摘要：本课题根据毕业设计要求和苯酐装置精馏工段控制需求的具体情况，并结合PLC控制、组态软件、变频调速等技术，设计了一个基于PLC和力控组态软件的苯酐装置精馏工段的计算机自动检测与控制系统。其中涉及的内容主要有系统总体方案设计、PLC外围电路设计及其I/O口分配、PLC梯形图程序编写、计算机监控界面设计、通信组态配置等内容。通过选用西门子S7-200系列PLC，实现了对苯酐装置精馏工段控制系统中各个阀和供气、供邻二甲苯的实时在线检测与控制，大大提高了系统的可靠性和运行效率。在力控组态软件平台上开发的可视化监控软件，使对苯酐装置精馏工段控制系统的在线监测更加地直观、明了，提高了系统的人机交互水平和技术文档管理水平，也为苯酐装置精馏工段控制系统的自动化改造提供了参考依据。58111

毕业论文关键词： 力控；PLC；精馏

Phthalic anhydride device distillation section control system design

Abstract：This topic according to the graduation design requirements and benzene anhydride device distillation section control requirements of the specific circumstances, and combining with PLC and configuration software, frequency control of motor speed technology, designed a based on PLC and force control configuration software of benzene anhydride device distillation section of computer automatic detection and control system.Which involves the main content of system overall scheme design, the peripheral circuit design of PLC and its I/O port distribution and PLC ladder diagram programming, computer monitoring and control interface design, communication configuration configuration, etc.By choosing a Siemens S7-200 series PLC, realize the rectifying section of benzene anhydride device control system of each valve and gas supply, for real-time online detection and control of o-xylene, greatly improves the system reliability and efficiency.On force control configuration software platform development of visualization monitoring software, make of benzene anhydride unit control system of rectifying section is more intuitive, clear on-line monitoring, improve the level of the human-computer interaction system and technical document management level, also for phthalic anhydride plant automation transformation of the control system of rectifying section provides a reference basis.

Key Words：The force control；PLC；distillation

1 绪 论 1

 1.1　课题研究背景及苯酐生产工艺 1

  1.1.1 课题研究背景 1

  1.1.2 苯酐的生产工艺 2

  1.1.3 精馏介绍 3

 1.2　苯酐生产工艺的研究现状 4

  1.2.1 国内研究现状 4

  1.2.2 国外研究现状 5

 1.3 主要研究内容及实施方案 6

  1.3.1 主要研究内容 6

  1.3.2 实施方案 6

 1.4  软件方案选择 7

  1.4.1 PLC编程软件 7

  1.4.2 组态软件选择 8

  1.4.3 监控系统方案 9

２ 传感器的选型与控制电路的设计 10

 2.1 传感器原理及选型 10

  2.1.1 温度变送器的选择 10