Gaseous organic emissions during air gasification of woody waste: effect of bed agglomeration/defluidization

This study investigated the effects of temperature and the use of additives on the distribution of gaseous products (H-2, CO, CO2, and CH4) and organic pollutants (BTEX and PAHs) during the fluidized bed gasification of woody waste in bed agglomeration/defluidization processes. The results indicated that the hydrogen content increased with an increase in temperature. However, the concentrations of CO, CO2, and CH4 decreased. Moreover, the concentrations of BTEX were significantly influenced by temperature, but the concentrations of PAHs were stable at approximately 100,000 mu g/Nm(3). On the other hand, the addition of CaO and Al2O3 enhanced the production of hydrogen. Then, the emission concentrations of both organics increased with time and decreased with the occurrence of agglomeration. The PAH emission increased dramatically when only SiO2 was present, but PAHs were adsorbed when CaO and Al2O3 were added during the defluidization process. (C) 2014 Elsevier B.V. All rights reserved.