Intelligent Operation Optimization of Distillation Column for Debutanization in Ethylene Process

Based on the strictly mathematical and open formed mechanistic model of distillation column, an intelligent operation optimization method based on reduced SQP(sequential quadratic programming) algorithm used to optimize the debutanization in ethylene process was presented. In the proposed method, the real time characteristics and rationality of operation optimization for debutanizer were considered, and thinking of utilizing the sparse structure, the information of degrees of freedom and the objective’s structure, the reduced SQP algorithm and hybrid automatic differentiation technology were used to solve this problem. Some intelligent rules for accelerating convergence, balancing the objective and infeasibility and dealing with abnormal situations were merged into the reduced SQP algorithm, so the algorithm can make balance between total benefits, solving time and qualification requirement. Computing results demonstrate that the intelligent operation optimization method proposed in the paper is more efficient than the method based on Snopt algorithm and the method based on general reduced SQP algorithm, and it is more fit for the requirement of real time operation optimization.