Division 4 Waste
United Kingdom
| Technique | Description | Applicability | |
|---|---|---|---|
| (a) | Conditioning | Chemical conditioning (i.e. adding coagulants and/or flocculants) or thermal conditioning (i.e. heating) to improve the conditions during sludge thickening/dewatering. | Not applicable to inorganic sludges. The necessity for conditioning depends on the sludge properties and on the thickening/dewatering equipment used. |
| (b) | Thickening/dewatering | Thickening can be carried out by sedimentation, centrifugation, flotation, gravity belts, or rotary drums. Dewatering can be carried out by belt filter presses or plate filter presses. | Generally applicable. |
| (c) | Stabilisation | Sludge stabilisation includes chemical treatment, thermal treatment, aerobic digestion, or anaerobic digestion. | Not applicable to inorganic sludges. Not applicable for short-term handling before final treatment. |
| (d) | Drying | Sludge is dried by direct or indirect contact with a heat source. | Not applicable to cases where waste heat is not available or cannot be used. |