Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

The development of new analysis methods to predict agglomeration and deposition in FBCs

Technical Report ·
OSTI ID:83315
; ;  [1]
  1. Univ. of North Dakota, Grand Forks, ND (United States); and others
New methods for determining the chemical, mineralogical, and physical characteristics of bed particles and agglomerates produced in fluidized-bed combustion (FBC) systems are described. The methods utilized an automated digital electron microscope to determine the size distribution, shape, and quantitative mineralogy of bed particle cores and the chemical composition and proportion of their corresponding ash coatings. Application of the methods to ash-coated sand grains and agglomerates produced from the bench-scale FBC of three Beulah North Dakota lignites indicated that ash deposition was unaffected by the chemical or mineralogical composition of the original bed. The degree of ash coating was primarily related to the Na{sub 2}O content of the coals. Agglomerate neck growths and their corresponding ash coatings were compositionally indistinguishable, suggesting a lack of chemical reaction between cohering bed particles. Physical processes involving the collisions of bed particles with molten-ash-coated char particles, vaporization/condensation mechanisms, and random collisions between ash-coated bed particles are invoked to explain ash deposition and agglomeration.
Research Organization:
Electric Power Research Inst., Palo Alto, CA (United States); Reaction Engineering International, Salt Lake City, UT (United States)
OSTI ID:
83315
Report Number(s):
EPRI-TR--104982; CONF-9408200--
Country of Publication:
United States
Language:
English