Issued Patents All Time
Showing 1–7 of 7 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6673240 | Feed control system for liquid clarification tanks | Donald N. Ruehrwein | 2004-01-06 |
| 6171498 | Upflow water clarifier with central pier | Daniel H. Phillips, David K. Wyness | 2001-01-09 |
| D424156 | Industrial or municipal water clarifier | Daniel H. Phillips, Deanna F. Young | 2000-05-02 |
| 5958249 | Method and apparatus for withdrawing effluent from a solids-contacting vessel | Donald N. Ruehrwein, Daniel H. Phillips | 1999-09-28 |
| 5942116 | Anaerobic sludge digester | Sidney E. Clark, John R. Currie | 1999-08-24 |
| 5716519 | Apparatus for discharging fluid additives into a water treatment vessel | James M. Schleife, Donald N. Ruehrwein | 1998-02-10 |
| 5695648 | Method and apparatus for withdrawing effluent from a solids-contacting vessel having an adjustable weir | Donald N. Ruehrwein, Daniel H. Phillips | 1997-12-09 |