【作者】 罗振涛；

【导师】 段玉波；

【作者基本信息】 东北石油大学 ， 电气工程， 2011， 硕士

【摘要】 pH值在石油化工工业生产中是常见的过程控制对象,但由于其特殊的过程特征,在绝大多数的控制过程中只能处于开环控制或接点控制状态,无法实现连续、精细调节控制目标。这种控制状况,显然不能满足那些对于pH值要求较高的石化生产过程的需要。而由于pH值的波动,可能造成生产过程波动,产品质量不稳,产品产量降低,能耗物耗浪费严重,设备腐蚀和环境污染等情况。本文简要介绍了采用复杂控制技术,对裂解急冷水的PH值进行自动控制,通过一些先进的技术手段,可以同时将急冷水和相关联的工艺水的PH值,稳定在一定的控制区间内。在避免急冷水PH值过高引起急冷水乳化的同时,减少因急冷水PH值过低对工艺水汽提塔和众多换热器等设备酸性腐蚀的可能性。同时对稀释蒸汽发生器也起到较好的保护作用,为急冷水装置、工艺水汽提装置及稀释蒸汽装置设备的平稳运行提供有效保证,有利于乙烯装置安全的长期稳定运行,并使相关设备的运行寿命延长,从而降低维护保养费用。改造后的裂解装置急冷水系统PH值自动控制控制系统投产至今,整个控制过程运行连续稳定,控制系统具有较好的鲁棒性,快速性和稳定性,系统具有较强抗干扰能力和系统跟踪能力更多还原

【Abstract】 pH value of production in the petrochemical industry is a common process control objects, but because of its special characteristics of the process, the control process in the vast majority only in the open-loop control or contact control condition, can not achieve continuous fine-tuning control objectives . This control situation, obviously does not meet those requirements for higher pH values the needs of the petrochemical production process. And because the pH fluctuations can cause fluctuations in the production process, product quality unstable, reduce product yield, a serious waste of energy and material consumption, equipment corrosion and environmental pollution and so on.This paper describes the use of sophisticated control technology, the PH value of cold cracking emergency automatic control, through a number of advanced techniques, can be associated with acute cold water and process water, PH value, stability control in a certain range. PH value to avoid excessive cold water caused acute and acute cold water emulsion at the same time, reduce the PH value is too low acute cold vapor stripper and a number of process heat exchangers and other equipment, the possibility of acid corrosion. While the dilution steam generator also play a better protective effect for acute cold water installations, process equipment and dilution water vapor to mention the smooth operation of steam plant equipment to provide effective guarantees, will help secure the long-term stability of ethylene plant operations, and related equipment operational life extended, thereby reducing maintenance costs.After transformation, the cracker PH value of the chilled water system emergency control system of automatic control of production so far, the entire control process continuous and stable operation, the control system has good robustness, speed and stability, the system has strong anti-interference ability and tracking system ability更多还原