Pyrohydrolysis system for processing fluorine-containing spent and waste materials

Patent · Tue Jun 19 04:00:00 EDT 1979

OSTI ID:5712974

Andersen, J N; Bell, N

A pyrohydrolysis system is provided for the recovery of valuable components from waste and spent materials generated in electrolytic aluminum reduction facilities. The pyrohydrolysis system employs a dense phase fluidized bed reaction zone for the pyrohydrolysis of coarse feed, a dilute phase fluidized reaction zone for pyrohydrolyzing fine feed, this zone being superimposed and interconnected with the dense phase zone. The offgases, after removal of the solids, are contacted in a dilute phase fluidized zone, with a source of Al/sub 2/O/sub 3/ to remove residual Na values and to produce Na-free HF. The solids from the first dilute zone, having a desired high Na:Al atom ratio, can be combined with the product clinker from the dense bed zone. The offgas, containing the source of Al/sub 2/O/sub 3/ is subjected to solids separation, the solids-free and Na-free UF is utilized, while the solids of low Na:Al mole ratio are recycled to the residual Na conversion step.

• Assignee: Kaiser Aluminum and Chemical Corp.
• Patent Number(s): US 4158701
• OSTI ID: 5712974
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320305* -- Energy Conservation
Consumption
& Utilization-- Industrial & Agricultural Processes-- Industrial Waste Management
ALKALI METALS
ALUMINIUM
CHEMICAL REACTIONS
DECOMPOSITION
ELEMENTS
FLUORINE
HALOGENS
HYDROLYSIS
INDUSTRY
LYSIS
MANAGEMENT
MATERIALS RECOVERY
METAL INDUSTRY
METALS
NONMETALS
PROCESSING
PRODUCTION
PYROLYSIS
RECOVERY
SODIUM
SOLVOLYSIS
THERMOCHEMICAL PROCESSES
WASTE MANAGEMENT
WASTE PROCESSING