Improved materials for coal-fired boiler superheater and reheater tubes subjected to fireside corrosion

Conference · · TMS (The Metallurgical Society) Paper Selection; (USA)

OSTI ID:5323925

Rehn, I M ^[1]

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1. Foster Wheeler Development Corp., Livingston, NH (USA)

A laboratory test program (funded by EPRI and FWDC) was conducted to develop improved corrosion resistant alloys for superheater and reheater tubes in direct coal-fired steam generators - operating at higher temperatures than currently in use. The program consisted of a broad literature review and laboratory evaluation of 19 commercial and semicommercial alloys, 19 custom-melted alloys and 18 types of high-temperature coatings which were subjected to flowing flue gas and molten alkali-iron trisulfate ash at 675 and 790 C. Almost all commercial and semicommercial alloys suffered severe attack and pitting under the laboratory fireside test environment at 675 C. Several experimental alloys showing promise of substantial improvement in corrosion resistance were evaluated for potential applications as a cladding or as a high alloy, wrought tube. The best performing austenitic alloys - containing aluminum, silicon, and manganese additions - generated an adherent scale which retarded fireside attack 6 to 10 times better than commercial Type 304 stainless steel, which suffered loss of scale and provided minimal protection from the molten trisulfate attack.

• OSTI ID: 5323925
• Report Number(s): CONF-840909-; CODEN: TMPSA
• Journal Information: TMS (The Metallurgical Society) Paper Selection; (USA), Vol. 56; Conference: TMS-AIME fall meeting, Detroit, MI (USA), 16-20 Sep 1984; ISSN 0197-1689
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
36 MATERIALS SCIENCE
AUSTENITIC STEELS
CORROSION RESISTANCE
STEAM GENERATORS
SUPERHEATERS
CORROSION RESISTANT ALLOYS
ALLOYS
ALUMINIUM ADDITIONS
ASHES
BENCH-SCALE EXPERIMENTS
COAL
COMBUSTION
COMPARATIVE EVALUATIONS
CORROSIVE EFFECTS
FLUE GAS
IRON SULFATES
MANGANESE ADDITIONS
MOLTEN SALTS
PITTING CORROSION
SILICON ADDITIONS
STAINLESS STEEL-304
TEMPERATURE DEPENDENCE
ALUMINIUM ALLOYS
BOILERS
CARBONACEOUS MATERIALS
CHEMICAL REACTIONS
CHROMIUM ALLOYS
CHROMIUM-NICKEL STEELS
CORROSION
ENERGY SOURCES
FOSSIL FUELS
FUELS
GASEOUS WASTES
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
HIGH ALLOY STEELS
IRON ALLOYS
IRON BASE ALLOYS
IRON COMPOUNDS
MANGANESE ALLOYS
MATERIALS
NICKEL ALLOYS
OXIDATION
OXYGEN COMPOUNDS
RESIDUES
SALTS
SILICON ALLOYS
STAINLESS STEELS
STEEL-CR19NI10
STEELS
SULFATES
SULFUR COMPOUNDS
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENT COMPOUNDS
VAPOR GENERATORS
WASTES
014000* - Coal
Lignite
& Peat- Combustion
360105 - Metals & Alloys- Corrosion & Erosion