Determination of the Forms of Nitrogen Released in Coal Tar During Rapid Devolatilization. Semi-annual report, May 1-October 31, 1997

The primary objective of this work is to determine the forms of nitrogen in coal that lead to nitrogen release during devolatilization. Experiments are to be performed in two existing laminar flow reactors available at Brigham Young University, which are both capable of temperatures (up to 2000 K), particle heating rates (104 to 105 K/s), and residence times (up to 500 ms) relevant to conditions commonly encountered in industrial pulverized coal combustors. The forms of nitrogen in coal, char, and tar samples are analyzed using state-of-the-art techniques, including nuclear magnetic resonance (NMR), X-Ray photoelectron spectroscopy (XPS), and high resolution nitrogen-specific chromatography. These sophisticated analysis techniques are being performed in collaboration with other researchers at BYU, the University of Utah, and industrial organizations. Coals have been obtained as a function of rank, including eight coals from the University of Utah that are to be used in pilot scale tests in support of the DOE Coal-2000 HIPPS (High Performance Power Systems) and LEBS (Low- Emission Boiler Systems) programs. Anticipated results from the proposed research are (a) nitrogen release parameters during devolatilization for specific coals pertinent to the HIPPS and LEBS projects, (b) better fundamental understanding of the chemistry of nitrogen release, and (c) a nitrogen release submodel based on fundamental chemistry that may be more widely applicable than existing empirical relationships