1997 Volume 46 Issue 1 Pages 16-23
Laboratory corrosion tests were performed for investigating influence of ash composition on corrosion behavior of four candidate materials for the superheater of waste incineration plants. The synthetic ashes and deposits on actual boiler tubes were used in the tests. It was found that the corrosivity of the ash depended not only on the contents of metal oxides, like PbO and CuO, but also on the content of alkaline metal chlorides. Because Alloy 625 showed an excellent corrosion resistance in a molten chloride, alloying with Ni seemed to enhance corrosion reisistivity against the chloride melt. On the other hand, in a mixture of molten chloride and sulfate, the metal loss of Alloy 625 was almost equal with that of SUS 310 S and SUS 347 H. From this result, alloying with Cr seemed to relatively improve corrosion resistance in the mixture melt.
