Method for culturing aerobic granular sludge for treating biological nutrients in municipal sewage

The invention relates to a method for culturing aerobic granular sludge for treating biological nutrients in municipal sewage, which comprises two reaction stages: (1) flocculent activated sludge is added in a sequencing batch reactor (SBR) as seed sludge, the domestic sewage is fed in the SBR which automatically operates according to the mode of water inlet-aeration-hypoxia-secondary aeration-precipitation-drainage, activated carbon powder and Mg2+ are added in the domestic sewage in the fourth day or fifth day after culturing, 10-20 days are needed in the stage, and the aerobic granular sludge with organism-removing and synchronous denitrifying capability can be obtained after 30-60 cycles; and (2) the SBR automatically operates according to the mode of water inlet-anaerobic mixing-aeration-precipitation-drainage-standing, 10-15 days are needed in the stage, and the aerobic granular sludge with high-efficient and synchronous denitrifying phosphorus-removing capability can be obtained after 20-45 cycles. In