Research Of Optimal Scheduling Model Of Intermittent Production Equipment In Tissue Paper Pulping Process

Excessive production capacity of tissue leads to fierce market competition.How to reduce production costs to improve competitiveness is a problem that enterprises need to solve urgently.The electricity cost of the paper industry accounts for 51% of the total energy cost.Compared with other paper production processes,tissue has a higher proportion of electricity cost in the pulping process.At present,the domestic tissue pulping process scheduling is carried out only by the workers visually observing the production situation,which has the problem of unscheduled scheduling and cannot reduce the cost of the pulping process to the best.Therefore,this paper uses the on-site production data of the pulp and papermaking process to establish a mathematical model which is for the pulping process of tissue.In this study,different optimized scheduling models were established and the results were analyzed to achieve automated production management for the enterprise.First,a quantitative model is established for the pulping process of tissue,which is mainly a mathematical model of slurry flow rate,a quantitative model of slurry liquid level and slurry volume in the slurry tank.Secondly,this paper collects the relevant data of the pulping and papermaking production line from a tissue enterprise,and perform data preprocessing on the collected data(including removing outliers and filling of missing values).Finally,the processed data is input into the above quantitative model as a data source to obtain input data for subsequent models.This paper proposed a scheduling plan model for intermittent production equipment for tissue pulping process based on NSGA-II algorithm.The above data is used as the initial input data of the scheduling plan model.According to the characteristics of the pulping line and the configuration of the slurry tank,the electricity cost and processing time of the intermittent production equipment are the objective functions,and the slurry level in the slurry tank is the constraint.The model finally outputs the optimal scheduling plan.Therefore,the model can scientifically arrange the processing time of the equipment,which could cut peaks and fill valleys,and reduce the cost of electricity.In order to solve the problem of unstable and complicated working conditions in the pulping process,a dynamic optimization scheduling model for intermittent production equipment in the pulping process of tissue based on the mathematical planning method was established.The initial input data of the equipment dynamic optimization scheduling model is the above data and the planned production volume.The cost of electricity for intermittent production equipment is the objective function of the model.Finally,the model outputs the optimal equipment scheduling results based on the characteristics of the pulping line,the configuration of the equipment,the liquid level of the slurry in the slurry tank,and the peak and valley electricity prices.According to the scheduling result,the control system controls the start and stop of the equipment,which could make full use of the processing time during the trough period,and reduce the power cost of the pulping process.As the name implies,model is rescheduled and updated the scheduling decision when the conditions of the pulp line or papermaking line change.In order to realize the industrial application of the intermittent production equipment optimization scheduling model for the tissue pulping process.According to the requirements of a tissue company,this paper uses the pulping and papermaking data to deploy the pulping equipment scheduling plan model to pulping line in a factory.The results show that scheduling plan model of intermittent production equipment in the tissue pulping process can save the electricity cost by 551 yuan per day,approximately 15.2% of actual dispatched electricity cost.In addition,this paper collects the pulping and papermaking related data from a tissue company as the input data.The results show that the pulping equipment scheduling plan model can save 454 yuan in electricity costs for the plant every day,approximately 13.8% of actual dispatched electricity cost.Therefore,whether it is a scheduling plan model or a dynamic optimization scheduling model,the results show that it can reduce the electricity cost of the pulping process.And the model can be successfully applied to the papermaking enterprise.