Calibration and evaluation of the prediction accuracy of a (micro- … · 2015. 7. 22. · 13 DTU Chemical Engineering, Technical University of Denmark Results of influent generator

Calibration and evaluation of the prediction accuracy of a (micro-pollutant) influent generator

Laura Snip, Xavier Flores-Alsina, Ignasi Aymerich, Lluis Corominas, Benedek Plosz, Ulf Jeppsson and Krist Gernaey

8/6/2015 PhD defence Upgrading the BSM framework with emerging challenges

2 DTU Chemical Engineering, Technical University of Denmark


• Materials & Methods: – Catchment – Pharmaceuticals studied – Influent generator – Calibration technique – Evaluation methods

• Results: – Calibration WWTP Puigcerdà

•  Traditional variables •  Pharmaceuticals

– Application of tool • Conclusion & Further perspectives



Catchment under study - Puigcerdà

• Wastewater from Spain and France • Widespread catchment (area of 100 km2) • No industry present • Population equivalent 16.000 PE

– Fluctuating due to touristic activities – Average flow rate of 4100-8300 m3/day – Organic load of 595-1785 kg BOD/day – Nitrogen load of 123-349 kg N/day

•  60% from Puigcerdà



•  Ibuprofen (IBU) and metabolite 2-Hydroxyibuprofen (IBU-2OH) – Non-steroidal anti-inflammatory compound – 6 hours body residence time – Excretion in urine, 15% IBU, 26% IBU-(2)OH

•  Sulfamethoxazole (SMX) and metabolite N-Acetyl Sulfamethazine-d4 (SMX-N4)

– Antibiotic – 10 hours body residence time – Excretion in urine, 14% SMX, 44% SMX-N4

•  Carbamazepine (CMZ) and metabolite 2-Hydroxy Carbamazepine (CMZ-2OH)

– Mood stabilising drug – 8-72 hours body residence time – Excretion in urine 1% and faeces 28 % as CMZ,

4% urine CMZ-2OH

Pharmaceuticals studied



Influent generator

HOUSEHOLDS (HH)

INDUSTRIES (IndS)

SEASONAL CORRECTION

FACTOR

RAINFALL

HOUSEHOLDS (HH)

INDUSTRIES (IndS)

SOIL MODEL

SEWER SYSTEM

MODEL ASM-X FRACTIONATION

TEMPERATURE

FLOW RATE MODEL BLOCK

POLLUTANTS MODEL BLOCK

TEMPERATURE MODEL BLOCK

TRANSPORT MODEL BLOCK

100-aH

aH

FIRST FLUSH EFFECT

MODEL

infiltration

PHARMACEUTICALS

Gernaey et al., 2011

Environ. Modell. Softw. 26(11)



• Flow rate – Dry and wet weather – Blocks HH, Rainfall, Soil and Sewer system

• Soluble pollutant, ammonium – Block HH

• Particulate pollutant, COD particulate – Block HH and First flush effect

• Temperature – Block Temperature

•  Automatic calibration procedure with Bootstrap

(optimisation of error)

1

1 2 3 3

Calibration technique

4



Evaluation methods

• Quantitative – Peak evaluation

•  Magnitude of peak •  Timing of peak

– Relative criteria •  Bias of prediction

– Overall criteria •  Index of Agreement

• Qualitative – Plot of the sequence of the normalised residuals

•  Part of the time-series

Dawson et al., 2007, Environ. Model. Softw., 22, 1034-1052

Hauduc et al., 2015, Environ. Model. Softw., 68, 196-204










•  Calibrated parameters: – HH: flow per QperPE = 110 m3/d; PE = 16,000 – Soil: area connected to sewer pipes – Sewer system: HRT = 3 h; – Rainfall: flow per mm rainfall = 824 m3/mm

October5 10 15 20 25 30Fl

ow ra

te (m

3 /day

)

05000100001500020000

Results of influent generator – Traditional compounds



Results of influent generator – Traditional compounds •  Ammonium and COD particulates •  Calibrated parameters:

– HH: •  Ammonium per day per PE = 5.53 mgN/(day.PE) •  COD particulate per day per PE = 57.11 mg/(day.PE)

–  First flush effect: •  Trigger flow rate = 10.000 m3/day •  Maximum accumulated mass = 700 kg/SS •  Fraction of settling particles = 0.40

October5 10 15 20 25 30N

H4+ lo

ad (k

g/d)

0100200300400500

October

5 10 15 20 25 30CO

D lo

ad (k

g/d)

0100020003000400050006000



•  Temperature – Average temperature, Tbias 17.7 ºC – Daily variation in temperature, TdAmp 0.38 ºC

–  Temperature decrease due to rain, Grain_Temp 0.14

Results of influent generator – Traditional compounds

October5 10 15 20 25 30Te

mpe

ratu

re (o C

)

