Influence of fermentation liquid of food-waste on nitrification based on K_La and OUR in SBR

The influence of fermentation liquid of food-waste to NH₄⁺-N reduction rate of SBR was investigated by comparison with sodium acetate, and batch experiments were carried out to find the changes of K_La and OUR under different carbon source dosages. It was found that NH₄⁺-N concentration rose to 0.9 mg/L slightly when food-waste was added, and sodium acetate had no significant impact on NH₄⁺-N remove rate; saturated DO and K_La declined with the increase of food-waste and acetate dosing quantity, food-waste had a less influence on oxygen transfer ability than acetate. DO could be maintained at 6 mg/L which met the demand of nitrification when food-waste concentration was 300 mg/L COD. OUR of food-waste was 25.1% smaller than acetate,while 52.3% smaller at the AOB oxygen uptake phase. It indicated that the addition of food-waste affected the activity of nitrobacteria especially AOB.