Thermodynamic properties and phase relations for refractory-slag reactions in slagging coal gasifiers

Technical Report · Tue Dec 01 04:00:00 EST 1987

OSTI ID:5468792

Muan, A

The objective of the present research was to provide the data-base and understanding of the chemical parameters needed for prediction and evaluation of the performance of refractory materials under the conditions prevailing in slagging gasifiers. Testing of refractories under atmospheric conditions closely resembling those of slagging coal gasifiers has established that chromium oxide-containing refractories show particular promise in high-temperature gasification because of their high resistance to slagging attack. Consequently, the high-temperature behavior of chromium in crystalline and liquid oxide/silicate systems has been a main focus of this research project. In addition, studies of other high-temperature materials, mainly ZrO/sub 2/ in various combinations with other oxide components (e.g., CaO, MgO, Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 3/, TiO/sub 2/), have been carried out in order to ascertain the potential and chemical constraints of such materials. The main emphasis in this research has been on equilibrium aspects of high-temperature reactions, supplemented with a relatively small amount of work on kinetic aspects of such reactions. The equilibrium studies may be conveniently divided into two groups, viz., investigations of phase relations in multicomponent refractory-slag model systems, and investigations of thermodynamic properties (activity-composition relations) of individual phases. The main focus of the thermodynamic studies was the determination and interpretation of activity-composition relations of chromium oxide and Al/sub 2/O/sub 3/ in silicate melts of interest in slagging coal gasifiers. This was accomplished mainly by studying the equilibrium between chromium oxide in silicate melts and chromium metal in Pt-Cr alloys in a gas phase of known oxygen pressure. 15 refs., 52 figs.

• Research Organization: Pennsylvania State Univ., University Park (USA). Coll. of Earth and Mineral Sciences
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5468792
• Report Number(s): ORNL/Sub-80-09006/01; ON: DE88006034
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404* -- Coal
Lignite
& Peat-- Gasification
36 MATERIALS SCIENCE
360202 -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360205 -- Ceramics
Cermets
& Refractories-- Corrosion & Erosion
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CHALCOGENIDES
CHEMICAL ANALYSIS
CHEMICAL REACTIONS
CHROMIUM COMPOUNDS
CHROMIUM OXIDES
COAL GASIFICATION
COAL GASIFICATION PLANTS
COHERENT SCATTERING
CORROSION
CORROSION RESISTANCE
CORROSIVE EFFECTS
DIAGRAMS
DIFFRACTION
ELECTRON MICROPROBE ANALYSIS
GASIFICATION
INDUSTRIAL PLANTS
MATERIALS TESTING
MICROANALYSIS
MICROSCOPY
OPTICAL MICROSCOPY
OXIDES
OXYGEN COMPOUNDS
PHASE DIAGRAMS
PHASE STUDIES
PHYSICAL PROPERTIES
REFRACTORIES
SCATTERING
SILICON COMPOUNDS
SILICON OXIDES
SLAGS
TESTING
THERMOCHEMICAL PROCESSES
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
X-RAY DIFFRACTION
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES