Study On Model And Simulation Of Complex Crude Distillation Column

Petroleum industry is one of the pillar industries in China.Accurate and reliable simulation of complex crude distillation column has great significance to optimize the refining process and improve the safety and environmental protection level of enterprises.Typical complex crude distillation column such as atmospheric column,catalytic cracking,delayed coking main fractionator,etc,need to deal with complex components,multiple side drawoff,pumparounds and strippers.Traditional algorithms often regard the main column and strippers as one column system when dealing with such problems,multiple tear streams were need to calculate,it is prone to cause more iterations,and large consumption of computer memory.Therefore,some scholars used equation oriented method to simulate complex crude distillation column,and proposed corresponding algorithms such as bubble point-sum rate method(BP-SR)and inside-out method.Although these algorithms have solved the above problems to a certain extent,there are still some disadvantages such as the complexity of the computational model and the inability to guarantee stable convergence.Based on the present situation,this subject has extensively studied the literature of the complex crude distillation column and the function of the crude oil distillation module in the commercial process simulation software,improved algorithm and developed a general simulation program follow the CAPE-OPEN standard on this basis.First,adoped equation oriented idea,the furnace,strippers and main tower were regarded as a whole to establish the mathematical model,and considering the influence of different feed modes and plate efficiency.Then,aimed at the shortcoming of the traditional inside-out method,which can not solve directly when stipulate the stipper production flow,learned the sum rate method to improve the algorithm,so that it can converge steadily.Finally,the atmospheric and vacuum and the catalytic cracking fractionation devices were used to verify the results,The calculation results of the developed model algorithm were compared with the production data and the Aspen simulation results.The results showed that the key parameters of the tower equipment were basically consistent with the actual production data,the maximum error was 4.42%.the temperature,vapor-liquid load trends of each column stage and ASTM distillation data were consistent with Aspen's modeling results,and the relative error is within 5%.The reliability of the model and algorithm is proved.The development of the general unit module of the complex crude distillation column not only laid a firm foundation for the improvement of the steady-state distillation column algorithm,but also promotes the in-depth research and promotion of process simulation technology.