Effects of preoxidation on pyrolysis behavior and resultant char structure of caking coals

Conference · Fri Jan 01 04:00:00 EST 1982 · Prepr. Pap. - Am. Chem. Soc., Div. Fuel Chem.; (United States)

OSTI ID:6690907

Maloney, D J; Jenkins, R G

Coal gasification processes may be divided into two stages. They are, the initial rapid release of volatile matter and the relatively slow gasification of the residual char. These two processes are not, however, totally independent because the heat treatment conditions under which coal pyrolysis occurs determine, to a large extent, the structure and reactivity of the remaining char. The work described here is concerned with the utilization of bituminous (caking) coals in dilute phase, rapid heating gasification and combustion system. Two highly caking coals were pyrolyzed in an entrained flow tube furnace system and devolatilization kinetics determined for each coal at temperatures of 900 and 1000/sup 0/C. Structural properties of the chars were then analyzed. In addition, the effects of mild preoxidation of these coals upon their subsequent pyrolysis behavior were examined. Samples of each coal were oxidized to various levels prior to heat treatment. The sharp contrast in macroscopic properties of the chars collected in this study give rise to several important questions regarding char gasification. Varying heat treatment conditions and coal feed stocks give rise to chars of widely varying structure. In order to understand the behavior of these materials in subsequent gasification steps a more detailed analysis of char structure is required. At present microstructural properties (surface areas, porosities) of the chars generated in this study are being examined in an effort to better understand the relationship between char structure and heat treatment conditions. Results of this work will be available shortly.

• Research Organization: Pennsylvania State Univ., University Park
• OSTI ID: 6690907
• Report Number(s): CONF-820304-Vol.2
• Conference Information: Journal Name: Prepr. Pap. - Am. Chem. Soc., Div. Fuel Chem.; (United States) Journal Volume: 27:1
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404 -- Coal
Lignite
& Peat-- Gasification
010406* -- Coal & Coal Products-- Pyrolysis & Cracking-- (-1987)
CARBONACEOUS MATERIALS
CHARS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COAL
COAL GASIFICATION
DECOMPOSITION
DEVOLATILIZATION
ENERGY SOURCES
FOSSIL FUELS
FUELS
GASIFICATION
HEAT TREATMENTS
KINETICS
MATERIALS
OXIDATION
PYROLYSIS
PYROLYSIS PRODUCTS
REACTION KINETICS
THERMOCHEMICAL PROCESSES