The molecular conversion of complex mixture involves a large number of
species and reactions. The corresponding kinetic model is consist of a
series of ordinary differential equations (ODEs) with severe stiffness,
leading to an exponentially growing computational time. To reduce the
computational time, we proposed a mass-temperature decoupled
discretization strategy for a large-scale molecular-level kinetic model.
The method separates the mass balance and heat balance calculations in
the rigorous adiabatic reactor model and divided the reactor into
several isothermal segments. After discretization, the differential
equations for heat balance can be replaced by algebraic equations
between nodes. We used a molecular-level diesel hydrotreating kinetic
model as the case to validate the proposed method. We investigated the
effects of temperature estimation methods and node number on the
accuracy of the model. A good agreement between the discretization model
and rigorous model was observed while the computational time was
significantly shortened
Iterative methods for solving Riccati differential equations
