基于PLC的污水处理系统设计

哈尔滨工业大学（威海）本科毕业设计（论文）-I-摘要本论文主要研究污水处理系统的PLC控制系统，随着城市的快速发展，环境问题显得日益重要。污水是破坏环境的一个重要因素，目前中国污水处理自控系统相对落后，污水处理成本居高不下，污水站排放的处理过的污水的水质不稳定，所以如何建立有效的自控系统，优化运行效果，具有重要的意义。文章首先介绍了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、状态信号等。最后按照工艺要求设计PLC控制系统，包括PLC的选型、系统资源配置以及按照污水处工艺编制PLC程序等。建立高度自动化污水处理站，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。污水处理站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；PLC；硬件配置；软件设计哈尔滨工业大学（威海）本科毕业设计（论文）-II-AbstractMymainresearchisthePLCcontrolsystemofsewagetreatment.Withtherapiddevelopmentofcities,theenvironmentbecomesmoreandmoreimportant.Wastewaterisoneofthemajorfactorofpollutetheenvironment.TheautomaticcontrollingsystemofwastewatertreatmentisnotveryadvancedinChina.Thewaterqualitiesofthetreatedwastewaterareunstable.Sohowtosolvetheproblemsisverymeaningfultoourcountry.Thispaperintroducedthehardwarestructure,workprincipleofPLCcontrolthesystemanddesignPLCcontrolsystem’sbasicprincipleandstep,thenwiththeSBRwastewatertreatmentcraftforexampletoillustratethePLCintheapplicationinthewastewatertreatmentprocess.Designedtheelectricitycontrolofequipmentsandautomaticallycontrolcircuitaccordingtothesewagetreatmentrequirements,mainlyincludethestartandstopofequipments,thestateofthesignalandsoon.FinallydesignPLCcontrolsystemaccordingtothetechnologicalrequirements,includethePLCtypeselection,theallocationofsystemresourcesanddrawupPLCprocedureaccordingtothewastewatertreatmentcraft.Establishahighlyautomatedofsewagetreatmentplant,notonlymaystrengthenthesystem’sreliabilitybutalsomayreducethelaborintensityandreduceprocessingcostsandsaveenergy.Theestablishmentofsewagetreatmentplant’sautomaticcontrolsystemwillreducetheproductionandmaintenancecosts,alsocanreduceproductionandmaintenanceworkersinthelaborintensity.Keywords:sewagetreatment;PLC;Hardwaredisposition;Softwaredesign哈尔滨工业大学（威海）本科毕业设计（论文）-III-目录摘要.....................................................................................................................IAbstract..................................................................................................................II第1章绪论..........................................................................................................51.1课题背景.....................................................................................................51.2课题目的和意义.........................................................................................51.3国内外发展现状.........................................................................................61.4本文研究的主要内容.................................................................................7第2章污水处理系统工艺流程..........................................................................82.1SBR的结构及工作原理..............................................................................82.2PLC控制系统设计原则与步骤..................................................................92.3污水处理工艺过程阐述...........................................................................102.4PLC与MCGS组态软件的通信...............................................................112.5本章小结...................................................................................................13第3章电气控制系统方案的选择及硬件设计................................................143.1PLC的工作原理........................................................................................143.1.1循环扫描技术....................................................................................143.1.2PLC的输入/输出响应时间...............................................................153.2SBR污水处理电气控制系统设计要求....................................................153.3SBR污水处理电气控制系统的总体设计................................................163.3.1设计过程............................................................................................163.3.2控制系统方案设计............................................................................173.3.3SBR污水处理电气控制系统硬件电路设计.....................................173.4本章小结...................................................................................................25第4章污水处理系统的软件设计....................................................................264.1污水处理系统软件设计的总体概述.......................................................264.2污水处理各个子程序的设计...................................................................264.2.1粗、细格栅除污机控制子程序的设计............................................264.2.2进水阀门控制子程序的设计............................................................284.2.3空气阀门、潜水搅拌机、回流污泥泵控制子程序的设计............294.2.4滗水器控制子程序的设计................................................................30哈尔滨工业大学（威海）本科毕业设计（论文）-IV-4.3本章小结...................................................................................................31第5章MCGS组态软件在本系统中的应用....................................................325.1对上位机监控软件的要求.......................................................................325.2上位机设计...............................................................................................325.2.1定义数据对象................