Hydrocracking is a crucial refinery process that transforms
heavy
molecules (i.e., vacuum gas oil (VGO)) into lighter and highly valued
products such as naphtha, kerosene, and diesel. It is a two-step process.
The hydrotreatment (HDT) reactor uses a more robust catalyst, which
essentially serves to remove heteroatoms from the VGO feed in order
to satisfy product quality constraints and avoid poisoning the more
delicate zeolite-based HCK catalysts. The second hydrocracking (HCK)
reactor uses a commercial zeolite catalyst with a carefully selected
balance of acid and metallic sites. For hydrotreatment simulation,
the kinetic model is decomposed in several ODEs (ordinary differential
equations). Catalyst vendors develop more and more catalysts. For
each new catalyst (new generation), the kinetic parameters must be
refitted. This task is costly and time-consuming. In this article,
in order to reduce the required number of experimental points, a Bayesian
transfer approach is proposed to fit the parameters of catalyst (n + 1), using the past knowledge of catalyst (n) to add more information. A method for the choice of the prior is
proposed and can be used for any type of parametric model. This approach
is applied and shows an improvement in the prediction performance
and robustness compared to a classical fitting method. In our case,
only 10 pilot plant points on catalyst (n + 1) are
requested to refit an HDN kinetic model.