【作者】 王春亮；

【导师】 李茜；

【作者基本信息】 陕西科技大学 ， 控制理论与控制工程， 2012， 硕士

【摘要】 造纸工业作为促进社会发展的基础性工业，为人类文明成果得以保存和传承提供了载体。在西方经济发达国家，造纸工业已经成为促进其社会经济发展的支柱性产业。但是，国内造纸企业却面临着木材原料短缺，对环境污染严重，水、电等能源消耗巨大的困境。废纸作为一种可循环利用的纤维资源，在一定程度上可以替代木材纤维。2010年造纸工业原料中，废纸浆占到了62.7%，这一比例仍会继续提高。近几年来，已经能够使用100%废纸脱墨浆生产出质量上乘的面巾纸、新闻纸等。由于废纸纤维强度较低并且含有的杂质较多，为了提高浆料的质量以生产出合格的纸张，制浆过程的规模不断扩大，技术水平不断提高，人工操作很难达到控制要求。为了提高废纸制浆的效率，保证生产过程的连续高效运行，降低单位产量的能源消耗，需对废纸制浆过程的自动控制系统进行研究。以达到节约能源、清洁生产的目标。论文从以下三个方面展开了工作。（1）废纸制浆工艺过程介绍及控制方案的设计。在介绍废纸制浆工艺的基础上，分析了制浆过程中不同设备的控制要点。对碎浆过程中白水与废纸加入量，压力筛进浆、良浆流量及反冲洗水进行比值控制；对杂质分离机、浮选脱墨槽、热分散系统中的各类阀门、浆泵进行时序控制；对浮选脱墨过程中的油墨液位采用串级控制。（2）热分散过程温度控制器的设计。模糊控制不依赖于被控对象精确的数学模型，对大滞后、时变过程具有良好的控制效果。PID控制器具有结构简单、使用方便等特点，在许多控制场合中占据主导地位。针对热分散过程浆料加热存在滞后，难以建立精确数学模型的问题，设计了一种模糊PID控制器。通过Matlab7.0仿真分析，表明该算法具有抗干扰能力强、控制精度高的特点。（3）控制方案的实现。以西门子S7-400PLC为硬件平台，WinCC v6.0为组态软件，完成了制浆过程控制系统的设计，并将模糊PID控制算法上位机中进行编程实现。更多还原

【Abstract】 As a basic industry, paper industry promotes the social development, itpreserves and transmits the achievement of human civilization. In the westerndeveloped countries, paper industry has become one of the pillar industrieswhich promote the social and economic development. However, the domesticenterprises have been facing many problems, such as raw materials shortage,worse environment and water, electricity energy enormous consumption. As arecycled fiber resource, the waste paper can replace the wood fibers on someextent. In2010, waste paper pulp accounted for62.7%of paper industry rawmaterial, and the ratio is still increasing. In recent years, waste paper deinkingpulp (100%) has been able to produce high quality facial tissue, newsprint and soon.However, the waste paper fiber with low strength and contains lots ofimpurities. The qualified paper is produced by improving the quality of the slurry.The scale of pulping process constantly is expanded and the technology is alsoimproved, the manual operation cannot satisfy the control requirements. Forimproving the efficiency of the waste paper pulping, and ensuring the continuousand efficient operation process, the automatic control system of the waste paperpulping process is studied, so that the production is kept in a good state, forexample, the energy consumption of per unit yield is reduced, energy resourcesare saved and a cleaner production is realized. In this paper，the main work andachievements are included as follows.(1) The introduction of pulping process and its control scheme design. Onthe basis of introducing the waste paper pulping process, the control points ofdifferent production equipments in the pulping process are analyzed. In order toimprove the efficiency of pulping, the variables are controlled by ratio control,such as the addition amount of white water and waste paper; the flow of pulpfeed, accepted stock and the backwash water of pressure screen. A variety of instruments and equipment are controlled by sequence control, such as theimpurity separator, flotation deinking cell, heat disperser, and various types ofvalves. In the flotation deinking, the ink level is controlled by cascade control.(2) The design of temperature controller in hot dispersion process. Fuzzycontroller does not depend on the accurate mathematical model of controlledobject, which shows a good control performance and strong robustness in thelarge time delay, time-varying processes. PID controller has the characteristics ofsimple structure and easy implementation, which is used extensively in industrialproduction processes. In the hot dispersion process, the pulp heating processfaces with the problem of large time delay and it is difficult to establish itsaccurate mathematical model, so the fuzzy PID control algorithm has beenproposed. By using the matlab7.0platform, the simulation results show that thecontroller has the characteristics of strong robustness and high control accuracy.(3) The realization of control system. Siemens S7-400PLC is used as thehardware platform. The WinCC V6.0is used as the configuration software; thecontrol system of waste paper pulping process is achieved. Fuzzy controlalgorithm is programmed in the host computer.更多还原