* METlab, Depa men o En i onmen al Enginee ing, Technical Uni e si y o Denma k Building 115, 2800 Kongens Lyngby, Denma k
** Depa men o Chemical Enginee ing, Uni e sidade de San iago de Compos ela, 15782, San iago de Compos ela, Spain
1 co esponding au ho : b ape@en .d u.dk;
1. INTRODUCTION
Model-based op imiza ion o bio ilm based sys ems pe o ming
au o ophic ni ogen emo al using he comp ehensi e NDHA model
Bo ja Val e de-Pé ez*,1, Yunjie Ma*, Ma in Mo se *, Ca los Domingo-Félez*,
Miguel Mau icio-Iglesias**, Ba h F. Sme s*
Re e ences:
[1] Volcke e al. Wa e Science and Technology 56.9 (2007): 117-125.
[2] Mulde e al. FEMS mic obiology ecology 16.3 (1995): 177-183.
[3] Domingo-Félez e al. En i onmen al Science: Wa e Resea ch & Technology 2.6 (2016): 923-930.
[4] Blum, J.M., e al., 2017. The pH dependency o N-con e ing enzyma ic p ocesses, pa hways and
mic obes: e ec on ne -N2O p oduc ion. In p ess, En i onmen al Mic obiology.
[4] Vangsgaa d e al. Wa e Science and Technology 67.11 (2013): 2608-2615.
2. MODEL DEVELOPMENT
1D model combining NDHA [3], Ad ec ion-Di usion app oxima ion and pH sol e
pH modeling:
•B en -Dekke me hod
•Gua an eed con e gence
•pH a ec s mic obial ac i i y by
•Impac on enzyma ic
ac i i y and basic cellula
unc ions [4]
•Specia ion o subs a es and
inhibi o s
PN/A based ea men has many bene i s:
•Lowe ae a ion cos s (63% [1])
•Lowe sludge p oduc ion (90% [2])
Ce ain ope a ional condi ions cause
N2O emissions which could o se he
ca bon oo p in o PN/A!
PDE-sys em disc e ized in space
Two-scale model:
•CSTR wi h biomass g own as bio ilm
•Bulk and bio ilm connec ed ia mass
ans e esis ance (bounda y laye )
Technical Uni e si y o Denma k
ACKNOWLEDGEMENTS
4. RESULTS
Objec i es:
1) De elop a model o p edic N2O emissions
om bio ilm Anammox eac o s
2) De ine op imal ope a ional condi ions o
maximum ni ogen emo al and minimum N2O
emissions
The wo k has been pa ially unded by The Danish Council
o Independen Resea ch Technology and P oduc ion
Sciences (FTP) (P ojec N2Oman, File No. 1335-00100B).
@Me lab_DTU
G anula Based Reac o
•La ge g anules suppo Anammox g ow h and lead o NOB supp ession
•Lowe N2O emisions in big g anules. N- emo al is educed compa ed o S1
•A high oxygen load Anammox a e ou compe ed and all ammonia is ni i ied and
N- emo al is low
•Low pH caused inc eased N2O p oduc ion h ough he ND pa hway due o mo e
HNO2 accumula ion compa ed o S1 (no shown)
•High pH inc eases ee ammonia inhibi ion by AOB, dec easing he o e all N-
emo al
•High pH dec eases AnAOB ac i i y, leading o ni i e accumula ion
•Ni i e accumula ion leads o highe N2O emissions a high pH
3. SCENARIO ANALYSIS
E alua ion o pH and
g anule size (cons an
biomass concen a ion in
he eac o ) impac on
N2O emissions
Ni ogen loading (mg/Ld)
R=500µm
pH=8
R=1000µm
pH=7.5
R=500µm
pH=7.5
Ni ogen loading (mg/Ld)
Cell g ow h and
me abolism
S a i ied
g anula
bio ilm
G anules
Ae a ion
Bulk liquid
Bounda y
laye
pH calcula ion
Gas
s ipping
Loading and
discha ge
S1 S3
S2
•pH 7.5 p omo es a good balance be ween AOB and AnAOB enzima ic ac i i y
•500 µm adius p omo es AnAOB and gi es enough oxyge exposu e o AOB
•N2O p oduc ion is low a low ammonia oxida ion a es
•P ocess pe o mance is s able wi h high N- emo al and low N2O emissions unde
he op imal LO2/LNH and ammonia loading
LO2/LNH s N- emo al p o ing insigh in o he
op imal loading a io (in e ms o ni ogen
emo al) and he associa ed N2O emissions
