The value proposition of circulating fluidized-bed technology for the utility power sector
R Giglio, N.J. Castilla
Circulating fluidized-bed (CFB) combustion technology has been around
for over 40 years, but over the last 6 years it has been commercially
demonstrated at the 500 MWe scale at the Lagisza plant located in Bedzin,
Poland. The CFB at the Lagisza plant has unique first-of-a-kind design
features, such as vertical-tube supercritical steam technology and a lowtemperature
flue-gas heat extraction that allows the plant to achieve high
plant efficiencies of over 43% (net lower heating value). Another unusual
feature for a coal power plant is that this plant meets all its atmospheric
emission permit levels without any post-combustion de-NOx or de-SOx
equipment such as selective catalytic reduction (SCR) or flue-gas
desulphurization (FGD).
CFB clean coal power technology is entering the utility power sector
just in time to help deal with declining quality in internationally traded
coals and to promote the large-scale use of economic, low-quality domestic
fuels. Owing to the very attractive price discounts, growing supplies of
low-quality Indonesian coals are outpacing the supply of high-quality
Australian, Russian, and US coals. In Germany and Turkey, the use of
domestic lignites for power production provides a secure and economic
energy solution while creating domestic jobs.
Conventional pulverized coal (PC) boilers will have trouble accepting
these off-specification coals because of their narrow fuel specifications;
they typically call for heating values above 5500 kcal/kg. This limitation is
not an issue for CFB technology because of its ability to burn the worst
and best of coals with heating values ranging from 3900 to 8000 kcal/kg.
This paper provides an outlook for future coal supply, quality, and
price, as well as a review of the technical and economic benefits of CFB
technology firing low-quality fuels for utility power generation.
Keywords: value proposition, CFB, flexibility, lignite, Lagisza, circulating fluidizedbed,
power generation.