APPLICATION OF CFD MODELING TOOLS TO OPTIMIZE 660 MW ULTRA SUPERCRITICAL CFB DESIGN

摘要

In addressing the need for reducing the cost of electricity and environmental footprint while maintaining the flexibility and reliability, a large-sized circulating fluidized bed (CFB) boiler designed with ultra-supercritical (USC) steam conditions has been developed by Alstom.It is a promising solution to burn efficiently low-grade fuels and to optimize fuel supply chain.Alstom has demonstrated its capability to design and supply efficient and reliable CFB boilers based on its own technology developed over the last 30 years.Alstom has recently announced the 660MW ultra supercritical CFB product rated at 660 MW for lignite B.The development process includes years of commercial scale design and technology improvements proven in the field needed to achieve this product milestone.While the design utilizes fundamentals that are well-known to the power industry, several novel features and design parameters of this new design have been studied with computer simulation.This paper describes several areas of the CFB boiler where Computational Fluid Dynamics (CFD) simulations were applied, with primary focus on the solids circulation patterns within the combustor zone and its implication on key parameters such as heat transfer and heat flux.Other areas of simulation such as the cyclone and backpass ductwork are also included.