NOM removal in artificial watersFrom batch experiments to model

April – July 2009

Leonard Galais

Supervisor : Anke Grefte

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What is NOM ?

assimilable organic carbon over the treatment plant

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influentozone

influentsoftening

influentactivatedcarbon

influentslow sandfiltration

clear water

AOC (ug/L)

•The Orange – brown color of water is mainly due to NOM

•NOM is everywhere from the treatment plant to the sewerage

network

•NOM is a complex and highly heterogeneous mixture of organic

compounds

•Humic and Fulvic acids stand for the major part of NOM

•NOM is entirely due to chemical and biological degradation organics

compounds

•NOM is negatively charged

09-07-2009

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What is IEX ?

•The most efficient way to remove dissolved ionic constituents

•LEWATIT® and MIEX®

•strong base activity

•macro porous structure

•pre-treatment of raw water with efficient IEX resins may increase by a factor 10 the life time of downstream

GAC filters (A. Grefte, 2007) Zoom on IEX particules

09-07-2009

Aims

3/1109-07-2009

•Is it possible to measure and identify the different humic substances with S::can and DOC?

•How are they removed by IEX?

4/11

S::canMeasuring UV254 absorbance

UV254

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solutions

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s (

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DOC measurementsA different point of view

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SRHA-5

SRFA-5

NAHAR-5

NAFAR-5

OA-0,5

AA-0,5

FA-0,5

SRHA-3

SRFA-3

NAHAR-3

NAFAR-3OA-1

AA-1FA-1

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2,5

UV254

DOC

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UV254

DOC

ads acids

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NAHAR-3 AV

OA-10 AV

FA-10 AV

FA-5 AV

AA-10 AV

AA-5 AV

NAHAR-4 AV

NAHAR-2 AV

NAFAR-4 AV

NAFAR-2 AV

SRHA-4 AV

SRHA-2 AV

SRFA-4 AV

SRFA-2 AV

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Untreated solutions - 1 ADS

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255 322,5 447,5 572,5 697,5

UV lenght

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OA - 1

OA - 5

DEMIW

OA - 0,5

ADS fulvic acids / humic acids

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UV lenght

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NAFAR 5 AV

NAHAR 5 AV

SRFA 5 AV

SRHA 5 AV

Comparing artificial solutions of acids

09-07-2009

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concentration (mg/ L)

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s (

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SRHA

SRFA

NAHAR

NAFAR

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Untreated solutions - 2 Comparing curves and Looking for relations

09-07-2009

Is it possible to predict the UV spectrum of an unknown concentration solution by combination ?

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wavelenght (nm)

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cm

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NAHAR 5-3

NAHAR-2 AV

Error : 22%

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Batch experiments - 1UV254 absorbance over the time

09-07-2009

Adsorbance over the time for 10 mg/L solutions of humic and fulvic acids

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time (hours)

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s (

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SRHA SRFA NAHAR NAFAR

67%

37%

26%

60%

NAFAR A series

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1015202530

samples

UV

(1/c

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0123456

DOC (mg/L)

UV AV

DOC value

9/11

Batch experiments - 2Influence of the resin amount

resin efficiency

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amount of resin (mg) in 1/2L

UV

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s (1

/cm

) SRHA

SRFA

NAHAR

NAFAR

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ModelingAre we able to predict breakthrough curves ?

09-07-2009

SRHA predicted breakthrough curve

Conclusions

11/11

• Acids are not measurable with UV, neither with DOC.

• DOC and UV measurements are different for Humic and Fulvic substances.

• Fulvic substances are better removed by IEX.• To remove 50% of NOM, you may regenerate IEX

every 3 weeks at least.

09-07-2009

NOM removal in artificial watersFrom batch experiments to model

April – July 2009

Leonard Galais

Supervisor : Anke Grefte