International experience of biological removal of

Torresi Elena, Veolia Water Technologies-AnoxKaldnes, Herning 2020-09-01

International experience of biological removal of micropollutants, eXenoTM technology

I. How well do existing AK MBBR and HYBAS™ plant remove micropollutants?

II. eXeno™ technologies: overview of pilot plants

III. eXenO3™: polishing of ozonated wastewater with MBBR

Outline

2

• HRT ≠ SRT -> “Sludge retention time” on carriers very long and therefore very specialized biomass

• Improved efficiency due to adaptability to the toxic and shock conditions

• Customized treatment line with specialized biomass

Biofilms vs Activated sludge: What is the gain for the micropollutant

removal?

AnoxKaldnes™ HYBAS™

IFAS = Integrated Fixed Film Activated sludge= Activated sludge+ MBBR

MBBR= Moving Bed Biofilm Reactor

AnoxKaldnes™ MBBR

3

• Biofilms generally improve the biodegradation of medium and difficult degradable compounds

• What about our full-scale reference MBBRs and HYBAS™?

Biological removal with biofilm: AnoxKaldnes™ HYBAS™ and MBBR

4

I. How well do existing AK MBBR and HYBAS™ plant remove micropollutants?

5

Mainstream treatment process

• WWTP in Italy: MBBR vs AS

• WWTP in Sweden: HYBAS™ vs AS

Tertiary MBBR (for tertiary nitrification)

• MBBR in UK WWTP

• MBBR in IT WWTP

Full-scale MBBR and HYBAS ™ sampling campaign

6

Full-scale sampling of WWTP in Italy: MBBR vs AS

Exising CAS line

17 000 PE

MBBR line to 35 000 PE

- Increase capacity

- From carbon only to nitrogen

Removal of micropollutants in the lab-trial (WWTP in Italy)

8Increased degradation rates in MBBR line for 70% of the compounds

MBBR VS AS

Batch test results in the lab, spiking 21 substances

0 4 8 1 2 1 6 2 0 2 4

0 . 0

0 . 2

0 . 4

0 . 6

0 . 8

1 . 0

I o h e x o l

T i m e ( h )

Cw

/C

0

0 4 8 1 2 1 6 2 0 2 4

0 . 0

0 . 2

0 . 4

0 . 6

0 . 8

1 . 0

D i c l o f e n a c

T i m e ( h )

Cw

/C

0

ND:Not degradaded

Increasing k (biodegradation

kinetics) in MBBR compared

to AS:

+ : >30%

++ : 50-70%

+++: >100%

Compound % increase of k with MBBR

1-H-benzotriazole

5-cholobenzotriazole +++

5-methyl-1h-benzotriazole +

Atenolol +

Azithomycin

Bezafibrate

Bicalutamide ND

Carbamazepine ND

Citalopram +++

Claritomycin +

Clofibric acid +++

Diclofenac +++

Erythromycin

Hydrochlorothiazide ND

Iohexol ++

Ketoprofen +++

Metoprolol ++

Mycophenolic acid +++

Sertraline ND

Sulfamethoxazole

Venlafaxine +++

• 6 parallel lines

• 2 lines turned into HYBAS™ in 2012

• Sampling of carriers and sludge in the AS and HYBAS™ line

• Batch experiment with spiked micropollutants to compare suspended biomass only and suspended biomass and carriers together

Full-scale sampling of WWTP in Sweden: HYBAS™ vs AS

9

Biological removal in mainstream: AnoxKaldnes™ HYBAS™

10

HYBAS™ VS AS

Batch test results in the lab, spiking 21 substances

0 4 8 1 2 1 6 2 0 2 4

0 . 0

0 . 2

0 . 4

0 . 6

0 . 8

1 . 0

I o h e x o l

T i m e ( h )

Cw

/C

0

0 4 8 1 2 1 6 2 0 2 4

0 . 0

0 . 2

0 . 4

0 . 6

0 . 8

1 . 0

D i c l o f e n a c

T i m e ( h )

