Type of Document Master's Thesis Author Gentile, Maria URN etd-11142012-040215 Title Alkali attack of coal gasifier refractrry [sic] lining Degree Master of Science Department Materials Engineering Advisory Committee
Advisor Name Title Brown, Jesse J. Jr. Committee Chair Farkas, Diana Committee Member Yoon, Roe-Hoan Committee Member Keywords
- Refractory materials
Date of Defense 1987-05-15 Availability restricted Abstract
An experimental test system was designed to simulate the operating conditions found in nonslagging coal gasifiers. The reaction products that form when refractory linings in coal gasifiers are exposed to alkali impurities (sodium or potassium) were experimentally determined. Analysis of selected physical and chemical properties of the reaction products, which typically form between the alkali and the refractory will lead to a better understanding of the mechanisms behind refractory failures associated with alkali attack.
The reaction products sodium aluminate (Na2O•Al203), N2C3A5 (2Na20·3CaO·5Al203), nepheline (Na20•Al203•2SiO2), potassium aluminate, (K2O•Al203), and kaliophilite (K2O•Al203•2Si02) were synthesized and their solubility in water and coefficients of linear thermal expansion were: measured. Of the compounds tested, the formation of potassium aluminate would be the most detrimental to the gasifier lining. The linear thermal expansion of potassium aluminate was 2.05% from room temperature to 800°C, which was twice as large as the other compounds. Potassium aluminate also possessed the highest solubility in water which was 8.893/L at 90°C.
Filename Size Approximate Download Time (Hours:Minutes:Seconds)
28.8 Modem 56K Modem ISDN (64 Kb) ISDN (128 Kb) Higher-speed Access LD5655.V855_1987.G467.pdf 1.55 Mb 00:07:10 00:03:41 00:03:13 00:01:36 00:00:08next to an author's name indicates that all files or directories associated with their ETD are accessible from the Virginia Tech campus network only.
If you have questions or technical problems, please Contact DLA.