원유 정제 산업에서 중요한 위치를 차지하고 있으며 에너지 소비량이 큰 원유증류공정을 대상으로 최적 설계를 수행하였다. 현재 상업가동 중인 150,000 BPSD의 원유증류공정 중 상압 증류탑과 경질 납사 안정기에 대한 수학적 모델을 만들고, 에너지 소비를 최소화하도록 목적함수를 설정함으로써 MINLP 문제를 구성하여 이에 대한 해를 구하였다. 최적화작업을 통하여 최적 원료단과 상압 증류탑의 응축기 및 pumparound의 최적 용량을 얻을 수 있었다. 새로운 설계조건의 경우 탑내의 기/액 흐름이 감소되었으며 상압 증류탑의 응축기 용량이 약 15%정도 감소할 수 있음을 알 수 있었다. 또한 고온의 열을 회수 가능하게 하는 pumparound 용량을 약 37% 증가시킬 수 있었다.
As a crude distillation unit(CDU) is one of the important processes in refinery industries and consumes enormous energy, an optimal design of a CDU was attempted. The target CDU is under commercially operated and its capacity is 150,000 BPSD. The mathematical models for an atmospheric distillation column(ADC) and naphtha stabilizer were established and we formulated the objective function so as to minimize the energy consumption. The optimal feed locations of both the atmospheric distillation column and stabilizer were obtained by solving mixed-integer nonlinear programming problems. The optimal duties of condenser and pumparound in the ADC were determined by the optimization task. In the case of optimal design, vapor and liquid load was apparently decreased and the size of the ADC and the stabilizer was accordingly decreased. The optimal feed tray of ADC and stabilizer were 34 and 14 respectively, and the condenser duty of the ADC was decreased by the amount of 15% and the duty of pumparound, which permits heat recovery, was increased by the degree of 37%.
Seo JW, Kim SJ, Kim KH, Oh M, Lee TH, ASME/JSME Joint Pressure Vessels and Piping Conference, San Diego, California, July 26-30, PVP-Vol. 363, 177, 1998
Biegler LT, Grossmann EI, Westerberg AW, "Systematic Methods of Chemical Process Design," Prentice Hall, 1997