Research On Papermaking Process Quality Monitoring And Energy Consumption Optimization Control System

In general,the production process of the paper sheet is a dewater process.The production process of corrugated paper is to pass a 0.2% to 0.25% pulp through a series of dewater processes to form a dry paper web with a quantitative of 92% to 95%.During the entire dewater process,the energy consumption of the three main parts of the wire,press,and dryer section accounts for more than 70% of the energy consumed in the process of paper sheet making,thus reducing the energy consumption of the wire,press,and dryer sections for papermaking industry has an important significance.In this paper,a thorough investigation of the actual operation of a paper mill in Shanxi Province,and established monitoring systems for the three major parts of the paper machine wire section,press section and drying section,and according to different sections,it proposes a control scheme and method for reducing energy consumption.The main research contents of the paper are as follows:(1)A comprehensive analysis of the papermaking process was carried out.An on-line monitoring system was designed for the three main energy-consuming parts of the wire section,press section and drying section to monitor the three parameters affecting the dewatering effect and energy consumption of the paper sheet.(2)According to the vacuum level information collected by the monitoring system in the wire and press sections,energy saving control strategies are provided for the vacuum system of the wire and press sections,which measure the paper sheet dewatering volume and vacuum degree,and the dewatering volume and vacuum degree of the press fabric.The corresponding relationship between the network and the press section when the amount of dehydration is certain,to maintain the vacuum system working in the lowest vacuum state,so as to achieve the minimum energy consumption of the vacuum system in the case of meeting the dehydration requirements.(3)Establish a dry-temperature model between the sheet drying process and dryer temperature,for specific products,comparing the detected dryer temperature with the actual drying model,the actual temperature is compared with the ideal temperature to eliminate the error control.In the model comparison,the genetic algorithm is used to optimize the model to keep the dryer temperature at the maximum.Excellent status for the purpose of saving steam consumption.(4)For the energy-saving problem of the drive motor,by comparing the operating efficiency of the permanent magnet synchronous motor with respect to the three-phase asynchronous motor in different working conditions,the economic and technical conditions for using the permanent magnet synchronous motor instead of the three-phase asynchronous motor in the paper machine drive are obtained.The analysis shows that under normal machine power configuration conditions,as long as it is not always at full load,it is a feasible energy-saving measure.