Lee J.C.,Babcock Power |
Coyle M.,DB Riley, Inc.
American Society of Mechanical Engineers, Power Division (Publication) POWER | Year: 2014
With availability of natural gas at competitive prices and increased scrutiny of coal-fired generation, conversion of coal-fired units to natural gas-firing is a popular option to consider as an alternative to capital-intense environmental equipment upgrades or even retirement. Many owners are considering this option as a way to keep an existing plant open while meeting new and pending environmental regulations. There are many technical challenges associated with such a conversion and the owner should consider them all carefully on a case-by-case basis. This paper will present an overview of these challenges, with a focus on the steam generator and what an owner/operator needs to understand when considering conversion to natural gas-firing. Typical effects of a conversion to natural gas-firing for a utility-scale coal-fired steam generator are discussed along with potential operational effects of such a project. A general discussion of differences in furnace and convective pass performance characteristics for the different fuels is presented along with a discussion of how these differences can translate to technical challenges in a conversion project. Typical effects on boiler efficiency and emissions as well as the most commonly required modifications are reviewed. Finally, a comprehensive review of the operational affects of the converted unit is presented. Copyright © 2014 by ASME. Source
DB Riley, Inc. | Date: 2013-05-02
A trunnion seal assembly for joining a stationary inlet/outlet box of a ball tube mill to a rotational interior of the ball tube mill includes an outer ring component configured to be mounted to an outer wall of the stationary inlet/outlet box. An inner ring component is joined to the outer ring component substantially concentrically with the outer ring component. A flexible pad seal is configured to be joined to the outer wall of the stationary inlet/outlet box proximate outer ring component. The pad seal includes a first annular sealing surface. A mill head extension ring configured to be joined to a rotational mill head is located proximate to and substantially concentric with the inner ring component. The mill head extension includes a second annular sealing surface sealingly engaged with the first annular sealing surface of the flexible pad seal.
DB Riley, Inc. | Date: 2012-02-13
DB Riley, Inc. | Date: 2013-02-14
Wheelabrator Technologies Inc. and DB Riley, Inc. | Date: 2011-08-08
A steam generator includes a furnace configured and adapted to generate a stream of furnace exit gases from the combustion of municipal solid waste fuel. At least one superheater is disposed within an upper portion of the furnace or backpass. The superheater is configured and adapted to superheat fluids within the superheater by facilitating heat transfer between fluids within the superheater and furnace exit gases outside the superheater. At least one waterwall furnace platen is disposed within the furnace upstream from the superheater, the waterwall furnace platen is configured and adapted to lower furnace exit gas temperature at the superheater by facilitating heat transfer between fluids within the waterwall furnace platen and furnace exit gases outside the waterwall furnace platen.