Pilot plant studies of the fluidized bed waste calcination process

Technical Report ·

OSTI ID:6604052

Buckham, J A; McBride, J A

Studies were conducted in 6- and 12-in, dia. electrically heated fluidized beds and in a 24-in.-square NaK-heated bed and are being extended in the two larger units. Although exploratory studies demonstrated the feasibility of this process for stainless steel and zirconium fuel wastes, the overwhelming majority of the work was with aluminium fuel wastes. Feed rates from 5 to 150 1/h per air-atomizing nozzle were used with no perceptible tendency toward caking; capacity of all units was limited by the rate of heat introduction through internal surfaces. Measured heat transfer coefficients range from 40 to 110 Btu/h-/sup 0/F-ft/sup 2/, depending upon bed particle size and fluidized bed density. Particle size was controlled by varying the atomizing air rate, the major factor governing particle attrition; quantitatively this effect is very dependent on the crystalline form of alumina produced. Various operating factors make significant differences in the rate of conversion of amorphous alumina calcine to the alpha, gamma, or iota form. Particle attrition increases with alpha alumina content; hence, average bed particle size decreases and particle elutriation rate increases with increasing alpha content. High alpha-content beds are more dense and contain less nitrate, both desirable features. Sodium is a necessary feed ingredient for alpha alumina formation; its effects can be overcome by addition of boric acid to the feed. Addition of one of these components to the feed is recommended to obtain the desired product form. Superficial fluidizing velocities from 0.5 to 2.5 fps were used; best results are obtained with velocities under 1.0 fps. Studies were made with and without condensing the off-gas stream and with near-total recycle of non-condensable off-gas for fluidization. The latter method of operation shows promise for minimizing atmospheric contamination.

• Research Organization: Phillips Petroleum Co., Idaho Falls, ID (USA)
• OSTI ID: 6604052
• Report Number(s): TID-17177
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
RADIOACTIVE WASTE PROCESSING
PILOT PLANTS
SOLIDIFICATION
ALUMINIUM
ALUMINIUM OXIDES
BORIC ACID
CALCINATION
FLUIDIZED BED
NITRATES
NOZZLES
PARTICLE SIZE
PERFORMANCE TESTING
ALUMINIUM COMPOUNDS
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
ELEMENTS
FUNCTIONAL MODELS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
MANAGEMENT
METALS
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PROCESSING
PYROLYSIS
SIZE
TESTING
THERMOCHEMICAL PROCESSES
WASTE MANAGEMENT
WASTE PROCESSING
052001* - Nuclear Fuels- Waste Processing