| 210 / | HD | LIQUID PURIFICATION OR SEPARATION |
| 600 | DF | PROCESSES {14} |
| 702 | DF | .~ Making an insoluble substance or accreting suspended constituents {14} |
| 703 | DF | .~.~ Effecting flotation {1} |
| 704 | DF | .~.~.~ Including chemical addition (with or without bouyancy gas) {1} |
| 705 | | .~.~.~.~ Chemically specified precipitant, coagulant, or flocculant {1} |
| 706 | DF | .~.~.~.~.~> And significant characteristic of the bouyancy gas, other than mere addition of same {1} |