|
US2246224A
|
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Disposal of garbage or garbage and sewage sludge and the like
|
|
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|
|
Activated sludge purification of sewage and other liquids
|
|
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|
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Filter
|
|
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Apparatus for and method of treating sewage sludge and the like
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Filter
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Method of making screen plates
|
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Filter
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Method of filtering sewage and the like
|
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Press
|
|
US1999058A
|
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Activated sludge sewage treatment
|
|
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Automatic screening and filtering apparatus
|
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Rotary brush
|
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CA383110A
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Sewage screening dewatering apparatus
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CA355836A
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Screening and filtering apparatus
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