Abstract
This study proposes a gas-cleaning process for the simultaneous removal of sulfur compounds, tar, and particles from biomass-gasified gas using Fe-supported activated carbon and a water-gas shift reaction. On a laboratory scale, the simultaneous removal of H2S and COS was performed under a mixture of gases (H2/CO/CO2/CH4/C2H4/N2/H2S/COS/steam). The reactions such as COS + H2 → H2S + CO and COS + H2O → H2S + CO2 and the water-gas shift reaction were promoted on the Fe-supported activated carbon. The adsorption capacity with steam was higher than that without steam. On a bench scale, the removal of impurities from a gas derived from biomass gasification was investigated using two activated filters packed with Fe-supported activated carbon. H2S and COS, three- and four-ring polycyclic aromatic hydrocarbons (PAHs), and particles were removed and a water-gas shift reaction was promoted through the first filter at 320–350 °C. The concentrations of H2S and COS decreased to less than 0.1 ppmv. Particles and the one- and two-ring PAHs, except for benzene, were then removed through the second filter at 60–170 °C. The concentration of tar and particles decreased from 2428 to 102 mg Nm−3 and from 2244 to 181 mg Nm−3, respectively.
Highlights
To prevent the depletion of fossil fuels and control global warming, technologies for converting biomass to energy are being developed
Among the conversion technologies for these liquid fuels, the primary focus recently has been on a biomass-to-liquid (BTL) process, which involves the production of syngas (CO + H2) by biomass gasification, and of liquid fuels by a Fischer–Tropsch (FT) synthesis reaction [1,2]
If the product gas is to be compressed in order to increase the liquid fuel yield, tar and particles have to be removed for steady operation
Summary
To prevent the depletion of fossil fuels and control global warming, technologies for converting biomass to energy are being developed. Before the product gas derived from biomass gasification can be applied to FT catalysts, it is necessary to remove sulfur compounds from the product gas in order to maintain FT catalytic performance. A wet gas-cleaning process using scrubbers is applied to the gasification process of coal and biomass [6,7] This method is complex and the capital cost is relatively high. Much research about dry gas-cleaning as it applies to the BTL process has been reported; reports about catalysts and their lifetime using a real gas derived from biomass gasification are not enough even on a laboratory scale test. In the present study, effective adsorbents for sulfur compounds are investigated on a laboratory scale using Fe-supported activated carbon. Fe-supported activated carbon is applied to remove tar, particles, and sulfur compounds in a product gas derived from biomass gasification. On the basis of the obtained results, the possibility of applying the simultaneous hot gas-cleaning process to the total BTL process using Fe-supported carbon is discussed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
