Department of Chemical and Environmental Engineering, University of the Basque Country UPV/EHU, Nieves Cano 12, Vitoria-Gasteiz, 01006, Spain.
Department of Chemical Engineering, University of the Basque Country UPV/EHU, P.O. Box 644, E48080, Bilbao, Spain.
J Environ Manage. 2023 Dec 1;347:119071. doi: 10.1016/j.jenvman.2023.119071. Epub 2023 Oct 4.
The pyrolysis and in line steam reforming of different types of representative agroforestry biomass wastes (pine wood, citrus wastes and rice husk) was performed in a two-reactor system made up of a conical spouted bed and a fluidized bed. The pyrolysis step was carried out at 500 °C, and the steam reforming at 600 °C with a space time of 20 g min g and a steam/biomass ratio (S/B) of 4. A study was conducted on the effect that the pyrolysis volatiles composition obtained with several biomasses has on the reforming conversion, product yields and H production. The different composition of the pyrolysis volatiles obtained with the three biomasses studied led to differences in the initial activity and, especially, in the catalyst deactivation rate. Initial conversions higher than 99% were obtained in all cases and the H production obtained varied in the 6.7-11.2 wt% range, depending on the feedstock used. The stability of the catalysts decreased depending on the feedstock as follows: pine wood ≫ citrus waste > rice husk. A detailed assessment of the mechanisms of catalyst deactivation revealed that coke deposition is the main cause of catalyst decay in all the runs. However, the volatile composition derived from the pyrolysis of citrus waste and rice husk involved the formation of an encapsulating coke, which severely blocked the catalyst pores, leading to catalyst deactivation during the first minutes of reaction.
在由锥形喷动床和流化床组成的两反应器系统中，对不同类型的典型农林生物质废物（松木、柑橘废物和稻壳）进行了热解和在线蒸汽重整。热解步骤在 500°C 进行，蒸汽重整在 600°C 进行，停留时间为 20 g min g，蒸汽/生物质比（S/B）为 4。研究了几种生物质获得的热解挥发分组成对重整转化率、产物收率和 H 产量的影响。所研究的三种生物质获得的热解挥发分的不同组成导致了初始活性的差异，特别是催化剂失活速率的差异。在所有情况下，初始转化率都高于 99%，H 产量在 6.7-11.2 wt%范围内变化，这取决于所用的原料。催化剂的稳定性取决于原料，如下所示：松木≫柑橘废物>稻壳。对催化剂失活动力学的详细评估表明，焦炭沉积是所有运行中催化剂衰减的主要原因。然而，源自柑橘废物和稻壳热解的挥发性成分涉及形成包封焦炭，这严重阻塞了催化剂孔，导致在反应的最初几分钟内催化剂失活。
