THERMAL SCIENCE

International Scientific Journal

Authors of this Paper

External Links

THE MAIN NATURAL LOWS OF HIGH-RATE COAL PYROLYSIS

ABSTRACT
The importance of coal pyrolysis studies for the development of energy technologies is evident, since pyrolysis is the first stage of any process of coal thermal conversion. In combustion, pyrolysis deter mines conditions of coal ignition and the rate of char after-burning; in gasification, pyrolysis determines total yield of gasification products. It must be noted that in modern energy technologies pyrolysis occurs at high rate of coal particle heating (approx. 103 K/s for different fluidized bed, or FB-technologies) or super-high-rate (≥105 K/s for entrained-flow gasification), and in some of them at high pressure. In CETI during last 12 years the detailed study of pyrolysis in FB laboratory-scale PYROLYSIS-D plant and entrained-flow pilot-scale GSP-01 plant, was carried out. In this paper main results of mentioned investigations are given. Kinetic constants for bituminous coals and anthracite high heating rates in entrained flow for high temperatures (≥1500 C and ≥1900 C), and in fluidized bed conditions in temperature range 972-1273 K. In order to describe data obtained in fluidized bed conditions, G-model-based method of calculation of devolatilization dynamics was suited to FB heating conditions. Calculated and experimental kinetic data are in good agreement. The result proves that at FB-pyrolysis conditions intrinsic mass-transfer limitations are negligible and devolatilization is really kinetic-controlled.
KEYWORDS
PAPER SUBMITTED: 2003-06-02
PAPER REVISED: 2003-09-12
PAPER ACCEPTED: 2003-10-11
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2003, VOLUME 7, ISSUE Issue 2, PAGES [77 - 87]
REFERENCES
  1. Radovanović I. Fluidized bed combustion (in Russian), Translation from English language under redaction of E. Schpil'rain, Moscow, Energoastomizdat, 1990.
  2. Solomon P.R., Serio M.A., Suuberg E.M. Coal pyrolysis: experiments, kinetic rates and mechanisms, Prog. En. Comb. Sci. 1992, V18, pp 133-220.
  3. Saranchuk V. I , Butuzova L. F. , Minkova V. N. Thermochemical destruction of bituminous coals (in Russian), Kiev, Naukovaya Dumka, 1993.
  4. Neoh K., Gannon R. Coal volatile yield and element partition in rapid pyrolysis, Fuel. 1984., V.63., P. 1347-1352.
  5. H.Y.Cai et al. , Combustion reactivity and morphological change in coal chars: Effect of pyrolysis temperature, heating rate and pressure, Fuel, 1996, V 75, pp 15-24.
  6. Gryaznov N. S., Coal pyrolysis during coke formation (in Russian), Moscow, Metalurgya 1983
  7. Roskolupa A. I., Chernyavsky N. B., Gasification of high-rank coal and anthracite in high-temperature entrained flow (in Russian), Ecotechnology and saving of natural resources 2003, 3, 8-14.
  8. Chernyavskiy N. B., Dulienko S. G., Kul'chickiy I. B., Two-stage gasification of pulverized coal in the entrained flow: model and calculation of the gasgenerator, (in Russian), Ecotechnology and saving of natural resources, 1997, 4, pp 12-20
  9. Chernyavskiy N.V., Gaponich L.S., Dulienko S.G. Coal Pyrolysis and Combustion in Fluidized Bed at Different Pressures: Experimental Method and Results, 3rd Int. CUSTNET Conf. on Coal Utilis. Sci. and Techn. (Bucharest, May 6-7 1998), Bucharest, 1998, pp 45.1-6
  10. Maystrenko A. Y., Reactions of cokes from utility coals with CO2 and O2 in pressurized bubbling fluidized bed, (in Russian) , Ecotechnology and saving of natural resources, 1997, 3, pp 3-10.
  11. Chernyavskiy N.V., Slowing down of gas evolution during thermocontact coal pyrolysis (in Russian) Applied thermotechnic, 2000, 1, pp 41-48.
  12. Chernyavskiy N.V., Dulienko S. G., Gaponich L.S., Optimization of the operation parameters and emissions from the thermocantact circulating fluidized bed pyrolyser, (in Russian), Ecotechnology and saving of natural resources, 1998, 3, pp 17-20.
  13. Gaponich L. S., Tal'nova L. S., Chernyavsky N.V., Influence of pressure and surrounding gas on gas evolution in thermocantact coal pyrolysis (in Russian Ecotechnology and saving of natural resources, 1998, 2, pp 13-17.

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence