Abstract:Oxygen nanobubble modified particles are widely used to increase oxygen at the sediment interface with polluted water bodies. In order to study its ability to aerate sediment interface and to remediate ammonia pollution, activated carbon was used as a supporting material to prepare oxygen nanobubble, and a column core culture experiment was used to study the effect of oxygen nanobubble modified activated carbon on the removal of ammonia nitrogen in river sediments. The results showed that the addition of oxygen nanobubble modified activated carbon to the SWI increased its dissolved oxygen (DO) concentration increased from 0.48 mg·L-1 to 6.10 mg·L-1, and its oxidation-reduction potential (ORP) increased from 34 mV to 19 mV. During the experiment, the diffusion gradients in thin-films technology was used to monitor the vertical concentration of ammonia nitrogen and nitrate at SWI. The addition of oxygen nanobubble modified activated carbon reduced the concentration of ammonia nitrogen in the overlying water from 1.65 mg·L-1 to 0.54 mg·L-1, removing 67.3%. The concentration of ammonia nitrogen in the sediment was reduced from 2.75 mg·L-1 to 0.73 mg·L-1, and the removal rate was 37.5%. The flux of ammonia nitrogen was reduced by 82.0%. Oxygen nanobubble modified activated carbon to promote the nitration reaction by the interfacial both oxygen, reducing the concentration of ammonia water, but also as a contact layer insulating cover overlying sediments with ammonia water, sediments reduce the release of ammonia. In this paper, the combined application of overlay technology and interface oxygen nanobubble aeration technology, the research results can provide basic data support for reducing the ammonia nitrogen load in the river.