is determined by the resistivity of the calcium carbide.In order to control the value of the resistance of charging stock,the resistivity must be measured or estimated online.However, up to the present,the online measurement instrument of smelted furnace,which is precision, dependable,low cost and commercial,has not been developed throughout at home and abroad. Therefore,it is significant in theory and application to develop the soft sensing technology of the resistivity value in the industrial process of calcium carbide manufacture.In the first place,based on analysis the submerged arc furnace control system,the circuit diagram of calcium carbide furnace is presented and the value of resistance of charging stock under the optimization power is proved by geometry method.In the second place,the data preparation should be made up of online preparation and offline preparation has been presented.In the same time,the application flow chart has been given.Then,the least squares especially the recursive least square based on lethe gene is studied and the model of resistivity is built.In the follow place,based on analysis the precision descended of the model in the practice industrial process,a new method for online correction is presented which integrated the correction factors and the correlation coefficients.At the last place,based on the reasons of the model invalidation and the value of correlation coefficients between secondary variable and the primary variable,two offline correction rules is presented.In conclusion,this dissertation applied its main content to research and application of soft sensing technology of the resistivity value in the industrial process of calcium carbide manufacture.In some respects,such as data preprocessing,the least squares,the soft sensing model build,model correction and so on,has been lucubrated and some creative and helpful results are achieved after research work.The soft sensing technology,especially for the calcium carbide manufacture,should be enhanced,enriched and deepened by these results.In the same,these results should have reterence to soft sensor in other industrial process.