摘 要
水资源和水环境是生物赖以生存的基础。随着我国城市化和工业化的快速发展，大量生活和工业废水的排放导致我国现有水源水质急剧下降，水污染日趋严重。为了保证中国经济的可持续发展，污水处理已成为城市发展不可或缺的支撑手段。
本课设介绍了PLC控制在澄清过程中的应用。在平台上，采用PLC作为控制器，结合各种在线仪器完成废水水质的检测。根据澄清过程的特点和系统控制的要求，完成现场设备的控制。监控系统使人员能够以远程控制方式对污水处理厂进行监控，系统还设计了工作报告功能。在该系统中，设计了格栅池、控制池、反应池和脱盐池装置，通过对脱盐池的最终浓度检测，可以保证污水中的盐分浓度的达到排放标准。
但是该系统存在一些缺陷，整个系统的设计简单，没有对污水中微生物排放的详细检测。在将来的设计中需要对此进行改进。 关键词：污水处理； PLC； 工艺技术；
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Abstract
Water Resources and water environment are the basis of biology existence.A large number of domestic and industrial waste water discharge has led to the rapid decline of water quality, water pollution is increasingly serious. In order to ensure the sustainable development of China's economy, sewage treatment has become an indispensable means of urban development.
This course introduces the application of PLC control in the clarification process. On the platform, PLC is used as the controller, and various on-line instruments are combined to complete the detection of waste water quality. According to the characteristics of the clarification process and the requirements of the system control, complete the control of the field equipment. The monitoring system enables people to monitor the Sewage Treatment by remote control, and the system is designed to report on work. In this system, a grid cell, a control cell, a reaction cell and a desalting cell are designed. By testing the final concentration of the desalting cell, the salt concentration in the waste water can be guaranteed to meet the discharge standard.
But there are some defects in the system. The design of the whole system is simple, and there is no detailed examination of the microorganism discharge in the sewage. This will need to be improved in future designs.
Key words: sewage treatment ;PLC; process;
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目 录
摘 要 ...................................................................... I Abstract .................................................................. II 第一章 绪论 ................................................................ 1
1.1 污水处理的国内外研究现状 ........................................... 1 1.2 课题的背景 .......................................................... 2 1.3 研究目的和意义 ...................................................... 2 1.4 课题主要设计的内容 .................................................. 3 1.5 本章小结 ............................................................ 3 第二章 污水处理系统的工艺介绍 .............................................. 4
2.1 常用的污水处理工艺 .................................................. 4 2.2 本设计污水处理工艺 .................................................. 5 2.3 本章小结 ............................................................ 6 第三章 污水处理系统的控制方案 .............................................. 7
3.1 污水处理系统的控制形式 .............................................. 7 3.2 控制方案的确定 ...................................................... 7 3.3 本设计的总体设计方案 ............................................... 8 3.4 本章小结 ............................................................ 8 第四章 硬件的设计 .......................................................... 9
4.1 污水处理的组成部分 .................................................. 9
4.1.1 格栅池 ........................................................ 9 4.1.2 调节池 ........................................................ 9 4.1.3 SBR反应池 .................................................... 9 4.1.4 除盐池 ....................................................... 10 4.2 设备的控制要求 ..................................................... 10 4.3 各类硬件的选型 ..................................................... 11
4.3.1 PLC选型 ..................................................... 11 4.3.2 电动机的选型 ................................................. 11 4.3.3 泵的选型 ..................................................... 12 4.3.4 曝气空压机的选型 ............................................ 13 4.3.5 浮球式液位计的选型 .......................................... 14 4.3.6 余氯仪的选型 ................................................. 15 4.3.7 模拟量模块的选择 ............................................ 15 4.3.8 阀门的选择 ................................................... 16 4.3.9 按钮的选型 ................................................... 17 4.3.10 接触器的选型 ................................................ 17 4.3.11 空气开关的选型 ............................................. 18 4.4 I/O分配表 ......................................................... 19 4.5 污水处理系统的主电路图 ............................................. 20 4.6 污水处理系统的外部接线图 ........................................... 20 4.7 本章小结 ........................................................... 22 第五章 软件的设计 ......................................................... 23
5.1 系统软件设计概念 ................................................... 23 5.2 系统软件的设计原则 ................................................. 23
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5.3 系统软件的介绍 ..................................................... 24 5.4 本系统的总流程图 ................................................... 25 5.5 程序的分段解释 ..................................................... 26 5.6 本章小结 ........................................................... 30 第六章 触摸屏 ............................................................. 31
6.1 触摸屏的简介 ....................................................... 31 6.2 触摸屏的主要特性 ................................................... 31 6.3 台达触摸屏人机界面的特点 ........................................... 32 6.4 触摸屏设计的界面解释 ............................................... 32 6.5 本章小结 ........................................................... 36 第七章 三菱PLC的仿真 ..................................................... 37
7.1 程序 ............................................................... 37 7.2 本章小结 ........................................................... 39 第八章 小结 ............................................................... 40 参考文献 .................................................................. 42 附录A 主电路图 ............................................................ 43 附录B PLC外部接线图 ...................................................... 44 附录C 主程序 .............................................................. 45 附录D 元器件清单 .......................................................... 51
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PLC的污水处理系统的设计案例
