Gasifying agent

Dried coal is pneumatically conveyed to feed bins, pressurized through lockhoppers, and fed to the refractory-lined fluidized-bed gasifier vessel by variable-speed screws. The gasifying agent, mixed oxygen and steam, is fed near the bottom of the gasifier. The bed operates at 2.5 MPa (25 bar) and... 

CO2 is much less volatile than CO (p. 306). It is a major industrial chemical but its uses, though occasionally chemical, more frequently depend on its properties as a refrigerant, as an inert atmosphere, or as a carbonating (gasifying) agent in drinks and foam plastic (see Panel). 

Gil, J., Corella, J., Aznar, M. P., Caballero, M. A. (1999a) Biomass Gasification in Atmospheric and Bubbling Fluidized Bed Effect of the Type of Gasifying Agent on the Product Distribution. Biomass Bioenergy, 17, 389-403. 

The present work has the novelty of introducing CO2 as a gasifying agent. Pyrolysis and steam gasification are processes currently being investigated to obtain... 

Typical amount of feed material was about 500 mg willow wood and 350 mg char. The particle size of the feed material used was less than 0.7 mm. As gasifying agent hydrogen, carbon dioxide, steam, or helium was used. 

Type of gasifying agent—whether steam or hydrogen. Feed gas/wood ratio. 

The observations that at higher system pressures, temperature influences methane concentration in the gas phase much more than whether steam or hydrogen is the gasifying agent, and the much higher-than-equilibrium methane concentrations suggests that methane probably arises from the primary devolatilization process rather than subsequent solid phase reactions. 

The gasification techniques can be distinguished related to different criteria such as reactor type (fixed bed or fluidized bed), gasifying agent (air, oxygen, or steam), heat supply into the reactor (directly or indirectly heated) and reactor... 

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