Msc Thesis about water

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Removal of Organic Micropollutants by Coagulation in

Wastewater Treatment

Tingyun Zhou

For the degree ofMaster of Science in Civil Engineering

Date of submission: June 2011Date of defense: June 30, 2011





Acknowledgements

First and foremost, I would like to thank my thesis supervisor Prof.dr.ir. Luuk C. Rietveld and

Dr.ir. Jaap de Koning from sanitary engineering department of TU Delft for allowing me join

OPTIMIX project, for their expertise, kindness, and most of all, the patience.

A special thanks to Dr.ir.S.I.de Castro Lopes from Nalco Europe for all the guideness and advice.

Also my great thanks and appreciation goes to ir. A. D. Schuit and ir.R.P. Andeweg Patrick fromwater lab of TU Delft, who helped and guided me, ―Miss trouble ‖ , through all the equipments,

methods of laboratory examination and transportation.

I would also like to thank Jeroen de Jong and Dr. Corine J. Houtman from Het Waterlaboratorium,

ir. David de Ridder and Dr.ir.A.R.D.Verliefde from TU Delft who guided and helped me with the

sample analysis which was the most tricky part during my thesis work.

Many appreciations also goes to my dear colleagues in the project, ir.Guido Kooijman and ir.

M.F.Mohd Amin, my work won ‘ t be completed without your daily support.

Finally, I owe special gratitude to my family and friends for contimuous and unconditional love

and support.



Abstract

The thesis study aimed to investigate the application of organic polymers as

coagulants/flocculants to remove the organic micropollutants from raw waste water.

Understand the mechanisms of pharmaceuticals removal by coagulation/flocculation. Determine

what organic flocculants are effective in removing different kinds of organic micro pollutants,

what the possibilities for phosphate and dissolved organic carbon (DOC) removal are.

During the proposed study an inventory was made of the experiences with different polymers

with respect to the removal of organic micro pollutants and phosphate.

Different polymers were selected and jar tests were performed, testing the different polymers

under different conditions: mixing condition, dose, pH. Then mechanism tests were performed in

3 types of matrices (tap water, 0.45µm filtered wastewater, raw wastewater) to find the removalmechanism of organic micro-pollutants and relations between the removal and characteristics of

polymers/pollutants.

It can be concluded that under current conditions polymer worked well on particle removal and

phosphorous removals were mainly along with particle removal. However, polymers do not

contribute significantly to remove the pharmaceuticals in both tap water and wastewater.



Nomenclature

BOD Biochemical Oxygen Demand [mg/l] COD Chemical Oxygen Demand [mg/l] C s Concentration of micro-pollutant in the sediments/sludge [ng/mg] C w Concentration of micro-pollutant in dissolved phase [ng/l]DOC Dissolved Organic Carbon [mg/l]

DWA Dry weather flow [m3

/day] f oc The fraction by weight of organic C in the sediments/sludge (TOC/TSS)HMW High molecular weight [-] HWL Het WaterlaboratoriumK d Sorption isotherms [l/mg] K oc Organic-C normalized partition coefficient [-]K ow Octanol-water partition coefficients [-]

LMW Low molecular weight [-]Log D pH7.4 pH corrected logK ow at pH 7.4 [-]MMW Mid molecular weight [-]MW Molecular weight [g/mol]N-total Total Nitrogen [mg/l] P-total Total Phosphorous [mg/l] SPE Solid phase extractionSUVA254 Specific UV Adsorption at 254 nm [cm -1]



