June 2009 marked the initial coal-fired operation of the world's first supercritical pulverized coal-fired low mass flux vertical tube Benson boiler. Jinzhushan 3, located in Hunan Province in the People's Republic of China, is a 600 MW B&W PGG VTUP™ once-through boiler with vertical tube furnace construction designed to burn Chinese anthracite using downshot pulverized coal technology. The boiler was supplied by Babcock & Wilcox Beijing Company, Ltd. (BWBC) under license from B&W PGG. This paper reviews the development history of supercritical, once-through steam generator technology and product advancements. Downshot pulverized coal combustion technology is used to efficiently utilize low volatile anthracite coal that is difficult to burn conventionally. The unique design features of the downshot combustion system are reviewed as well as the adaptation of this technology to the VTUP design. Both the SWUP and VTUP boiler designs can be supplied to meet the market requirements of today’s supercritical pulverized coal applications. The SWUP boiler represents a well-proven solution that provides consistent heat dis¬tribution to all tubes flowing through the furnace circuits making it insensitive to the natural variations that occur in furnace heat flux patterns that result from variations in fuel characteristics and types burned, boiler cleanliness conditions, air staging for combustion NOx control, and changes in pulverizer operating conditions. The VTUP boiler offers a solution that takes advantage of the benefits of natural circulation where tubes exposed to surges in heat flux will draw more flow to cool the tube instead of reducing flow due to higher resistance. The successful operation of Jinzhushan 3 demonstrates that this process works as expected and offers an alternative that has advantages of simpler construction, a less complicated wall support system, and lower furnace pressure drop contributing to more efficient net plant electric generation. Both the SWUP and VTUP furnace designs represent good alternative technologies for supercritical boiler applications that can be used to meet the needs of the modern power plant. The full paper can be downloaded from the B &W site as BR#1849 Successful Operation of Jinzhushan 3, the World's First PC-Fired Low Mass Flux Vertical Tube Supercritical Boiler

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• Babcock & Wilcox Power Generation Group

• Anthracite

• Ultrasupercritical

• Vertical Tube Boiler

• Air Staging

• China

• Article