水泥回转窑温度控制研究

发布时间：2018-06-02 00:32

本文选题：回转窑温度 + 优化设定　；参考：《济南大学》2017年硕士论文

【摘要】：回转窑煅烧过程是水泥熟料生产的关键环节,其通过调节窑头喷煤量来稳定回转窑温度,从而得到质量合格的水泥熟料。其中,窑头用煤量约占整个水泥熟料生产煤耗量的40%。但是由于回转窑大滞后、非线性、多变量耦合等复杂特性,使得国内水泥回转窑控制大多还采用人工控制方式,人工控制水平参差不齐,很难保证较好的控制效果,且能耗较高。国外的一些优化控制软件虽然有较好的控制效果,但是难以适用国内水泥厂原材料波动大、测点少等现状。因此,基于国内回转窑控制现状,研究采用先进控制策略实现回转窑煅烧过程的优化控制,稳定回转窑煅烧温度,进而降低生产能耗,提高水泥质量是一个亟待解决的重要课题。本课题以山东省某水泥厂5000t/d水泥熟料生产线为研究背景,在了解生产工艺的基础上,结合操作专家经验,采用多模态智能控制方法,提出由回转窑温度优化设定系统和自动控制系统组成的水泥回转窑温度优化控制系统总体解决方案;然后,采用面向对象编程策略,研发了水泥回转窑温度优化控制系统软件并进行了现场应用。具体研究内容如下:(1)回转窑温度优化设定系统研究。基于水泥烧成系统工艺,结合操作专家经验,采用LS-SVM建立回转窑温度预设定模型;然后分析总结不同窑况,结合出窑熟料中f-CaO含量,构建温度预设定值修正专家规则,修正回转窑温度预设定值,得出当前窑况下的回转窑温度最优设定值,作为回转窑温度自动控制系统的控制目标值。(2)回转窑温度自动控制系统研究。针对回转窑大滞后、非线性、多变量耦合的特性,提出将Bang-Bang控制、专家规则控制、前馈控制与模糊-PID复合控制相结合的多模态智能控制方案。在工况稳定情况下,采用模糊-PID复合控制实现回转窑温度稳定控制,当工况发生变化时,根据多模态智能切换规则,切换相应模态下的控制器对模糊-PID复合控制进行校正,将回转窑温度稳定在最优设定值;然后选取回转窑典型工况,进行了仿真验证。(3)回转窑温度优化控制系统软件研发。根据回转窑温度优化控制系统总体方案,采用面向对象编程策略,将整体系统分为数据采集子系统,数据库子系统,优化控制子系统,并分别进行研发。通过ADO实现优化控制子系统与数据库子系统的数据互联;通过OPC数据采集子系统实现数据库子系统与现场DCS系统数据互联。最后,将回转窑温度优化控制系统应用于生产现场。结果表明,回转窑温度更加稳定,煤耗更低。因此本课题的研究对水泥熟料的高质低耗生产的意义重大。
[Abstract]:The calcination process of rotary kiln is the key link of cement clinker production. It can stabilize the temperature of rotary kiln by adjusting the quantity of coal injection at the kiln head and get the cement clinker of qualified quality. The coal consumption of kiln head accounts for 40 percent of the total coal consumption of cement clinker production. However, due to the complex characteristics of rotary kiln, such as large lag, nonlinear and multi-variable coupling, the cement rotary kiln control in China is mostly controlled by manual control, and the level of manual control is uneven, so it is difficult to ensure better control effect. And the energy consumption is high. Although some foreign optimization control software has good control effect, it is difficult to adapt to the domestic cement factory raw material fluctuation, less measuring points and so on. Therefore, based on the current situation of rotary kiln control in China, the advanced control strategy is adopted to realize the optimal control of the rotary kiln calcination process, to stabilize the rotary kiln calcination temperature, and then to reduce the production energy consumption. Improving cement quality is an important task to be solved. Based on the research background of 5000t/d cement clinker production line in a cement factory in Shandong Province, this paper adopts multi-modal intelligent control method based on the understanding of production technology and experience of operation experts. The overall solution of cement rotary kiln temperature optimal control system composed of rotary kiln temperature optimal setting system and automatic control system is put forward, and then the object-oriented programming strategy is adopted. The optimum temperature control system software of cement rotary kiln is developed and applied in the field. The specific research contents are as follows: 1) the system of optimizing the temperature of rotary kiln. Based on the process of cement sintering system and the experience of operation experts, the temperature pre-setting model of rotary kiln is established by using LS-SVM, and then different kiln conditions are analyzed and summarized, and the expert rules for modifying temperature pre-setting value are constructed by combining f-CaO content in kiln clinker. The temperature preset value of rotary kiln is revised and the optimal setting value of rotary kiln temperature under current kiln condition is obtained, which is used as the control target value of automatic temperature control system of rotary kiln. 2) the research on automatic temperature control system of rotary kiln. Aiming at the characteristics of large lag, nonlinear and multivariable coupling of rotary kiln, a multi-modal intelligent control scheme combining Bang-Bang control, expert rule control, feedforward control and fuzzy-PID compound control is proposed. Under the condition of stable working condition, the fuzzy pid compound control is used to realize the temperature stability control of rotary kiln. When the working condition changes, the fuzzy pid compound control is corrected by switching the controller under the corresponding mode according to the multi-mode intelligent switching rule. The temperature of rotary kiln is stabilized at the optimal setting value, and then the software of temperature optimization control system of rotary kiln is developed by selecting typical operating conditions of rotary kiln. According to the overall scheme of rotary kiln temperature optimal control system, the whole system is divided into data acquisition subsystem, database subsystem and optimal control subsystem by using object-oriented programming strategy. The data interconnection between the optimization control subsystem and the database subsystem is realized by ADO, and the data interconnection between the database subsystem and the field DCS system is realized by the OPC data acquisition subsystem. Finally, the rotary kiln temperature optimization control system is applied to the production site. The results show that the temperature of rotary kiln is more stable and the coal consumption is lower. Therefore, the research of this topic is of great significance to the production of cement clinker with high quality and low consumption.
【学位授予单位】：济南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ172.622;TP273

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