Selection And Research Of The Denitrification Carbon Source In The Process Of Nitrogen And Phosphorus Removal

A new approach to screen denitrification carbon sources was obtained in this research. Effective denitrification carbon sources could be selected by comparing the C/N values of material leaching liquor. In this paper, the C/N and C/P values of six materials were studied as follow, reed straws, yellow and green leaves of Chinese parasol, tachibana leaves, corn straws and corncobs. Furthermore, fresh leaves should be taken as the research object when leaves were denitrification carbon sources. Among of the non-leaves materials, the C/N and C/P values of corncobs were the highest; among of the leaves materials, the C/N and C/P values of tachibana leaves were the highest. An experiment was carried out by taking domesticated sludge as denitrifying mud, corncobs and tachibana leaves as denitrification carbon sources. The results showed that both corncobs and tachibana leaves could provide carbon sources continually, in addition, the nitrogen removal effect of tachibana leaves was better than that of corn cobs, but the phosphorus removal ability of corncobs was stronger than that of tachibana leaves. Both of them could realize denitrification, the nitrogen removal effect would be improved with the increase in dosage, the effluent COD would rose with the reaction time extending, but the concentrations of ammonia nitrogen and nitrate nitrogen were low in the effluent. The experiment of scanning electron microscopy (SEM) showed that the external corncob cross-sections and the back of tachibana leaves were the most suitable biofilm carriers. Corncobs and tachibana leaves were good potential denitrification carbon sources.