IP Library › Granted Patent US 4,253,949
Granted Patent Utility
US 4,253,949 · App. 05/671,543

Sewage treatment-flotation apparatus

Inventors: David A. Hines, Richard Thomas Jones, Frank C. Roesler, deceased
Patented Case View Patent ↗
Granted: Mar 3, 1981 Filed: Mar 29, 1976
Inventors
David A. Hines
Richard Thomas Jones
Frank C. Roesler, deceased
Assignee (at issue)
IMPERIAL CHEMICAL INDUSTRIES LIMITED

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Quick Facts
Patent No.
US 4,253,949
App. No.
05/671,543
Filed
1976-03-29
Granted
1981-03-03
Kind
A