Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4840736 | Process for producing combustible sewage sludge filter cakes in filter presses | Herbert Lauer, Manfred Neuwirth | 1989-06-20 |
| 4828715 | Cleaning and disposal of carbon black and ash containing wastewaters | Siegfried Marquardt, Gero Lueth, Robert K. Horn, Uwe Kempe | 1989-05-09 |