Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4833185 | Sludge obtained when processing waste lubricating oil, and a method for utilizing the sludge | — | 1989-05-23 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4833185 | Sludge obtained when processing waste lubricating oil, and a method for utilizing the sludge | — | 1989-05-23 |