Cw

/C

0

Biofilms generally improve the biodegradation of

medium and difficult degradable compounds

Compound % increase of k with HYBAS™

1-H-benzotriazole ++

5-cholobenzotriazole ++

5-methyl-1h-benzotriazole +++

Atenolol +

Azithomycin +++

Bezafibrate ++

Bicalutamide ND

Carbamazepine ++

Citalopram +++

Claritomycin ++

Clofibric acid +++

Diclofenac +++

Erythromycin ++

Hydrochlorothiazide ND

Iohexol +++

Ketoprofen ++

Metoprolol +

Mycophenolic acid ++

Sertraline +

Sulfamethoxazole +

Venlafaxine +

ND:Not degradaded

Increasing k (biodegradation

kinetics) in MBBR compared

to HYBAS™:

+ : >30%

++ : 50-70%

+++: >100%

MBBR for tertiary nitrification –MBBR Plant in UK

11

Treated effluent

A

B

Influent

Municipal WWTP

Tertiary removal to achieve more stringent limits of NH4-N effluent concentration (NH4-N < 1 mg/l)

Patended flow pattern rotated to ensure even biofilm development between the two tanks, and maximize operation performance (nitrification removal) in the 2 MBBR tanks

Effluent

MBBR for tertiary nitrification –MBBR Plant in UK

12

Treated effluent

Influent

Municipal WWTP

Effluent

A

B

Tertiary removal to achieve more stringent limits of NH4-N effluent concentration (NH4-N < 1 mg/l)

Patended flow pattern rotated to ensure even biofilm development between the two tanks, and maximize operation performance (nitrification removal) in the 2 MBBR tanks

Full-scale campaign:

• Only 11 measured compounds over 23 targeted micropollutants

• Removal >25% for most of the detected pharmaceuticals (process not optimized for micropollutants but only to remove NH4-N down to 1 mg/l)

13

MBBR for tertiary nitrification - Results from MBBR Plant in UK

0 2 0 4 0 6 0 8 0

S e r t r a l i n e

C i t a l o p r a m

V e n l a f a x i n e

C a r b a m a z e p i n e

5 - m e t h y l - 1 h - b e n z o t r i a z o l e

1 - H - b e n z o t r i a z o l e

M e t o p r o l o l

E r y t h r o m y c i n

5 - c h o l o b e n z o t r i a z o l e

D i c l o f e n a c

B e z a f i b r a t e

A t e n o l o l

M y c o p h e n o l i c a c i d

M e a s u r e d

N D

Removal of the remaining compounds predicted by batch experiment

Potential high removal of

• very difficult X-ray contrast media Iohexol (>60%) : not present in full-scale

• mycophenolic acid, ketoprofen, atenolol (50%)

Additionally to tertiary removal of NH4-N (<1 mg/l), removal of micropollutants

14

MBBR for tertiary nitrification - Results from MBBR Plant in UK

0 2 0 4 0 6 0 8 0

S e r t r a l i n e

C i t a l o p r a m

V e n l a f a x i n e

C a r b a m a z e p i n e

5 - m e t h y l - 1 h - b e n z o t r i a z o l e

1 - H - b e n z o t r i a z o l e

M e t o p r o l o l

E r y t h r o m y c i n

C l a r y t h r o m y c i n

A z i t h o m y c i n

5 - c h o l o b e n z o t r i a z o l e

D i c l o f e n a c

B e z a f i b r a t e

A t e n o l o l

I o h e x o l

K e t o p r o f e n

M y c o p h e n o l i c a c i d

P r e d i c t e d

N D

N D

N D

N D

* ND: not degraded

• Two MBBR in series for teritary nitrification

• Use of oure O2 for oxygenation

• K1 were sampled in both stages• To investigate if different ammonia

loads will have an impact on the kinetics of micropollutants

MBBR for tertiary nitrification - WWTP Plant in Italy

15

MBBR for tertiary nitrification – Results from WWTP in Italy

16

0 4 8 1 2 1 6 2 0 2 4

0 . 0

0 . 2

0 . 4

0 . 6

0 . 8

1 . 0

B e z a f i b r a t e

T i m e ( h )

Cw

/C

0

0 4 8 1 2 1 6 2 0 2 4

0 . 0

0 . 2

0 . 4

0 . 6

0 . 8

1 . 0

C i t a l o p r a m

T i m e ( h )

