Measurements of the corrosion of two ods alloys by flowing coal slag

摘要

The High-Performance Power System, or HiPPS, Program was started by the U.S. Department of Energy to encourage the development of a coal-fired power system that would employ an indirectly fired combined-cycle that is one-third more efficient than existing power plants while producing only one-tenth of the emissions. One concept for a HiPPS plant proposed by the United Technologies Research Center employed a very-high-temperature heat exchanger composed of oxide dispersion-strengthened (ODS) alloys that would have to withstand corrosion by flowing coal slag. The University of North Dakota Energy & Environmental Research Center was a major subcontractor on that project, building and operating both pilot- and bench-scale systems for testing the heat exchanger and other subsytems key to the operation of such a plant. In this paper, we present the results of corrosion tests of two ODS alloys cooled to 1000°, 1100°, and 1200 °C while exposed to flowing coal slag at 1500 °C. The alloys are MA754, a nickel-based chromia former, and MA956, an iron-chromium alumina former. The tests were performed in a bench-scale system in air for 100 hours each.