Nitrate and nitrite injection during municipal solid waste anaerobic biodegradation.
Nitrified leachate recirculation has been proposed as a promising strategy for sustainable landfill management. In four test reactors, nitrate or nitrite was added (250 mg N-NO(x)(-)L(-1)) during municipal solid waste biodegradation. Nitrogen-oxides reduction reactions were monitored. Denitrification was the main nitrogen reducing reaction observed. On one hand, during the acidogenic waste degradation phase, as high amounts of volatile fatty acids (VFA) were present, nitrogen-oxides reductions were interpreted as heterotrophic denitrifications. On the other hand, denitrification reactions occurring during the late methanogenic phase were accompanied by sulphate productions and, as VFA were not detected, it was probably an autotrophic reaction. Denitrification inhibition was observed once. Ammonium concentration increased suggesting the occurrence of a dissimilatory nitrate reduction to ammonium (DNRA). Statistical treatment of analytical data revealed that only H(2)S concentration had a significant negative effect on N(2) production in our system. NO production was observed once when nitrite was injected during the acidogenic phase resulting in a total waste degradation inhibition. These results indicate that the consequences of nitrified leachate recirculation in full-scale landfills need to be carefully examined especially during the acidogenic phase or in the presence of waste containing high quantities of sulphur.
Vigneron
Vassilia
V
Cemagref-HBAN, parc de Tourvoie, BP 44, 92163 Antony cedex, France.
Ponthieu
Marie
M
Barina
Giulia
G
Audic
Jean-Marc
JM
Duquennoi
Christian
C
Mazéas
Laurent
L
Bernet
Nicolas
N
Bouchez
Théodore
T
D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D019149:Bioreactors; D005602:France; D005740:Gases / Q000737:chemistry; D009566:Nitrates / Q000737:chemistry* / Q000378:metabolism; D009573:Nitrites / Q000737:chemistry* / Q000378:metabolism; D009584:Nitrogen / Q000737:chemistry / Q000378:metabolism; D010084:Oxidation-Reduction; D012037:Refuse Disposal / Q000379:methods*; D013997:Time Factors
D005740:Gases; D009566:Nitrates; D009573:Nitrites; D009584:Nitrogen