Sewage and wastewater denitrification process

The invention relates a sewage and wastewater denitrification process, belonging to the technical field of biological treatment of water, wastewater or sewage. The sewage and wastewater denitrification process comprises a treatment tank, wherein the treatment tank is connected with a feeding pipe, the feeding pipe is connected with a bacteria selecting tank, and sewage and sludge are uniformly mixed in the bacteria selecting tank and are conveyed into the treatment tank through the feeding pipe; an aeration region and a plurality of denitrification regions are distributed in the treatment tank, stirrers are arranged at different positions of the denitrification region and are used for pushing sewage and wastewater to circulate in a runner manner in the treatment tank; and treatment tank isconnected to a precipitating tank through a water outlet pipe. The sewage and wastewater denitrification process is applied to the sewage treatment and has the advantages of high denitrification efficiency, good contact effe