Air−Steam Gasification of Biomass in a Fluidized Bed under Simulated Autothermal and Adiabatic Conditions
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- 作者：Manuel Campoy ; Alberto Gó ; mez-Barea ; Angel L. Villanueva ; Pedro Ollero
- 刊名：Industrial & Engineering Chemistry Research
- 出版年：2008
- 出版时间：August 20, 2008
- 年：2008
- 卷：47
- 期：16
- 页码：5957-5965
- 全文大小：374K
- 年卷期：v.47,no.16(August 20, 2008)
- ISSN：1520-5045
文摘
Biomass gasification tests with air−steam mixtures were conducted in a bubbling fluidized-bed (FB) gasification pilot plant. The effect of steam addition on the performance of gasification was studied for different air-to-biomass ratios and biomass throughputs. The reactor was operated near adiabatic conditions, with the aim of reproducing the behavior of full-scale FB units. The temperature of the air−steam mixture was fixed at 400 °C for all tests, a value that can be achieved by energy recovery from the off-gas without tar-condensing problems. The stoichiometric ratio (ratio of actual to stoichiometric air flow rates) and steam-to-biomass flow rate ratio were varied from 0.19 to 0.35 and from 0 to 0.45, respectively. It is shown that the proper selection of operating conditions makes it possible to increase the gasification efficiency from 40% to 60%, while maintaining the low heating value of the gas at around 5 MJ/Nm3. In addition, an appreciable increase of char and tar conversion is achieved. The air−steam gasification concept explored in this work is an interesting option for the improvement of direct air-blown biomass gasification because it can improve the process efficiency considerably without significantly increasing capital costs.