摘要 |
Regenerated adsorbent particles, such as activated carbon, are recovered from a wet oxidation-regenerated mixed sludge liquor from a wastewater treatment system by diluting and settling a blowdown slurry (20) from the wet oxidation reactor (12) to obtain a first aqueous phase (32) containing primarily regenerated adsorbent particles and fine ash particles and a first solids phase (28) containing primarily grit particles. The first aqueous phase (32) is combined with a portion (16) of the regenerated adsorbent particle slurry withdrawn from the upper portion of the wet oxidation reactor (12) and, after treatment with a dispersing agent (36) and then an anionic flocculating agent (44), the resulting mixture (46) is settled to obtain a second aqueous phase (54) containing primarily fine ash particles and a second solids phase (50) containing primarily regenerated adsorbent particles. The second solids phase (50) is recycled to the wastewater treatment system for re-use and, after treatment with a cationic flocculating agent (58), the second aqueous phase (54) is settled to obtain a substantially particle-free third aqueous phase (66) and a third solids phase (64) containing primarily fine ash particles. Slurries (28) and (64) containing the grit and fine ash particles are combined and dewatered prior to disposal. |