Effects of alternate fuels report No. 7: analysis of failure of a mullite-based refractory brick in an industrial oil-fired burner
Industrial conversion from natural gas to alternate fuels, such as residual oils and coal, often results in accelerated degradation of refractory materials due to chemical reactions with the metal impurities in the alternate fuels. The cause of failure of a refractory brick used in an industrial burner firing an alternate fuel is described. The burner, which was used to calcine CaSO/sub 4/ in a lime-type kiln, was fired with No. 6 residual oil. The refractory lining in the burner was constructed of aluminosilicate brick, castable, and mortar in contact with one another. The lining deteriorated after about 1000 h, during which the maximum hot-face temperature was about 1750/sup 0/C. The degraded refractories were subjected to chemical analyses, ceramography, x-ray diffraction, scanning electron microscopy, and electron microprobe analysis. Liquid phases that formed in the castable and mortar during operation of the burner at temperatures above about 1600/sup 0/C reacted with the brick, resulting in decomposition of mullite. Contamination of the original refractory with CaO and V/sub 2/O/sub 5/ resulted in the formation, during cooling, of compounds which are less refractory than the original castable and mortar. It was concluded that failure was initiated by melting in the castable and mortar. Large concentrations of aggressive oxide liquid were in the burner lining at the service temperature. The liquid phase eventually advanced into the refractory from the hot face to the extent that the brick grossly deteriorated. Therefore, rapid degradation of the refractory system was due to a combination of excess temperature and fluxing by process carry-over and impurities from the fuel oil.
- Research Organization:
- Oak Ridge National Lab., TN (USA)
- DOE Contract Number:
- W-7405-ENG-26
- OSTI ID:
- 6136189
- Report Number(s):
- ORNL/TM-6878
- Country of Publication:
- United States
- Language:
- English
Similar Records
Effects of alternate fuels refractory test facility (RTF) Test 2: evaluation of magnesia-based bricks and mortar and alumina-based bricks, castables, and fibrous insulations exposed to residual oil combustion products
Effects of alternate fuels refractory test facility test 3. Part 2. Analysis of magnesia- and alumina-based dense refractories exposed to the combustion products of No. 6 residual oil
Effects of alternate fuels report No. 8: analysis of degradiation of magnesia-based refractory bricks from a residual oil-fired rotary cement kiln
Technical Report
·
Fri Feb 29 23:00:00 EST 1980
·
OSTI ID:5582565
Effects of alternate fuels refractory test facility test 3. Part 2. Analysis of magnesia- and alumina-based dense refractories exposed to the combustion products of No. 6 residual oil
Technical Report
·
Tue Jul 01 00:00:00 EDT 1980
·
OSTI ID:5381980
Effects of alternate fuels report No. 8: analysis of degradiation of magnesia-based refractory bricks from a residual oil-fired rotary cement kiln
Technical Report
·
Thu May 01 00:00:00 EDT 1980
·
OSTI ID:5272639