Oxidative pyrolysis of wood chips and of wood pellets in a downdraft continuous fixed bed reactor

FUEL

卷:196

Article

Daouk, Elias^1,2,3  Van de Steene, Laurent¹  Paviet, Frederic³  Martin, Eric¹  Valette, Jeremy¹  Salvador, Sylvain² 

[1] CIRAD UR BioWooEB, 73 Ave Jean Francois Breton, F-34398 Montpellier 5, France

[2] CNRS UMR 5203, RAPSODEE, Mines Albi, Campus Jarlard, F-8101309 Albi Cedex 09, France

[3] Univ Nantes, UMR 6144 CNRS, GEPEA, Ecole Mines Nantes, 4 rue Alfred Kastler,BP 20722, F-44307 Nantes 3, France

关键词: Oxidative pyrolysis;    Fixed-bed;    Biomass;    Smoldering;    Yields of products;   

DOI  :  10.1016/j.fuel.2017.02.012

来源: Elsevier

【 摘 要 】

In air staged gasification and advanced carbonization processes, oxidative pyrolysis occurs in downdraft continuous fixed bed reactors. An oxidation zone separates the virgin fuel from the resulting char and propagates upward. Here, the oxidation zone was stabilized at a fixed elevation in a 20 cm I.D. fixed bed reactor using wood chips or wood pellets. In controlled continuous operating mode, we investigated the impact of air flux and bed bulk density on the behavior of the oxidation zone in terms of wood consumption, and yields of chit., gas and tars. An air:wood mass ratio of 0.7 was measured and in our operating conditions, and was not sensitive to air mass flux and bed density. With oxidative pyrolysis, yields of organic condensates were lower than with allothermal pyrolysis, whereas the production of pyrolysis water and permanent gases increased. Finally, the oxidation zone was shown to be flat and horizontal in a wood pellet bed but inclined in a wood chip bed. (C) 2017 Elsevier Ltd. All rights reserved.

【 授权许可】

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