【作者】 邱军；

【导师】 陈良才； 罗自学；

【作者基本信息】 华中科技大学 ， 动力工程及其自动化， 2007， 硕士

【摘要】 21世纪,我国面临着能源供应的问题,尤其是液体燃料短缺的难题。作为一种新的能源,生物质气合成二甲醚是解决能源问题的一个重要途径。因此,本文对二甲醚合成工艺的参数测量与过程控制进行了研究,为二甲醚合成工艺的研究提供了帮助。二甲醚合成的工艺要求反应的温度在280℃,压力在3～5MPa。反应在两种不同的常见反应器中进行,一个是反应釜,另一个是管式反应器。同样的反应在不同的反应器中进行,可以得出不同的产率,从而确定哪种反应装置更适合用来合成二甲醚。我们的任务就是为二甲醚合成过程提供必要的温度、压力、流量等工艺条件。选用了以研华工业控制计算机和板卡为核心的开发平台。其中,工业控制计算机型号为IPC610BP,信号输入输出板卡为PCL-813B、PCL-727和PCL-730,控制算法在工业控制计算机中运行。现场传感器和变送器的信号首先进入到数字显示仪表中,再由数显仪表的变送端输出变送信号到端子板,进入到板卡的采集端子,从而进入计算机。控制系统有两路执行机构,每一路由一个电磁阀和一个电动调节阀组成,分别完成对系统压力和温度的自动调节。控制算法主要采用比例调节算法和常规PID算法。首先,将连续PID公式进行离散化处理,再编写相应的程序。最后,再进行控制参数的整定和系统联动调试。控制参数的整定综合应用了理论计算法、经验公式法和凑试法。系统调试后,可实现压力的自动控制。更多还原

【Abstract】 In 21centry, China faces challenges in energy supply, especially the liquid fuels. as a new kind of fuels, that the synthesis of dimethyl ether from biomss syngas is a very important way to overcome the challenges. Therefore, the process control of the synthesis of dimethyl ether is been studied in this paper, and then give the basics for industrial scale applications.The synthesis process of dimethyl ether demands that the temperature is 280℃and the pressure is from 3MPa to 5 MPa. The reaction is accomplished in two different reactors, one is reaction vessel, and the other one is fixed bed bubble reactor.According to that the same reaction was accomplished in two different reactors, we got two different yield rate, so we can determine which reactor is better for the synthesis of dimethyl ether.Our tasks were provided necessary technological conditions for the synthesis of dimethyl ether, such as temperature, pressure and flow etc.In order to be convenient for development, we chose the core developing platform based on Advantech industrial control computer and cards. The type of the industrial control computer is IPC610BP, and we chose three cards, they are PCL-813B、PCL-727and PCL-730.The three cards were used to collect signals, and control algorithm was run in the industrial control computer.First, the signals of field sensors and transmitters entered the digital display instruments, and then according to the Transducer terminals of the digital display instruments, the field signals were connected to terminal boards of the cards, so the signals entered the industrial computer through the cards.The actuator of the control system included two electromagnetic valves and two electric regulating valves. One electromagnetic valve and one electric regulating valve were in one group, the two groups accomplished the temperature regulating and the pressure regulating.We mainly used the proportion control algorithm and normal PID control algorithm. Frist, we discretized the continuous PID formula, and then wrote relevant computer program. At last, we accomplished the tuning of the system technological parameters and the system testing and commissioning.The main methods of parameter tuning include theoretical calculation method、empirical formula method and try and error method etc. After debugging and adjusting the system, automatical control of system pressure is realized.更多还原