Once-through steam generator

• Main Authors: Taylor Darryl, Stark Daniel, Thompson Anthony A, Pasha Akber, Flannery Kelly M
• Format: Patent
• Language: English
• Published: 16.01.2018
• Subjects: AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHINBOILERS; BLASTING; CONTROLLING WATER LEVEL; FEED-WATER SUPPLY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HEATING; LIGHTING; MECHANICAL ENGINEERING; METHODS OF STEAM GENERATION; PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER; STEAM BOILERS; STEAM GENERATION; SUPERHEATING OF STEAM; TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; WEAPONS

A once-through steam generator comprises a duct having an inlet end in communication with a source of a hot gas; and a tube bundle installed in the duct and comprising multiple heat transfer tubes. The tube bundle has an economizer section, an evaporator section, and a superheater section. A steam separating device may be positioned between the evaporator section and the superheater section, wherein, as part of a wet start-up, hot water collected by the steam separating device is delivered from the steam separating device to mix with cold feedwater before it is introduced into the economizer section. A start-up module may be positioned in the duct near the inlet end, wherein, as part of a dry start-up, cold feedwater is delivered into the start-up module to generate hot water that is then mixed into the feedwater stream before it is introduced into the economizer section.