title: NH3 formation and destruction during the gasification of coal in oxygen and steam.
abstract: This study was conducted to investigate the formation and destruction of NH3 during the gasification of coal in atmospheres containing O2 and steam. A Victorian brown coal was gasified in a novel bench-scale fluidized-bed/ fixed-bed reactor at 800 degrees C in atmospheres containing 2000 ppm O2, 15% H2O, or 2000 ppm O2 + 15% H2O. A NH3 standard gas was also used to study the destruction of NH3 in the gas phase and through gas-solid interactions. Sand, char, and coal ash were all found to enhance the destruction of NH3. An atmosphere containing O2 alone does not favor the conversion of char-N into NH3 but favors the destruction of NH3 through various mechanisms. The introduction of H2O into the gasification system greatly favors the conversion of char-N into NH3 and inhibits the destruction of NH3. The formation and destruction of NH3 in an atmosphere containing 15% H20 was similar to that in an atmosphere containing 15% H20 and 2000 ppm 02, indicating the dominant effects of steam in the formation and destruction of NH3 in a gasifier.
authors.affiliation: Department of Chemical Engineering, P.O. Box 36, Monash University, VIC 3800, Australia.
authors.forename: Lachlan J
authors.initials: LJ
authors.lastname: Mckenzie
authors.forename: Fu-Jun
authors.initials: FJ
authors.lastname: Tian
authors.forename: Chun-Zhu
authors.initials: CZ
authors.lastname: Li
mesh_terms: D000641:Ammonia / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry; D002606:Charcoal / Q000737:chemistry; D003031:Coal; D060729:Coal Ash; D009569:Nitric Oxide / Q000032:analysis; D010100:Oxygen / Q000737:chemistry*; D052638:Particulate Matter / Q000737:chemistry; D013227:Steam; D013696:Temperature; D013997:Time Factors