Gasification of Wood Sawdust and Other Biomass for Hydrogen Production in Supercritical Water

摘要

Hydrogen is gaining increasing attention as an encouraging future energy. Thermochemcial gasification of biomass in supercritical water has been identified as a promising approach for producing renewable hydrogen. Wood sawdust mixed in sodium carboxymethylcellulose(CMC) was gasified in a tubular flow reactor at a pressure range from 17.5 to 30 MPa and a wall temperature of 650℃ with a reactor residence time of 9-50s. Also, other real biomass feedstock, including rice straw, rice shell, wheat stalk, peanut shell, corn stalk, corn core and broomcorn stalk were gasified successfully in supercritical water. The influence of the main parameters (pressure, temperature, residence time, configuration of the reactor, type of biomass, catalyst and concentration of solution) on biomass gasification was investigated. The results from the experiment of biomass gasification indicate that the gasification efficiency is sensitive to the operating parameters mentioned above, and the product gas is composed of hydrogen, carbon dioxide, methane, carbon monoxide and a small amount of ethane and ethylene. The molar fraction of hydrogen in excess of 40% was reached.