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Nowadays hydrogen demand caused by deep fuel refining and the other sustainable processes leads to utilization of new raw materials. Simultaneously, extensive biodiesel production creates great amount of biomass wastes transcendent over feeding potential of farm animals. One of potentially useful process of hydrogen production from renewable natural sources seems to be partial oxidation (POX) and gasification of biomass material like rape meal from rape oil production. The goal of this work was to develop model of experimental POX reactor located in pilot plant unit of UNIPETROL RPA working with rape meal and fuel oil mixture. Mathematical model consists of two parts. First simulation model was created in process simulator Aspen Plus in form of pseudohomogeneous CSTR to fit reaction kinetics and equilibrium on experimental data. Second CFD simulation model was developed in COSOL Multiphysics (PDE solver by finite element method) to find steady state gas velocity, temperature and concentration profiles inside of gasification reactor. Complicated chemical composition was solved by concept of representative chemical compounds resulting in the same elemental composition as the original raw material. Hydrogen production depends both on oxygen and water steam ratio to biomass and hydrocarbon raw material mixture and also on flow characteristic and internal mixing in the reactor. Distribution of residence time of biomass particles in the reactor affects results due to different rate of consecutive reaction steps: pyrolysis, water gas shift and steam reforming reactions. CFD modeling can help to understand complex phenomena in the reactor.