Pyrolysis and gasification of coal at high temperatures
Abstract
We made considerable progress towards developing a thermogravimetric reactor with in-situ video imaging capability (TGA/IVIM). Such a reactor will allow us to observe macroscopic changes in the morphology of pyrolyzing particles and thermal ignitions while monitoring at the time the weight of pyrolyzing or reacting samples. The systematic investigation on the effects of pyrolysis conditions and char macropore structure on char reactivity continued. Pyrolysis and gasification experiments were performed consecutively in our TGA reactor and the char reactivity patterns were measured for a wide range of temperatures (400 to 600[degrees]C). These conditions cover both the kinetic and the diffusion limited regimes. Our results show conclusively that chars produced at high pyrolysis heating rates (and, therefore, having a more open cellular macropore structure) are more reactive and ignite more easily than chars pyrolyzed at low heating rates. These results have been explained using available predictions from theoretical models. We also investigated for the first time the effect of coal particle size and external mass transfer limitations on the reactivity patterns and ignition behavior of char particles combusted in air. Finally, we used our hot stage reactor to monitor the structural transformations occurring during pyrolysis via a video microscopy system. Pyrolysis experimentsmore »
- Authors:
- Publication Date:
- Research Org.:
- Rice Univ., Houston, TX (United States). Dept. of Chemical Engineering
- Sponsoring Org.:
- USDOE; USDOE, Washington, DC (United States)
- OSTI Identifier:
- 6782852
- Report Number(s):
- DOE/PC/79930-T16
ON: DE93007682
- DOE Contract Number:
- FG22-87PC79930
- Resource Type:
- Technical Report
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 01 COAL, LIGNITE, AND PEAT; CHARS; GASIFICATION; POROSITY; COAL; PYROLYSIS; CHEMICAL REACTION KINETICS; COAL GASIFICATION; HEATING RATE; IGNITION; MATHEMATICAL MODELS; MICROSCOPY; PARTICLE SIZE; PROGRESS REPORT; SWELLING; TEMPERATURE DEPENDENCE; THERMAL GRAVIMETRIC ANALYSIS; CARBONACEOUS MATERIALS; CHEMICAL ANALYSIS; CHEMICAL REACTIONS; DECOMPOSITION; DOCUMENT TYPES; ENERGY SOURCES; FOSSIL FUELS; FUELS; GRAVIMETRIC ANALYSIS; KINETICS; MATERIALS; PYROLYSIS PRODUCTS; QUANTITATIVE CHEMICAL ANALYSIS; REACTION KINETICS; SIZE; THERMAL ANALYSIS; THERMOCHEMICAL PROCESSES; 010404* - Coal, Lignite, & Peat- Gasification; 010409 - Coal, Lignite, & Peat- Pyrolysis & Carbonization- (1987-)
Citation Formats
Zygourakis, K. Pyrolysis and gasification of coal at high temperatures. United States: N. p., 1990.
Web. doi:10.2172/6782852.
Zygourakis, K. Pyrolysis and gasification of coal at high temperatures. United States. https://doi.org/10.2172/6782852
Zygourakis, K. 1990.
"Pyrolysis and gasification of coal at high temperatures". United States. https://doi.org/10.2172/6782852. https://www.osti.gov/servlets/purl/6782852.
@article{osti_6782852,
title = {Pyrolysis and gasification of coal at high temperatures},
author = {Zygourakis, K},
abstractNote = {We made considerable progress towards developing a thermogravimetric reactor with in-situ video imaging capability (TGA/IVIM). Such a reactor will allow us to observe macroscopic changes in the morphology of pyrolyzing particles and thermal ignitions while monitoring at the time the weight of pyrolyzing or reacting samples. The systematic investigation on the effects of pyrolysis conditions and char macropore structure on char reactivity continued. Pyrolysis and gasification experiments were performed consecutively in our TGA reactor and the char reactivity patterns were measured for a wide range of temperatures (400 to 600[degrees]C). These conditions cover both the kinetic and the diffusion limited regimes. Our results show conclusively that chars produced at high pyrolysis heating rates (and, therefore, having a more open cellular macropore structure) are more reactive and ignite more easily than chars pyrolyzed at low heating rates. These results have been explained using available predictions from theoretical models. We also investigated for the first time the effect of coal particle size and external mass transfer limitations on the reactivity patterns and ignition behavior of char particles combusted in air. Finally, we used our hot stage reactor to monitor the structural transformations occurring during pyrolysis via a video microscopy system. Pyrolysis experiments were videotaped and particle swelling and the particle ignitions were determined and analyzed using digitized images from these experiments.},
doi = {10.2172/6782852},
url = {https://www.osti.gov/biblio/6782852},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 1990},
month = {Mon Jan 01 00:00:00 EST 1990}
}