 |
| |||
| percolating filter | |||
| trickling filter | |||
| trickling filter (Tropfkörperreaktor/ Rieselfilmreaktor) | |||
| biofilter | |||
| bacterial bed; biological filter | |||
| contact aerator | |||
| percolation filter; sprinkling filter | |||
| |||
| plastic filled trickling filter | |||
| Tropfkörper: 12 phrases in 3 subjects |
| Construction | 2 |
| Environment | 5 |
| Natural resourses and wildlife conservation | 5 |