Pilot scale evaluation of sludge reduction techniques at a TMP/newsprint mill

Sludge yield during the activated sludge treatment of TMP/newsprint effluen t was reduced by 15%, 35% and 43%, by applying UV conditioning, anoxic cond itioning and anoxic plus UV conditioning, respectively. The reduction capab ilities of these sludge treatments were more pronounced when the treatment system was operated at a shorter sludge age (nine days), as opposed to a lo nger sludge age (19 days). Treatment performance was unaffected by sludge c onditioning.