发布时间 : 星期六 文章基于PLC的城市污水处理系统更新完毕开始阅读
本科生毕业设计（论文） 摘 要
随着城市的快速发展，环境问题也越来越严重。城市污水是破坏环境的一个主要的因素，目前我国城市污水处理系统相对落后，污水处理成本高，所以如何建立有效的自动控制系统，减少运行费用，具有重要意义。
本文论述了城市污水处理系统的基本工艺和流程，并设计了一套基于PLC控制的城市污水处理系统。
本系统包括硬件设计，软件设计和监控组态设计三个方面，实现了中小型城市的污水处理自动控制和远程监控。首先介绍了PLC控制系统的硬件结构、工作原理以及设计PLC控制系统的基本原则和步骤，然后以SBR污水处理工艺为例，来说明PLC在污水处理过程中的应用。先根据污水处理要求设计了设备的电气控制与自动控制线路，主要包括设备的启停、状态信号、故障信号和信号采集等。最后按照工艺要求设计PLC控制系统，其中包括PLC的选型、系统资源配置以及按照污水处理工艺编制PLC程序等。建立高度自动化污水处理厂，不仅可以加强整个系统的可靠性、准确性，还可以减少劳动强度，降低处理成本和节约能源。污水处理厂自动控制系统的建设将降低生产和维护成本，减轻生产及维护工人的劳动强度，并为生产工艺的进一步改进提供方便，具有很好的经济效益和社会效益。
关键词：污水处理；SBR；PLC；自动控制
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本科生毕业设计（论文） Abstract
With the rapid development of the city,environmental problems are becoming more and more serious.City sewage is a major factor in the destruction of the environment, the current sewage treatment system of our city is relatively backward,the high cost of sewage treatment,so how to establish the automatic control system effectively,reduce the operation cost,has important significance.
This thesis discusses the city sewage treatment technology and process,and design a set of city sewage treatment system based on PLC control.
The system includes hardware design,software design and monitoring configuration design three aspects,to achieve automatic control of wastewater treatment for small and medium cities and remote monitoring.Firstly,the basic principles and steps PLC control system hardware structure,working principle and design of PLC control system,then SBR wastewater treatment process as an example to illustrate the application of PLC in the sewage treatment process.According to the sewage treatment designed first electrical control equipment and automatic control circuit,including the start and stop equipment,status signals,fault signals and signal acquisition.Finally,in accordance with the requirements of the design process PLC control system,including the configuration selection,system resources,and the PLC in accordance with the sewage treatment process,such as the preparation of the PLC program.Build a sewage treatment plant is highly automated,not only can enhance overall system reliability,accuracy,but also can reduce the labor intensity,lower processing costs and energy savings.Construction of sewage treatment plant automatic control system will reduce production and maintenance costs,reduce labor intensity of production and maintenance workers,and to facilitate the further improvement of production processes,with good economic and social benefits.
Key words：Sewage treatment；SBR；PLC；Auto-Control
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本科生毕业设计（论文） 目 录
第1章 绪 论 .......................................................................................................... 1
1.1选题背景 .................................................................................................... 1 1.2国内外研究现状 ........................................................................................ 2 第2章 污水处理工艺 ............................................................................................ 4
2.1 污水处理概况 ........................................................................................... 4 2.2 常见的污水处理工艺 ............................................................................... 5 2.3 SBR工艺阐述 ............................................................................................ 7 2.4 系统设计的方案 ....................................................................................... 8 2.5 系统组成总体结构 ................................................................................... 9 第3章 硬件设计 .................................................................................................. 10
3.1 PLC的介绍 .............................................................................................. 10
3.1.1 PLC的结构 ................................................................................... 10 3.1.2 PLC的工作原理 ............................................................................11 3.1.3 PLC选择 ....................................................................................... 12 3.1.4 PLC I/O口分配 ............................................................................. 13 3.2 SBR法的总体设计 .................................................................................. 15 3.3 其他硬件设计 ......................................................................................... 17
3.3.1 电机的选择 .................................................................................. 17 3.3.2 鼓风机 .......................................................................................... 17 3.3.3 接触器选型 .................................................................................. 18 3.3.4 液位计选型 .................................................................................. 18 3.3.5 滗水器选型 .................................................................................. 19 3.3.6 PH仪 ............................................................................................. 20 3.3.7 溶氧仪 .......................................................................................... 20
第4章 软件设计 .................................................................................................. 21
4.1 编程软件STEP7-Micro/WIN概述 ........................................................ 21
4.1.1 STEP7-Micro/WIN简单介绍 ....................................................... 22 4.1.2 梯形图语言特点 .......................................................................... 22 4.1.3 STEP7-Micro/WIN参数设置 ....................................................... 23 4.2 PLC程序设计 .......................................................................................... 24
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本科生毕业设计（论文） 4.2.1 整体设计流程 .............................................................................. 24 4.2.2 手动设计流程 .............................................................................. 25 4.2.3 自动控制流程 .............................................................................. 25
第5章 人机界面 .................................................................................................. 29
5.1 组态软件的介绍 ..................................................................................... 29 5.2 设计要求及效果 ..................................................................................... 30 5.3 定义数据对象 ......................................................................................... 31 5.4 主界面设计 ............................................................................................. 31 5.5 实时报警 ................................................................................................. 33 5.6 脚本程序 ................................................................................................. 34 第6章 结 论 ........................................................................................................ 37 参考文献 ................................................................................................................ 38 致 谢 ...................................................................................................................... 40 附 录Ⅰ ................................................................................... 错误！未定义书签。 附 录Ⅱ ................................................................................... 错误！未定义书签。 附 录Ⅲ ................................................................................... 错误！未定义书签。
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