In order to investigate the feasibility and denitrification performance of single stage oxic process

pulsed feeding was employed in sequence batch reactor(SBR)process for treating a real landfill leachate containing much ammonia nitrogen(NH4+-N).Three equal feeds were used in the pulsed SBR process containing four anoxic and three oxic stages.No extra carbon source was demanded in all fourth anoxic stage(An4)

and by use of internal carbon source from microorganism NO2--N was deoxidated into nitrogen(N2).The results indicate that the system is of stable and efficient performance of nitrogen removal after the acclimatization of activated sludge

as shown by continuous running of 118 days at 4 various total nitrogen(TN)concentration in influent.When chemical oxygen demand(COD)concentration in influent is a range of 733 mg稬-1 to 3971 mg稬-1

its concentration in effluent can be reduced to between 298 mg稬-1 and 888.15 mg稬-1

while TN concentration can be decreased from 299.78 mg稬-1 to 1100.34 mg稬-1 to between 13.89 mg稬-1 and 36.27 mg稬-1.The mean value of theoretical denitrification rate(TDNRm)by endogenous carbon for An4 is 1.53 mg N穐-1?(g MLVSS)-1.In a single cycle of operating phase

the endogenous denitrification rate(DNR)could be separated into two parts:fast one(DNR1)and slow one(DNR2)

the value of DNR1 in a single cycle of phase2(Ph2) could reach 2.80 mg N穐-1?(g MLVSS)-1.Advanced nitrogen removal of landfill leachate can be realized in the single stage oxic process under well-controlled conditions without physicochemical pre-treatment and demand of extra carbon source.