提出一种考虑了可控性的换热网络旁路设计法。基于稳态模型增益的定量计算,推导换热网络稳态数学模型的求解过程,从可控性分析的角度逐一求解换热网络的非方相对增益矩阵,从中确定最优的旁路位置,使被控变量具有较高的可控性。突破相对增益矩阵仅用于控制配对的常规范畴,提出一种通过逐次求解换热网络非方相对增益矩阵优化选取最优旁路设置的方法,并给出了设置旁路的若干准则,以简化求算过程。分析稳态工作点变化后的情况,表明工况变化不影响上述得出的旁路设置。该法适用于大型复杂换热网络,满足生产控制要求,并能保证整个换热网络具有较高的可控性。以某常减压蒸馏装置脱盐前换热网络为例,验证方法的可行性和有效性。
A controllable bypass optimal design method is presented.The way to establish a heat exchanger networks(HEN)model was derived for the quantitative analysis of relative gain array(RGA).From the point of view of controllability,a HEN non-square RGA(ns-RGA)was calculated iteratively,and then the optimal bypass location was determined to ensure a more controllable HEN.Generically,RGA was used to select appropriate manipulated variables for target temperatures,but it was a breakthrough here and a novel optimal bypass location method was presented by iteratively calculating the HEN ns-RGA.Some guidelines were given to simplify the work.A case analysis indicated that changes of normal operation state of the HEN would not impact the bypasses location,which was derived from the above method.This method was adaptable to complex HEN,and could guarantee a more controllable HEN for production.A case study demonstrated the effectiveness and feasibility of the method proposed in this paper.