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US2477815A
|
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Process and apparatus for purifying wastes
|
|
US2457057A
|
|
Waste purification process and apparatus
|
|
US2438342A
|
|
Waste liquor aerator
|
|
US2430519A
|
|
Regenerative digester
|
|
US2413838A
|
|
Waste purification apparatus having superposed aerating and clarifying chambers
|
|
US2204093A
|
|
Mechanical aerator
|
|
US2223258A
|
|
Sewage purification apparatus
|
|
US2223257A
|
|
Sewage treating apparatus
|
|
US2154132A
|
|
Process of controlling the purification of sewage
|
|
US2227099A
|
|
Method for settling and filtering sewage liquors
|
|
US2138349A
|
|
Method and apparatus for aerating sewage
|
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CA150178A
|
|
Cartridge fuse
|
|
CA143612A
|
|
Refillable cartridge fuse
|
|
CA141887A
|
|
Cartridge fuse
|
|
US1005253A
|
|
Refillable cartridge-fuse.
|
|
US994413A
|
|
Refillable cartridge-fuse.
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