Abstract
Catalytic ammonia decomposition and tar reduction by a Ni catalyst were studied using a feed gas from a pilot-scale pressurized fluidized-bed gasifier. Tests were conducted in a tubular fixed-bed reactor with a space time of about 3 s at 800-900 degreesC and 12 atm. Ammonia removals of 35-95% and light tar conversions of 90-95% were observed. The amount of the light hydrocarbons was found to have a negative effect on the ammonia decomposition. An ammonia concentration in the fuel gas, gas residence time, and catalytic bed temperature also had a significant influence on the ammonia removal efficiency. After the catalyst, CO2 and CO approached equilibrium values,but the content of H-2 and H2O was lower because of reactions with tar. The heating value of the fuel gas remained the same; The gasification efficiency increased by about 10%, mainly because of catalytic tar cracking. Deactivation of the catalyst was not observed in the fuel gas containing 50-150 ppm H2S and about 10 g/Nm(3) tar.
Original language | English |
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Pages (from-to) | 4075-4081 |
Journal | Industrial & Engineering Chemistry Research |
Volume | 39 |
Issue number | 11 |
DOIs | |
Publication status | Published - 2000 |
Subject classification (UKÄ)
- Chemical Engineering