Microbiology in anaerobic wastewater treatment
Transcript of Microbiology in anaerobic wastewater treatment
© Sara Hallin
Microbiology in anaerobic
wastewater treatment
Sara Hallin
Department of Microbiology, SLU
Luftning är dyrt och energikrävande. Optimerad luftning kräver DO-mätare och reglering (komplicerat). Minska luftningen genom att införa anaeroba reningsprocesser: - Andra mikroorganismer
Ae
rob
ic v
s an
aero
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de
grad
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of
org
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Aerob Respiration (organotrof)
H20
Fermentation (organotrof)
ATP
8 NADH 2 GTP
6 CO2
Glukos
2 ATP 2 NADH
Glukolys
2 Pyruvat
Citronsyra cykeln 2 FADH
O2
NADH
FADH ATP
ATP
Fermentationsreaktioner
Pyruvat
AcCoA
Laktat
Acetate
Etanol
Acetaldehyd NADH
NAD+
NADH
NAD+ ATP
Redox
+
Glukos
2 ATP 2 NADH
Glukolys
2 Pyruvat
-
Anaerobic degradation
Biogas reactor or upflow anaerobic reactor
Ex) biogas production
Anaerobic digestor Biogas
Fertilizer
Waste
NH3 NO2- NO3
-
N2O
NO
NO2-
Organic nitrogen org-NH2
N2
N-fixation
Nitrification
Mineralization
AIR SOIL/WATER
Denitrification
Dissimilatory nitratreduction to ammonium (DNRA)
N-cycle
Assimilation
Assimilation
NH3 NO2- NO3
-
N2O
NO
NO2-
Organic nitrogen org-NH2
N2
N-fixation
Nitrification
Mineralization
AIR SOIL/WATER
Denitrification
Dissimilatory nitratreduction to ammonium (DNRA)
N-cycle
Assimilation
Assimilation
N2H2
Anammox
NH2OH
Delft, NL
Anaerobic Ammonia Oxidation: Anammox
Uncharacterized organisms from wastewater treatment or nitrate rich sludge can oxidize ammonia to N2 under anaerobic conditions (1995).
5NH4+ + 3NO2
- 4N2 + 6H2O + 2H+
The organisms grow autotrophically using CO2.
No aeration needed!
Anammox
Denitrifier Diversity
Bacteria Eukarya Archaea
Tree of Life
Andra anaeroba reningsprocesser
Heavy metal removal
• Promote sulfate reducing bacteria for removal of metals. • Sulfate is an electron acceptor in anaerobic respiration.
Oxidation of sulfide to elemental sulfur by chemotrophic bacteria. • The elemental sulfur precipitated from the wastewater can be collected for reuse in industry. • Sulfide oxidation reactors can also be used to clean gas streams which contain hydrogen sulfide (H2S).