Effect of NO-2 on N2O production by NH+4 and NH2OH oxidation during nitritation process - Details

Author：

Liu, Yue (Liu, Yue.) | Peng, Yi (Peng, Yi.) | Li, Pengzhang (Li, Pengzhang.) | Hou, Hongxun (Hou, Hongxun.) | Peng, Yongzhen (Peng, Yongzhen.) (Scholars：彭永臻)

Indexed by：

EI PKU CSCD

Abstract：

Nitrous　oxide　(N2O)　is　one　of　the　most　important　greenhouse　gases,　about　265　times　stronger　than　carbon　dioxide　(CO2),　and　it　may　also　destroy　the　ozone　layer.　In　the　biological　wastewater　treatment　process,　autotrophic　nitrification　has　been　thought　to　be　the　major　source　of　N2O　production.　So　it　becomes　increasingly　important　to　prevent　N2O　emission　from　sewage　treatment.　In　this　study,　by　adding　NH+4,　NH2OH　and　NO-2　to　the　effluent,　the　effect　of　NO-2　on　N2O　production　by　NH+4　and　NH2OH　oxidation　during　the　nitritation　process　was　investigated　in　a　laboratory　batch-scale　system　with　activated　sludge　for　treating　domestic　wastewater.　Within　the　first　30　min　of　NH+4　and　NH2OH　oxidation　process　(total　test　time:　180　min)　N2O　accounted　for　more　than　25%　of　the　total　production.　As　NH+4　or　NH2OH　was　consumed　completely,　the　amount　of　N2O　net　production　reduced　to　less　than　0.2　mgL-1　in　the　last　30　min.　Furthermore,　the　concentration　of　NO-2-N　could　affect　N2O　production.　The　increase　of　NO-2-N　would　promote　generation　of　N2O.　The　maximum　total　N2O　net　production　was　6.86　mgL-1　when　the　concentration　of　NO-2　was　60　mgL-1.　NH2OH　oxidation　played　a　key　role　in　N2O　production　at　the　very　beginning　of　the　experiment　while　nitrifier　denitrification　became　a　main　pathway　later.　When　the　domestic　sewage　was　treated　under　DO　limited　conditions,　due　to　the　presence　of　COD,　there　might　occur　heterotrophic　denitrification　during　the　aeration　phase.　However,　oxygen　and　NO-2　had　strong　inhibition　on　the　activity　of　nitrous　oxide　reductase　(NOS),　consequently　N2O　could　not　be　reduced　to　N2　completely.　It　led　to　more　than　17%　N2O　was　produced　and　the　maximum　total　net　production　reached　11.07　mgL-1.　Hence,　the　contribution　to　N2O　produced　by　denitrification　could　not　be　ignored　during　the　domestic　wastewater　treatment.　Besides　co-existence　of　NH+4　and　NH2OH　could　significantly　increase　N2O　production　and　this　process　also　emitted　more　N2O　when　the　concentration　of　NO-2　was　increased.　©,　2015,　Chemical　Industry　Press.　All　right　reserved.

Keyword：

Nitrogen oxides Denitrification Ozone layer Chemical oxygen demand Oxidation Wastewater treatment Sewage Sewage aeration Effluents Greenhouse gases Biological water treatment Activated sludge process Carbon dioxide Nitrification

Author Community：

[ 1 ] [Liu, Yue]Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing; 100124, China
[ 2 ] [Peng, Yi]Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing; 100124, China
[ 3 ] [Li, Pengzhang]Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing; 100124, China
[ 4 ] [Hou, Hongxun]Anhui Guozhen Environmental Protection Energy-Saving Technology Limited Liability Company, Hefei; Anhui; 230088, China
[ 5 ] [Peng, Yongzhen]Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing; 100124, China

Reprint Author's Address：

彭永臻
[peng, yongzhen]key laboratory of beijing for water quality science and water environment recovery engineering, engineering research center of beijing, beijing university of technology, beijing; 100124, china

Email：

Show more details

Related Keywords：