FLASHCHAIN® is the most thoroughly validated devolatilization mechanism ever devised, simply because a fuel’s proximate and ultimate analyses are the only sample-specific input data requirements. Published validation work covers at least 300 different coals from all geographical regions worldwide, and over 100 raw and torrefied biomass samples. NEA’s recent expansion of FLASHCHAIN® for biomass analyzes cylindrical particles to accurately depict how variations in a fuel’s aspect ratio affect its devolatilization behavior. Also, the new biomass analysis is the first of any kind to accurately depict how torrefaction suppresses total and tar yields.
FLASHCHAIN® is very popular in the US and Japan and is widely recognized for its accuracy and computational expedience. NEA’s current FLASHCHAIN®-based software products are PC Coal Lab®, which simulates complete histories for pyrolysis, combustion, gasification, and hydrogasification at any operating conditions, and EPRI’s NOX LOI Predictor, which predicts NOX and unburned carbon emissions from full-scale utility boilers. Besides offering the world’s best computer software to predict fuel quality impacts, NEA also offers consulting services based on FLASHCHAIN® and FLASHCHAIN®-based computer products, and develops custom computer packages according to our clients’ specifications.
S. Niksa, G. Liu, and R. H. Hurt, “Coal Conversion Submodels for Design Applications at Elevated Pressures. Part I. Devolatilization and Char Oxidation,” Prog. Energy Combust. Sci., 29(5):425-477 (2003).
S. Niksa, “Process Chemistry of Coal Utilization: Impacts of Coal Quality and Operating Conditions,” Woodhead Publishing, Elsevier, London, ISBN 978-0-12-818713-5, Nov. 2019.
Formal mathematical derivations and validations with test data on coals are covered in the FLASHCHAIN® series:
S. Niksa and A. R. Kerstein, “Flashchain Theory for Rapid Coal Devolatilization Kinetics. 1. Formulation,” Energy and Fuels, 5(5): 647-664 (1991a).
S. Niksa, “Flashchain Theory for Rapid Coal Devolatilization Kinetics. 2. Impact of Operating Conditions,” Energy and Fuels, 5(5): 647-664 (1991b).
S. Niksa, “Flashchain Theory for Rapid Coal Devolatilization Kinetics. 3. Modeling the Behavior of Various Coals,” Energy and Fuels, 5(5): 647-664 (1991c).
S. Niksa, “Flashchain Theory for Rapid Coal Devolatilization Kinetics. 4. Predicting Ultimate Yields from Ultimate Analyses Alone,” Energy and Fuels, 8: 659 (1994b).
S. Niksa, “Flashchain Theory for Rapid Coal Devolatilization Kinetics. 5. Interpreting Rates of Devolatilization for Various Coal Types and Operating Conditions,” Energy and Fuels, 8: 671 (1994c).
S. Niksa, “Flashchain Theory for Rapid Coal Devolatilization Kinetics. 6. Predicting the Evolution of Fuel Nitrogen from Various Coals,” Energy and Fuels, 9: 467-478 (1995b).
S. Niksa, “Flashchain Theory for Rapid Coal Devolatilization Kinetics. 7. Predicting the Release of Oxygen Species from Various Coals,” Energy and Fuels, 10: 173-187 (1996).
S. Niksa, “FLASHCHAIN Theory for Rapid Coal Devolatilization Kinetics. 8. Modeling the Release of Sulfur Species from Various Coals,” Energy Fuels, 31:4925-38 (2017a).
S. Niksa, “FLASHCHAIN Theory for Rapid Coal Devolatilization Kinetics. 9. Decomposition Mechanism for Tars from Various Coals,” Energy Fuels, 31:9080-93 (2017b).
S. Niksa, “FLASHCHAIN Theory for Rapid Coal Devolatilization Kinetics. 10. Hydropyrolysis Yields from Various Coals,” Energy Fuels, 32:384-95 (2018).
S. Niksa, “FLASHCHAIN Theory for Rapid Coal Devolatilization Kinetics. 11. Tar Hydroconversion Mechanism for Various Coals,” Energy Fuels, 32: 7569 – 84 (2018).
The analysis for raw and torrefied biomass is covered in:
S. Niksa, “Predicting the Rapid Devolatilization of Diverse Forms of Biomass with bio-FLASHCHAIN®,” Proc. Combust. Inst. 28: 2727-2733 (2000).
S. Niksa, “bio-FLASHCHAIN® Theory for rapid devolatilization of biomass. 1. Lignin devolatilization,” Fuel, 263:116649 (2020).
S. Niksa, “bio-FLASHCHAIN® Theory for rapid devolatilization of biomass. 2. Predicting total yields for torrefied woods,” Fuel, 263:116645 (2020).
S. Niksa, “bio-FLASHCHAIN® Theory for rapid devolatilization of biomass. 3. Predicting total yields for torrefied grasses and agricultural residues,” Fuel, 263:116646 (2020).
S. Niksa, “Predicting combustion characteristics of raw and torrefied biomass with bio-FLASHCHAIN® and CBK/E,” Fuel, in preparation (2020).
Mechanisms for tar decomposition and hydroconversion are covered in:
S. Niksa, “A reaction mechanism for tar decomposition at moderate temperatures with any coal type,” Fuel, 193:467-76 (2017).
S. Niksa, “FLASHCHAIN® Theory for Rapid Coal Devolatilization Kinetics. 9. Decomposition Mechanism for Tars from Various Coals,” Energy Fuels, 31:9080-93 (2017).
S. Niksa, “FLASHCHAIN® Theory for Rapid Coal Devolatilization Kinetics. 11. Tar Hydroconversion Mechanism for Various Coals,” Energy Fuels, 32: 7569 – 84 (2018).
Niksa, S. “Predicting nitrogen release during coal tar decomposition,” Proc. Combust. Inst. 37:2765-72 (2019).
S. Niksa, “Predicting ultimate soot yields from any coal,” Proc. Combust. Inst. 37:2757-64 (2019).