2015 AIChE Annual Meeting Proceedings

(242a) Numerical Simulation of Delayed Coking Reactor

The delayed coking process is the preferred choice of refiners for bottom of the barrel upgrading due to its inherent capability to handle practically every type of hydrocarbon residua. In the delayed coking process, the oil is transformed into light hydrocarbons and coke, the process is semi-batch because at some point the reactor is filled with coke and has to be discharged. In this work a numerical simulation of a delayed coking reactor at pilot plant scale is performed. The process is modelled with continuity, momentum, volume fractions and energy equations; the reaction is a simple transformation of vacuum residua into light hydrocarbons and coke for which two fluid phases (vacuum residua and light hydrocarbons) and one solid phase (coke) are modeled, the kinetic parameters were obtained with a TGA. The equations are solved numerically by a finite volume discretization, the pressure checkerboard issue is overcome with a staggered grid for velocities, the pressure velocity coupling is performed with a SIMPLEC algorithm which is programmed in C++ code. The result is a dynamic simulation of the formation of products and accumulation of coke in the reactor and the posterior quenching of this coke.