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US2180148A
|
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Aerating tank
|
|
US1887490A
|
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Method of and apparatus for the treatment of sludge, sewage, and the like
|
|
US1914829A
|
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Household filter
|
|
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|
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Sewage purification
|
|
US1919331A
|
|
Household filter
|
|
US1820976A
|
|
Sewage treatment
|
|
US1820978A
|
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Digestion of coarse substances left on sewage screens in the sewage treatment
|
|
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|
|
Complete sewage treatment plant with submerged contact aerators
|
|
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|
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Subdivided activated sludge system for sewage treatment
|
|
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|
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Oscillating aerating pipe
|
|
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Means for unoiling sewage or sludge
|
|
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Aeration tank with submerged contact aerators
|
|
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Heatable sludge-digestion chamber for sewage treatment
|
|
GB255833A
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Improvements in the treatment of sewage with removal of colloidal matter therefrom
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Aerated contact filter for sewage treatment
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Aeration tank for sewage treatment by activated sludge
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GB256489A
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Improved sewage treatment by activated sludge
|
|
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Fishpond with sewage supply
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Apparatus for sewage treatment by activated sludge in combination with sludge digestion
|
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Method of and apparatus for dealing with floating sludge in digestion chambers for sewage treatment
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