Anammox for nutrient nitrogen removal from sludge liquors Dept. Chemical & Environmental Engineering University of Arizona Jim Field, Guangbin Li and Reyes Sierra Industrial Partners: Pima County Regional Wastewater Reclamation Department (PCRWRD) Los Angeles County Sanitation District (LACSD) 1
32
Embed
Anammox for nutrient nitrogen removal from sludge liquors Fiel… · mineralization. O 2. e-O. 2. e-N-fixation. Anammox. Discovered in Late 1980’s in The Netherlands. Simplified
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Anammox for nutrient nitrogen removal from sludge liquors
Dept. Chemical & Environmental EngineeringUniversity of Arizona
Jim Field, Guangbin Li and Reyes Sierra
Industrial Partners: Pima County Regional Wastewater Reclamation Department (PCRWRD)
Los Angeles County Sanitation District (LACSD)
1
The N Cycle
2
NH4+N2
NO2-
NO3-
Org-Nmineralizationas
sim
ilatio
n
O2
O2e-
e-
N-fixation
nitrification-denitrification
Costs N Removal
Conventional Nutrient N Removal Costs
Nitrification:
Denitrification: NO3- + 5 e- eq → 0.5 N2
64 g O2 / mol N
40 g COD/ mol N
3
Conventional Nutrient N Removal
DenitrificationAOBNitrification
NOB
N2
NH4+ NO3-
AOB
NOB
O2 COD
ammonia nitrate
dinitrogen gas
The Missing Link in the N Cycle
4
NH4+N2
NO2-
NO3-
Org-N
anammox
mineralizationas
sim
ilatio
n
O2
O2e-
e-
N-fixation
Anammox
Discovered in Late 1980’s in The Netherlands
Simplified Stoichiometry
5
N2NH4+ NO2-ammonia nitrate dinitrogen gas
+
Anaerobic Ammonium Oxidation
Nitrate was mixed with anaerobic effluent at Gist Brocadus to oxidize hydrogen sulfide and anammox was discovered due to NH4
+ in wastewater
Costs and Savings of AnammoxAnammox Reaction (Detailed Stoichiometry)
NH4+
(100% N)
57% flow
43% flow
57% less O2
no O2 needed for anammox
NitritationAnammox
N2 89% NNO3
- 11% NAOB
NO2-
no COD needed for anammox
6
Anammox is combined with AOB as a technology
O2 No COD
Issues with Anammox
pH optima are critical
Sensitive to Substrate (NO2-) Toxicity
H2S is very toxic
Sensitivity depends heavily on physological status cells
Low pH exacerbates NO2- stress
High pH slowly deactivates anammox
Slow growthe rate
Arizona has high sulfate levels in municipal wastewater 7
Doubling times range from 5 to 15 d
Toxicity of NO2-
starved/NO2- pre-exposure
NO2- pre-exposure
active
starved/active
Physiological status
8
Is it Possible to Cultivate Anammox from Return Activated Sludge (RAS)?