Abstract
Riser reactor is a key unit in the Fluid Catalytic Cracking (FCC), and it has important influences on increasing the yield coefficient of gas and oil. In this paper, the behaviors of gas-solid two-phase flow in the traditional y-type riser reactor are investigated by numerical simulation. The calculated particle concentration distribution is in good agreement with the experimental data, which verified the advanced models and calculating methods. The non-uniform distribution, such as core-annulus flow, may result in the unreasonable matching relationship of catalyst-to-oil ratio. An optimized riser with cuneal internals is proposed and the comparison of two different structures of riser reactor is presented. The comparison results show that the cuneal internals in the riser both can block effectively the slip down of the particles near wall region and weaken core-annulus flow structure due to the redistribution of particles. The results also prove that the particle concentration distribution becomes uniform along the axial and radial direction in the optimized riser by adding cuneal internals, which would be benefits for the catalytic cracking reactions.
Highlights
Fluid Catalytic Cracking (FCC) plays a crucial role in oil refining industry, especially at aspect of cracking heavy-oil to more valuable light products [1] [2]
Riser reactor is a key unit in the Fluid Catalytic Cracking (FCC), and it has important influences on increasing the yield coefficient of gas and oil
The results prove that the particle concentration distribution becomes uniform along the axial and radial direction in the optimized riser by adding cuneal internals, which would be benefits for the catalytic cracking reactions
Summary
Fluid Catalytic Cracking (FCC) plays a crucial role in oil refining industry, especially at aspect of cracking heavy-oil to more valuable light products [1] [2]. Riser reactor is a key unit, which has many simple geometry, good heat and mass transfer and easy to operate Much attention had been paid to study gas-solid two-phase flow by measuring the particle velocity and concentration. Some researchers found that the factors of the solids flux, the superficial gas velocity and the feedstock injection structure influenced the flow uniformity [5] [6]. Though the gas-solid flow at the pre-lift zone and the feedstock injection zone has attracted plenty of researches [11] [12] [13], less attention is paid to the impact of the uneven distribution in the full-reaction zone. By using CFD simulation, we will find the reasons of non-uniform flow and mixing, and present a novel internal structure to improve the flow uniformity
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