Cw

/C

0

Higher potential removal of micropollutants in the first

stage MBBR: removal of micropollutants related to

ammonia load

0 1 0 2 0 3 0 4 0

C a r b a m a z e p i n e

H y d r o c h l o r o t h i a z i d e

S e r t r a l i n e

S u l f a m e t h o x a z o l e

1 H - b e n z o t r i a z o l e

5 - c h l o r o b e n z o t r i a z o l e

5 - m e t h y - 1 h - b e n z o t r i a z o l e

C l a r i t o m y c i n

D i c l o f e n a c

E r y t h r o m y c i n

I o h e x o l

A z i t h o m y c i n

M e t o p r o l o l

V e n l f a x i n e

M y c o p h e n o l i c a c i d

B e z a f i b r a t e

C l o f i b r i c a c i d

B i c a l u t a m i d e

K e t o p r o f e n

A t e n o l o l

C i t a l o p r a m

P r e d i c t e d B e r g a m o

N D

N D

N D

N D

* ND: not degraded

• Biofilms (MBBR or HYBAS™) generally improve the biodegradation of medium and difficult degradable compounds also at full-scale

• HYBAS™ seems to select for key bacteria specialized for removal of micropollutants

• Tertiary nitrifying MBBRs present already a fair removal potential of micropollutants

• Higher with higher ammonia load

• How to optimize those systems for micropollutants? ->eXeno™ technolgy

Key message of the full-scale campaigns

17

II. eXeno™ technologies: overview of pilot plants

18

1. Boosting of biomass growth through rotating flow pattern (patent of VWT)

2. Selection of microorganisms for micropollutants removal based on biofilm thickness control

3. Not only micropollutants but also tertiary nitrogen removal

eXenoTM - M solution for municipal wastewater

19

Influent Treated effluent

Municipal WWTPeXenoTM - M polishing technology

By-passed high loaded wastewater

Returned to WWTP

A B

C

eXeno™ piloting in DK and SE

20

LandskronaHerning

Assens

On going

eXeno™ piloting

21

Low COD/N load High COD/N loadHigh COD/N load

eXeno™ piloting

22

Low COD/N load High COD/N loadHigh COD/N load

Time (h)

C(µ

g/l)

0.00

0.25

0.50

0.75

1.00

Re

sid

ual

frac

tio

n (c

/c0)

Time (h)

Ibuprofen

0.00

0.25

0.50

0.75

1.00

Re

sid

ual

frac

tio

n (c

/c0)

Time (h)

Iohexol

0.00

0.25

0.50

0.75

1.00

Re

sid

ual

frac

tio

n (c

/c0)

Time (h)

Metoprolol

0.00

0.25

0.50

0.75

1.00

Re

sid

ual

frac

tio

n (c

/c0)

Time (h)

Atenolol

OxicAnoxicAnaerob

Resid

ual fr

action (

C/C

0)

K (

h-1

) *

10-3

Time (h)

eXeno™ piloting outcomes

Regeneration phase every 6-48 hoursLong starvation phase seems to improve biodegradability

5-15% of WWTP influent flow by-passed to regeneration line Intermittent aeration allows for nitrification and denitrification in the regeneration line

Design will be finilized with results from Mereff project!

eXenoTM for municipal wastewater effluents: results from trials

24

Efficiency tested for >20 pharmaceuticals in 2 pilots and lab tests through batch experiments and measuring campaigns

Biological removal of substances up to 80%Average removal of 10 substances of 50%

Removal of substances can vary depending ● on nitrogen and carbon loading applied during the

regeneration phase of eXenoTM operation ● on the duration of the regeneration phase and main

treatment line● HRT

III. eXenO3™: polishing of ozonated wastewater with MBBR

25

eXenO3TM - Hybrid solutions

26

Removal of transformation products created through ozonation

1st Reference in Germany (Warburg, 2017)2nd Reference in Germany (Rheda, 2020

Municipal WWTP

O3

WWTP Warburg

Project: Ozonation with MBBR-post treatment

Size: 120.000 PE

Flow: 662 m3/h

eXenO3TM - results from Warburg WWTP

27

Itzel et al. 2019. Evaluation of a biological post-treatment after full-

scale ozonation at a municipal wastewater treatment plant

Results from eXenO3TM at Warburg WWTP (Germany)

eXenO3TM

• 60% reduction in the number of features =

micropollutants

• Simultaneously, 241 new features were formed

by ozonation (transformation products TP,

mostly of carbamazepine, diclofenac, metoprolol,

terbutryn)

• TP elimination rate of 95% by the biological

post-treatment MBBR (ozonated TP not found

after MBBR)

28

Thank you!