Research On Pressure-controlled Optimization Of Steam System In Iron And Steel Enterprises

Iron and steel metallurgy industry has the characteristics of large-scale,long processes,and high energy consumption.At the present stage the conservation of resources and environmental protection has become China's basic national policy.In the sizeable integrated iron and steel works,the steam system has features of high inertia,long time delay,nonlinear,variation parameter and multivariable coupling,in such a complex operational and running state,dispatcher use extensive scheduling,system operation relying on years of production run experience,so as hard to avoid the occurrence of venting,degradation and so on,resulting in wasting.Therefore,it is necessary to optimize the steam pipe network of steel enterprises,improving the operation efficiency of the pipe network,ensuring the safety of the operation of the network.At first,the paper gives investigation and analysis of the steam pipe network system in iron and steel enterprise,computing model of steam pipe networks was established with hydraulic and thermal characteristic coupled.Fundamental of engineering thermodynamics,heat transfer and hydromechanics theory were used in the research work.Parameter identification of the equation can improve the operation efficiency and operation security of the pipe network.Considering the convergence rate of equations and meeting the need of practical engineering,the calculation accuracy is controlled within 3%.Coupled calculation equations can be used to calculating of static state pipe network,and provide effective help to grasp the current operating state.At the same time,coupled calculation equations can be used to optimize setting value of the pipe network pressure.Secondly,the main gas source and user's steam mode of production and using are analyzed.Finding out the primary gas source and user of influencing pipe network fluctuation.Initially establishing the quantitative relationship with the pipe network pressure;once more,establishing pipe network system forecasting model,based on Bayesian neural network.The forecasting model accuracy meets the demand of the field production through data validation,which indicates the validity of the prediction model.Finally based on the theory of decision tree,combined with enterprise scheduling discipline base,the field expert knowledge base and fact base,constructing dispatching rules decision tree system of iron and steel enterprises steam pipe network,making more reasonable and effective by the network scheduling strategy,greatly increasing the green area running time of network.Application of the steam pipe network optimization system in an iron and steel enterprise,before the system operation interval distribution of pipe network running is:green area accounts for 72.62%,yellow area accounts for 27.05%,red zone 0.33%;after the optimization system was put into operation,the red zone go away,yellow area run time dropped to 10.8%,green Zone running time up to 89.2%.Test results show that the steam pipe network optimization system can effectively increase the green area network operating time,reduce the yellow zone operation time of the pipe network,eliminating red zone running time basically,providing the strong guarantee for the steam pipe network running safely and effectively.The practical operation result shows that steam pipe network optimization system of the iron and steel enterprises.can effectively reduce the network fluctuation amplitude and frequency,improving the operation efficiency of the steam pipe network,guaranteeing the safe operation of the pipe network.Global rational optimization scheduling was necessary to the needs of steam for enterprise production,achieving the high efficient operation of the pipe network finally,savings cost for the enterprise.