Kraft recovery boiler, and methods for restoring and mounting a recovery boiler and to mount a kraft black liquor gasifier

摘要

Kraft recovery boiler, and.Methods for restoring and mounting a recovery boiler and to mount a kraft black liquor gasifier alloy austenitic Ni Cr Fe is provided as a material of the outer tube (12) for improved resistance to crack and corrosion of tubes composite (10) used to co The lower section of nstruir Kraft recovery boiler furnaces (20).The alloy is essentially based on percentage by weight, 25 to 35, Cr, 5 to 15 Fe and 50 to 70, Ni, with the other side connection elements and impurities such as they would normally be present in commercial alloys. This range of composition includes, as a preferred composition, the range corresponding to the commercial Alloy 690 (a n06690).