| 摘要 |
<p>The invention concerns a method for thickening sludge derived from a water treatment plant by flocculation-decantation with floc ballasted with micro- sand or other dense granular material using a liquid cyclone treatment (1) o f the decantation sludge. The invention is characterised in that it comprises successive steps which consist in: degassing (3) the overflow sludge of the liquid cyclone treatment (1) from the ballasted flocculation-decantation uni t, said degassing step being carried out on a corresponding degassing surface a t a degassing surface velocity of less than 100 mph; injecting at least a flocculating reagent (4) into said sludge; and thickening said sludge in at least a laminar sludge thickener (6), with a stilling floor load calculated at the thickener floor surface higher than 200 kg of suspended matter per m2 pe r day and the extracted sludge concentration higher than 10 g/l.</p> |
