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Full-Text Articles in Chemical Engineering
Simulation Of Coal Pyrolysis In Plasma Jet By Cpd Model, Yajun Tian, Kechang Xie, Suyu Zhu, Thomas H. Fletcher
Simulation Of Coal Pyrolysis In Plasma Jet By Cpd Model, Yajun Tian, Kechang Xie, Suyu Zhu, Thomas H. Fletcher
Faculty Publications
Reaction of coal in a plasma jet is complex and extremely rapid, and acetylene and carbon monoxide are the main products in the pyrolysis gas. Coal pyrolysis is assumed as the first step reaction when coal is injected into hot plasma jet with initial average temperature of 3700 K. Chemical percolation devolatilization (CPD) is employed first to simulate this procedure in mechanism. The calculation results indicate coal pyrolysis rate in plasma jet is very fast and the retention time of coal staying in reactor is only several milliseconds. Comparing the calculation with experiment result, it was concluded that the CPD …
13-C Nmr Analysis Of Soot Produced From Model Compounds And A Coal, Mark S. Solum, Adel F. Sarofim, Ronald J. Pugmire, Thomas H. Fletcher, Haifeng Zhang
13-C Nmr Analysis Of Soot Produced From Model Compounds And A Coal, Mark S. Solum, Adel F. Sarofim, Ronald J. Pugmire, Thomas H. Fletcher, Haifeng Zhang
Faculty Publications
Soot samples, including the associated organics, produced from an Illinois No. 6 coal (five samples) and two model compounds, biphenyl (three samples) and pyrene (two samples), have been studied by 13C NMR methods. The coal soot data served as a guide to selection of the temperature range that would be most fruitful for investigation of the evolution of aerosols composed of soot and tars that are generated from model compounds. The evolution of the different materials in the gas phase followed different paths. The coal derived soots exhibited loss of aliphatic and oxygen functional groups prior to significant growth …
Transformations Of Coal-Derived Soot At Elevated Temperature, Thomas H. Fletcher, Jim Rigby, Jinliang Ma, Brent W. Webb
Transformations Of Coal-Derived Soot At Elevated Temperature, Thomas H. Fletcher, Jim Rigby, Jinliang Ma, Brent W. Webb
Faculty Publications
Coal pyrolysis experiments were performed in the post-flame region of a CH4/H2/air flat-flame burner operating under fuel-rich conditions, where the temperature and gas compositions were similar to those found in the near-burner region of an industrial pulverized coal-fired furnace. Volatiles released from the coal particles formed a cloud of soot particles surrounding a centrally fed coal/char particle stream. Soot samples were collected from the cloud at different residence times using a water-cooled, nitrogen-quenched probe. The soot samples were then analyzed for their elemental compositions of carbon, hydrogen, nitrogen, sulfur, and (by difference) oxygen plus inorganic matter. …
Nitrogen Transformations During Secondary Coal Pyrolysis, Haifeng Zhang, Thomas H. Fletcher
Nitrogen Transformations During Secondary Coal Pyrolysis, Haifeng Zhang, Thomas H. Fletcher
Faculty Publications
A CO/H2/O2/N2 flame was operated under fuel-rich conditions in a flat flame reactor to provide a high-temperature, oxygen-free environment to study secondary reactions of coal volatiles. The distributions of fuel nitrogen in the devolatilization products of four coals, ranging from high volatile bituminous to lignite, were obtained at gas temperatures ranging from 1159 to 1858 K. It was found that the initial nitrogen released was contained almost exclusively in the tar for all coals. Release of nitrogen from the char as light gases started at a later stage than tar nitrogen release. During secondary reactions, …