Phosphorus removal and greenhouse gas N_2O emission in a lime-induced aerobic sludge granule process

摘要

Aerobic sludge granulation was achieved in an activated sludge process continuously fed with lime(Ca~2+ 100 mg l~-1 influent) every other day. Eighteen days after lime addition. Activated sludge granules with the size of 0.5-2.2 mm were formed, which occupied 10-25/100 of total sludge volume. Sludge volume index(SVI) was reduced to an average of 50 ml g~-1, which increased average sludge concentration to 3.6-5.0 g VSSI~-1, 1.6-2.1 times of that of control. Greenhouse gas N_2O emission was also significantly reduced: N_2O concentration from the lime-addition reactor was 5-15 ppmv, 47-61/100 of that of control.