Study On Hydrocracking Production Optimization Based On Data Reconciliation

The hydrocracking process occupies a dominant position in the conversion process of heavy oil to light oil in petrochemical industry enterprises.In the production state of hydrocracking,such as temperature,pressure,concentration,and flow rate,it all needs to be monitored and controlled during the entire operating cycle of the industrial process.The process production status information is continuously provided to the staff and stored for possible subsequent data mining provide historical data.However,the values of these variables that we have measured are more or less affected by random errors and serious errors.Such low reliability can be caused by improperly calibrated measuring equipment,broken pipelines,leaks,artificial elements,unstable energy supply,or other elements in the transversion.There is another difficulty in the monitoring process,that is,due to high cost or technical obstacles,some process state variables cannot be effectively measured.Therefore,it is necessary to reconciliation the variables that can be measured,and perform robust estimation of unmeasured variables based on these values,so as to provide highly reliable data for process control and optimization solutions.This process is the data reconciliation(DR)process.In this process,the measurement data is coordinated(fitted)by the estimator,it is a maximum likelihood objective function based on the postulation of statistical distribution measurement error to meet certain conservation laws and process constraints,thereby obtaining process state variables and reliable estimates of parameters.Firstly,this article discusses the technologies involved in data coordination,including the basic concepts of data coordination and related calculation methods,the identification and elimination of gross errors,and the objective function of the data coordination problem.A new data coordination objective function is proposed,and its effectiveness and robustness are verified by comparison.Secondly,the process flow of hydrocracking in petrochemical industry is introduced,and its fractionation stage and secondary hydrogenation reaction stage are simulated by Aspen Plus.Subsequently,the established simulation process is applied to data coordination as a constraint condition.Using the powerful physical property database in Aspen Plus,compared with the constraint model established by mathematical methods,it can be more suitable for actual production,and when the production status changes,process simulation based on physical data will have better adaptability.Finally,using the data after data coordination,the production optimization of the debutanizer in the hydrocracking process was analyzed.That is to analyze and adjust the controllable operating conditions,reflux ratio and distillate feed ratio of the debutanizer in the production state,so that the debutanizer can obtain more economical and efficient operating parameters under the current conditions.After analysis and adjustment,the distillation purity of the de C5 column can be as high as 99% or even higher.