Diffusion Coatings for Corrosion-Resistant Components in Coal Gasification Systems

Technical Report · Tue Mar 15 04:00:00 EST 2005

DOI:https://doi.org/10.2172/891454· OSTI ID:891454

Krishnan, Gopala N ^[1]; Malhotra, Ripudaman; Alvarez, Esperanza; Lau, Kai-Hung; Perez-Mariano, Jordi; Sanjurjo, Angel

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1. Sri International

Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high-temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low-cost alloy may improve its resistance to such sulfidation attack, and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. During this period, we conducted two 300-hour tests. In the first test, we exposed samples at 900 C under conditions simulating the high-temperature heat recovery unit (HTHRU). The second test was at 370 C, corresponding to the filter units following the HTHRU. The tests were showed the resilience of silicon nitride as a coating component, and the new coating procedures better penetrated the pores in sintered metal filter samples. Finally, we also received samples that were exposed in the Wabash River plant. Unfortunately, all these samples, that were prepared last year, were severely eroded and/or corroded.

• Research Organization: Sri International
• Sponsoring Organization: USDOE
• DOE Contract Number: FC26-03NT41616
• OSTI ID: 891454
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
36 MATERIALS SCIENCE
ALLOYS
COAL GAS
COAL GASIFICATION
COATINGS
COMBINED CYCLES
DEPOSITION
DIFFUSION COATINGS
HEAT EXCHANGERS
HEAT RECOVERY
OPERATING COST
PERFORMANCE
SILICON NITRIDES
STAINLESS STEELS
SULFIDATION
TURBINES