It is difficult to achieve biological deep denitrification of wastewater due to low content of biodegradable organic matter in tail water from sewage treatment plant.If the tail water discharged into rivers

the eutrophication could be produced due to higher concentration of total nitrogen.Therefore

the study on deep denitrification technology is of important significance for tail water treatment.In this paper

the total nitrogen(TN) removal efficiency of a catalytic electric-oxidation technology and its influence factors

such as electric-current density

HRT

influent pH

etc.

were studied and analyzed.The results showed that total nitrogen can be decreased to 11.91 mg·L-1 from 26.40 mg·L-1(54.9%)

NO3--N to 4.90 mg·L-1 from 18.03 mg·L-1(72.8%) by the catalytic electric-oxidation technology at conditions of current density 32.67 mA·cm-2

pH 6.25—7.02

and HRT 30 min.The NO3--N removal is dominating in the TN removal of tail water from urban wastewater treatment plant.The results indicate that TN of tail water can be removed efficiently by this technology.The catalytic electric-oxidation technology is of the advantages of operation stability and shock resistance etc.

and could be a basis for advanced nitrogen removal of tail water from wastewater treatment plant.