Use of Rheometry and 1H NMR Spectroscopy for Understanding the

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Energy & Fuels 2004, 18, 1250-1256

Use of Rheometry and 1H NMR Spectroscopy for Understanding the Mechanisms behind the Generation of Coking Pressure Karen M. Steel,* Miguel Castro Diaz, John W. Patrick, and Colin E. Snape Nottingham Fuel and Energy Centre, School of Chemical, Environmental and Mining Engineering, Nottingham University, Nottingham, NG7 2RD, United Kingdom Received September 19, 2003. Revised Manuscript Received May 20, 2004

The fluid phase which forms during carbonization of a range of coals was studied using rheometry and 1H NMR spectroscopy to study the mechanisms behind the generation of excessive wall pressures during coking. It is proposed that high coking pressures are generated for low volatile matter coals when the temperature of maximum fluidity (Tmf) is >465 °C, the minimum complex viscosity (η*) is >105 Pa s, the percentage of mobile 1H (fluid phase) is