Superheater corrosion in plants burning high-chlorine coals. Final report

Technical Report · Tue Dec 01 04:00:00 EST 1992

OSTI ID:10114575

Latham, E P; Chamberlain, J ^[1]

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1. National Power plc, Leatherhead (United Kingdom)

A programme to evaluate the fireside corrosion performance of candidate alloys for superheater/reheaters of advanced high efficiency coal fired power plants was established by EPRI. Corrosion probe trials were undertaken at a number of existing power stations in both the USA and UK burning a range of coal compositions. This report describes the performance of the candidate alloys from the corrosion probe trial at Drax Power station in the UK. The environment at Drax was considered to be fairly aggressive as high chlorine coals were burnt. Candidate materials were exposed on the probe for up to 10000h. These materials included alloys for use as monobloc tubing or as an outer layer of a co-extruded tube. Various coatings were also tested. The corrosion resistance of the alloys was dominated by their chromium content. The most resistant alloys being ln671, Cr35A and Alloy 4002. Alloys T310, HR3C, Cr30A and NF709 were susceptible to pitting attack. Poor corrosion resistance was demonstrated by the alloys El250 and T91 with general surface attack around the whole of the fireside front being observed. Of the coatings tested the plasma sprayed 50%Cr/50%Ni coating was the most promising for long term protection. Severe pitting was observed on the chromised coatings.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (United States); National Power plc, Leatherhead (United Kingdom)
• Sponsoring Organization: Electric Power Research Inst., Palo Alto, CA (United States)
• OSTI ID: 10114575
• Report Number(s): EPRI-TR--101729; ON: UN93005249
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
200104
36 MATERIALS SCIENCE
360105
CHLORINE
COAL
COATINGS
COMBUSTION PRODUCTS
COMPONENTS
CORROSION
CORROSION AND EROSION
CORROSION RESISTANCE
CORROSIVE EFFECTS
EXPERIMENTAL DATA
FOSSIL-FUEL POWER PLANTS
INCONEL 671
IRON SULFATES
MATERIALS TESTING
PITTING CORROSION
PROBES
STAINLESS STEELS
SUPERHEATERS
UNITED KINGDOM