Simulation And Optimization Research Of Fluid Catalytic Cracking Separation System

As an important process in the secondary processing of oil refining industry,fluid catalytic cracking?FCC?is a significant method to transform heavy oil such as residue,VGO,deasphalted oil,raffinate to high-value light oil products such as dry gas,liquefied petroleum gas?LPG?,stabilized gasoline,diesel and so on,and improve the yield of light oil products and economic benefits.Under sustainable energy development and energy saving and emission reduction of economic society background,it is important to improve the yield of light products and reduce energy consumption of FCC unit.The FCC separation system paly a key role in determing the yield of light products and energy consumption of FCC unit.Therefore,it has the vital significance to simulate and optimize the separation system process of FCC unit.The FCC separation system,composed of closely material and energy contact fractionator and absorption-stabilization process.This article mainly aims at simulation and optimization of FCC separation system,main contents are the followings:?1?Described the research background and significance of FCC separation system,and introduced the research development of fractionator and absorption-stabilization process;?2?Simulated and analysed FCC separation system using powerful process simulation software Aspen Plus,the simulated results agree well with the actual working conditions,established the basis for the further work;?3?On the basis of simulation,established the multi-objective model of maximizing the yield of product,minimizing the energy consumption of FCC separation system with constraints including stabilized gasoline ASTM D86 cut point 100%,light diesel ASTM D86 cut point 95%,dry gas C₃ volume fraction,liquefied petroleum gas C₂,C₅ volume fraction in consideration of multi-product plans.Multi-objective line-up competition algorithm?MOLCA?is employed to solve the model and then the Pareto front is obtained which reveals the influence law of the energy consumption on the yield of product.This work provides reference for FCC separation system in design and operation optimization.?4?In light of high energy consumption of absorption-stabilization process,several feed states of deabsorber are compared,absorper is also analysed and improved.Besides,introduced improvements of stabilizer:saturated liquid feed replace vapor-liquid mixture feed of deethane gasoline and set up intermediate reboiler.This work provides important significance for absorption-stabilization system in design and operation optimization.