WASTE HEAT RECOVERY STEAM GENERATOR

• Main Author: NAKAO MOTOROKU
• Format: Patent
• Language: English
• Published: 26.04.2002
• Edition: 7
• Subjects: BLASTING; HEATING; LIGHTING; MECHANICAL ENGINEERING; METHODS OF STEAM GENERATION; STEAM BOILERS; STEAM GENERATION; WEAPONS

PROBLEM TO BE SOLVED: To provide a structure for effectively preventing various low temperature corrosions from an inner surface of a casing expansion joint of a waste heat recovery steam generator. SOLUTION: High temperature gas from a gas turbine 1 is introduced into a casing 13 of a waste heat recovery steam generator to heat a steam generating exchanger (superheater 8, vaporizer 7, and an economizer 6, etc.), for production of steam, a thermal deformation absorbing expansion joint 12 is provided in the casing 13 t at least one position, and the inside of the expansion joint 12 is brought into contact with the high temperature gas flowing through the inside of the casing 13 the to heat the expansion joint 12 for prevention of low temperature corrosion of the expansion joint 12. When the expansion joint 12 is a structure protruded in a protrusion to the side of the waste gas flow passage in the casing 13, it is heated at all times with the high temperature gas in the casing, so that low temperature corrosion is effectively prevented, while when the expansion joint 12 is a structure protruded in protruded configuration to the side of the atmosphere outside the casing 13, a bypass passage 12 is connected for introducing the high temperature gas flowing through the interior of the casing in the protruded configuration portion and is heated.