Behavior of coal slag during gasification

Journal Article · Thu Dec 01 04:00:00 EST 1983 · Am. Ceram. Soc. Bull.; (United States)

OSTI ID:7089224

Bakker, W T; Coons, W C; Darling, S L

This paper is based on the operating experience of an atmospheric pressure, two-stage, entrained flow, air-blown slagging gasifier. The paper briefly describes the design and operation of the gasifier, coal slag mineralogy, and the changes in slag mineralogy encountered during operation due to refractory wear and the reducing atmosphere within the gasifier. The wear rates of different kinds of refractory used in the gasifier are also briefly described. Coal slags, which depend mainly on a high iron oxide content to provide a high slag fluidity during gasification, are quite sensitive to changes in oxygen partial pressure and dissolution of refractory in the slag. Both the removal of FeO and metallic iron and the addition of Al/sub 2/O/sub 3/ and Cr/sub 2/O/sub 3/ result in the precipitation of large volumes of crystallites, which can adversely affect slag viscosity. Concerning refractory wear rates, the burned Al/sub 2/O/sub 3/-Cr/sub 2/O/sub 3/ brick in the high temperature slagging zones showed lower wear rates than unfired monolithic materials of the same general composition. However, thick refractory lining designs using either type showed excessive wear rates in the combustor. The thin refractory studded lining was the only design found acceptable here, and showed good durability on the test panel in the combustor through over 5000 hours of operation. In the lower temperature slagging zones such as the diffuser, burned Al/sub 2/O/sub 3/-Cr/sub 2/O/sub 3/ brick may be acceptable, but rammed unfired refractories are not. For the nonslagging zones, a 90% alumina ramming mix gave satisfactory results.

• Research Organization: Electric Power Research Inst., Palo Alto, CA
• OSTI ID: 7089224
• Journal Information: Am. Ceram. Soc. Bull.; (United States), Journal Name: Am. Ceram. Soc. Bull.; (United States) Vol. 62:12; ISSN ACSBA
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010400 -- Coal
Lignite
& Peat-- Processing
010800* -- Coal
Lignite
& Peat-- Waste Management
BRICKS
BUILDING MATERIALS
CARBONACEOUS MATERIALS
CHEMICAL COMPOSITION
CHEMICAL REACTORS
COAL
COAL GASIFICATION
COMBUSTION CHAMBERS
COMPARATIVE EVALUATIONS
DESIGN
ENERGY SOURCES
FOSSIL FUELS
FUELS
GASIFICATION
MATERIALS
MECHANICAL PROPERTIES
MINERALOGY
OPERATION
REFRACTORIES
SLAGS
THERMOCHEMICAL PROCESSES
WEAR RESISTANCE