. Influence of H2O, CO2 and O-2 addition on biomass gasification in entrained flow reactor conditions: Experiments and modelling. Fuel, Elsevier, 2016, 166, pp.166-178. 10 Experiments were modelled with a 1D-model using detailed chemical scheme. Gas, char, tar + soot were satisfactorily simulated in the whole range of conditions. ysis reaction, gas phase reaction with a detailed chemical scheme (176 species, 5988 reactions), char gasification by steam and CO 2 and soot formation. H 2 O or CO addition has no influence on gasification product yields at 800 and 1000 °C, while at 1200 and 1400 °C the char gasification is significantly enhanced and soot formation is certainly inhibited by OH radical which reacts with soot precursors. The modification of output gas phase composition is mostly due to WGS reaction which reaches thermodynamic equilibrium from about 1200 °C. As expected, O 2 has a significant influence on gas and tar yields through combustion reactions. Char and soot yields decrease as ER increases. The GASPAR model allows a good prediction of gas and char and gives relevant evolution of soot and tar yields on the large majority of conditions studied.

International audienceWoody biomass fast pyrolysis in Entrained Flow Reactor (EFR) is studied both with experiments in a lab-scale drop tube reactor (DTR) and simulations with a 1-D model. The parameters of the study are temperature (450-600 degrees C), woody biomass particle size (370-640 mu m) and gas residence time (12.6-20.6 s). The most critical phenomena affecting the bio-oil yield are considered in the model: heating of the biomass particles, slip velocity of the biomass particles varying with biomass/char properties, biomass pyrolysis and tar cracking. The analyses of all products - char, bio-oil and gas - also brought information on the advancement of the pyrolysis and cracking for the different tests. The reactor temperature and particle size were found to have a major influence on the pyrolysis product distribution. The production of bio-oil reaches a maximum of 62.4 wt.% at 500 degrees C for the 370 mm particles. The particle conversion advancement is then estimated at 94% at the reactor exit. The bio-oil yield is lower at higher temperatures for a constant particle size due to tar cracking. At 550 degrees C, increasing the particle size from 370 mm to 640 mu m induces a decrease of the bio-oil yield from 48.3 to 34.8 wt.%, which was shown to be due to incomplete pyrolysis of the particles, because of a too short residence time as well as a too long heating time of particles. The pyrolysis conditions - temperature, particle size - were not found to have any significant influence on the bio-oil properties, such as acidity. (C) 2017 Elsevier Ltd. All rights reserved