81012141618



Results of influent generator – Pharmaceuticals - Ibuprofen

IBU IBU-2OH

Date11/10/2012 12/10/2012 13/10/2012

Pol

luta

nt lo

ad (g

/d)

0

20

40

60

80

100

120

140

Date11/10/2012 12/10/2012 13/10/2012

Pol

luta

nt lo

ad (g

/d)

0

20

40

60

80

100

120

140

•  Ratio IBU:IBU-2OH 1:0.6

•  Theoretical ratio 1:1.7

•  Different IBU administrations, waste of IBU, transformation in sewer, data uncertainty



Results of influent generator – Pharmaceuticals - Sulfamethoxazole

SMX SMX-N4

•  Considerably lower load than IBU and IBU-2OH •  Ratio SMX:SMX-N4 1:0.6 •  Theoretical ratio 1:3 •  Retransformation of SMX-N4 to SMX

Date11/10/2012 12/10/2012 13/10/2012

Pol

luta

nt lo

ad (g

/d)

0

2

4

6

8

10

Date11/10/2012 12/10/2012 13/10/2012

Pol

luta

nt lo

ad (g

/d)

0

2

4

6

8

10



Results of influent generator – Pharmaceuticals - Carbamazepine

CMZ CMZ-2OH

•  Different pattern due to different excretion paths •  Ratio CMZ:CMZ-2OH 1:3 •  Theoretical ratio 1:4 •  Desorption of CMZ, retransformation of CMZ-2OH

Date11/10/2012 12/10/2012 13/10/2012

Pol

luta

nt lo

ad (g

/d)

0

2

4

6

8

10

Date11/10/2012 12/10/2012 13/10/2012

Pol

luta

nt lo

ad (g

/d)

0

2

4

6

8

10



Results of influent generator – Qualitative evaluation - Traditional variables

Ammonium COD particulates

Flow rate Temperature

Data points0 250 500 750 1000 1250

Sequ

ence

of r

esid

uals

-10

-5

0

5

10

Data points0 250 500 750

Sequ

ence

of r

esid

uals

-30-20-10

0102030

Data points0 250 500

Sequ

ence

of r

esid

uals

-60

-40

-20

0

20

40

60

Data points0 250 500 750 1000 1250

Sequ

ence

of r

esid

uals

-400

-200

0

200

400



Results of influent generator – Qualitative evaluation - Pharmaceuticals

IBU SMX CMZ

IBU-‐2OH SMX-‐N4 CMZ-‐2OH

Data points0 2 4 6 8 10 12 14 16 18 20 22 24

Sequ

ence

of r

esid

uals

-10

-5

0

5

10

Data points0 2 4 6 8 10 12 14 16 18 20 22 24

Sequ

ence

of r

esid

uals

-10

-5

0

5

10

Data points0 2 4 6 8 10 12 14 16 18 20 22 24

Sequ

ence

of r

esid

uals

-10

-5

0

5

10

Data points0 2 4 6 8 10 12 14 16 18 20 22 24

Sequ

ence

of r

esid

uals

-10

-5

0

5

10

Data points0 2 4 6 8 10 12 14 16 18 20 22 24

Sequ

ence

of r

esid

uals

-10

-5

0

5

10

Data points0 2 4 6 8 10 12 14 16 18 20 22 24

Sequ

ence

of r

esid

uals

-10

-5

0

5

10

•  Similar results are obtained with quantitative evaluation methods



•  In-sewer transformations (Jelic et al., 2015 Wat. Res. 68, 98-108) – ASM-X transformation SMX (Plósz et al., 2010 Environ. Sci.Technol.

44, 734-742) –  Parameters estimated for activated sludge

– Ratio SMX:SMX-N4 with reactions 1:1.2 thus closer to theoretical ratio (1:3)

Results of influent generator – Application of tool

Estimated load

without reactions

(g/d)

Estimated loads with

reactions (g/d)

Difference in

estimation (%)

SMX 0.1227 0.1091 -11

SMX-N4 0.08 0.1281 +60










•  Influent generator can reproduce dynamics of ‘traditional’ variables and pharmaceuticals

•  Different pharmaceuticals show different occurrence at inlet of WWTP

•  The tool can extra- and interpolate time series •  In-sewer transformations can be taken into account when

back calculate consumption rates

Conclusion & Future perspectives - Pharmaceuticals



The research leading to these results has received funding from the People Program (Marie Curie Actions) of the European Union’s Seventh Framework Programme FP7/2007-2013 under REA agreement 289193. This presentation reflects only the author’s views and the European Union is not liable for any use that may be made of the information contained therein.

Thank you for your attention!

www.sanitas-itn.eu

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Calibration and evaluation of the prediction accuracy of a (micro- … · 2015. 7. 22. · 13 DTU Chemical Engineering, Technical University of Denmark Results of influent generator