摘要
APC先进控制系统是一类基于数学模型的预估控制系统,是用多变量线性模型来描述过程的动态特性、用模型预测过程输出轨迹与希望轨迹的距离作为控制质量指标,求得最优的控制策略。利用先进控制技术满足装置安全平稳操作的要求、提高装置加工能力和高附加值产品收率,是国内外炼化企业普遍采用的技术手段。洛阳石化延迟焦化装置设计加工能力为140×104t/a,该装置采用APC先进控制后,增强了装置的抗干扰能力,提高了装置生产的平稳性,减轻了操作人员的工作负荷。但在焦炭塔预热、切塔、大吹汽等重要操作节点,生产工况变化较大,APC先进控制系统存在一定程度的滞后性,造成控制系统紊乱。根据系统热量和物料变化,提出了操作变量和被控变量在各重要操作节点的设置原则,在不切除APC控制系统的情况下,通过改变变量上、下限数值,来增强装置的抗干扰能力。通过对比APC先进控制系统投用前后的产品质量、关键操作参数,装置实现了卡边控制,目的产品收率、处理能力和装置效益得到提高,分馏系统和吸收稳定系统的稳定性有所增强。
Advanced Process Control（APC） is a forecast control system based on mathematical models,which uses multivariable linear models to characterize the dynamics of processes and models to forecast the distance between process output trajectories and desired trajectories as the quality control indicator to develop the optimal control strategy.Using APC to achieve safe and stable operation of units and to raise the processing capacity of units and the yield of high-value products is the technical approach commonly adopted by both domestic and foreign oil refiners.Sinopec Luoyang Company ’ s delayed coking unit had a designed processing capacity of 140 ×104t/a.After adopting APC,the unit had a stronger capability of resisting interference,which in turn improved the stability of operation of the unit and reduced work load for operators.However,at some key operating points such as preheating,column switching and large steam blow,the operating conditions of the unit changed dramatically.APC had a certain lagging,leading to a disorder of the control system.According to the changes in the quantity of system heat and in the materials used,technicians proposed the principles of setting operating variables and manipulated variables at each key operating point —increasing the unit’ s capability of resisting interference by amending the upper and lower limits of variables without cutting off APC.By comparing the product quality and key operating parameters before and after the introduction of APC,these technicians concluded that the unit achieved ＂border＂ quality control,the yields of target products and the unit’ s processing capacity and efficiency al increased and that the fractionating system and the adsorption system had better stability.
出处
《中外能源》
CAS
2013年第8期76-81,共6页
Sino-Global Energy
关键词
APC先进控制
延迟焦化
操作变量
被控变量
Advanced Process Control
delayed coking
operating variable
manipulated variable