List of Figures

Figure 1 a) Adsorptive coagulation, b) Bridging flocculation ....................................................... 3Figure 2 Overdosing of polymers results in destabilization ......................................................... 3Figure 3 Jar test equipment ........................................................ ........................................... 11Figure 4 (a) Location of Leiden ZW on the map of the Netherlands; (b) View of Leiden ZW (fromGoogle map) .................................................. ...................................................... ................. 14Figure 5 The photo of Filtration setup ................................................. ................................... 15Figure 6 Turbidity for 15 flocculants in terms of dosage (25~500ppm) ..................................... 22Figure 7 Turbidity for 15 flocculants at 12.5ppm dosage ................................................... ....... 22Figure 8 Turbidity for Coagulants+7757 in terms of dosage ..................................................... 22Figure 9 Turbidity for flocculants under various rapid mixing conditions .................................... 25Figure 10 Performance of 4 flocculants under various rapid mixing conditions........................... 26Figure 11 Turbidity for 4 flocculants under various slow mixing conditions ................................ 26Figure 12 Performance of 4 flocculants under 5mins/200rpm rapid mixing and various slowmixing .................................................. ...................................................... .......................... 27Figure 13 Turbidity removals for Nalco 71403 under various mixing conditions ......................... 28Figure 14 Turbidity removals for CORE SHELL 71305 under various mixing conditions ............... 28Figure 15 Turbidity removals for 77135+ An/Nonionic flocculants under various mixing conditions(50ppm+5ppm) ........................................................................ ............................................ 29Figure 16 Turbidity removals for all the combinations (50ppm+5ppm) ..................................... 29Figure 17 Turbidity, Ptot and PO 4-P removals by Nalco 71403 .................................................. 32Figure 18 Turbidity and PO 4-P removals by CORE SHELL 71305 ............................................... 32Figure 19 Turbidity for 77135 combinations under lower dosage .............................................. 33Figure 20 Lower dosage coagulant screening test graph ................................................... ....... 33Figure 21 The turbidity result of anionic/cationic combination dosage test ................................ 33Figure 22 Turbidity, Ptot and PO 4-P removal by 8190+7757 (anionic) ...................................... 34

Fi 23 T bidi P d PO 4 P l b 8190 71413 ( i i ) 34



List of Tables

Table 1 Applicable organic polymers for flocculation of wastewater ............................................ 4Table 2 Literature information on mixing times and intensity when dosing polymers ................... 5Table 3 Origin, type and pathways of organic micro pollutants (Hollender, 2008) ........................ 6Table 4 The characteristics of tested polymers .............................................. .......................... 13Table 5 Water quality of Leiden Zuidwest from 2007.8 to 2008.8 ............................................. 14Table 6 The properties of selected compounds ................... .................................................... 16Table 7 Overview of jar test setting in this study .................................................... ................. 18Table 8 Sample information and mixing conditions of Setting A ................................................ 21Table 9 Sample information of Setting B .............................................. ................................... 24Table 10 Mixing conditions of Setting B ............................................... ................................... 24Table 11 Sample information of Setting C ..................................................... .......................... 31Table 12 Mixing conditions of Setting C ............................................... ................................... 31Table 13 Optimal dosage and the performance for each candidate ........................................... 35Table 14 Sample information of Setting D ..................................................... .......................... 36Table 15 Mixing conditions of Setting D ............................................... ................................... 36Table 16 Sample information of mechanism tests ................................................... ................. 38Table 17 Mixing conditions of mechanism tests ...................................................... ................. 38Table 18 Sample information for pharmaceutical analysis ........................................................ 40Table 19 Measuring concentration of 15 compounds in pharmaceutical working solution ........... 41



Contents

ACKNOWLEDGEMENTS ........................................................................................................................... I

ABSTRACT .................................................................................................................................................. II

NOMENCLATURE .................................................................................................................................... III

LIST OF FIGURES .................................................................................................................................... IV

LIST OF TABLES ........................................................................................................................................ V

CONTENTS ................................................................................................................................................ VI

1. INTRODUCTION .................................................................................................................................. 1

2. THEORETICAL BACKGROUND ......................................................................................................... 2

2.1 COAGULATION / FLOCCULATION MECHANISMS........................................................................................... 2 2.1.1 Electrostatic coagulation .......................................................................................................... 2 2.1.2 Precipitation coagulation (or sweep coagulation) ................................................................ 2 2.1.3 Adsorptive coagulation ............................................................................................................ 2

2.2 ORGANIC POLYMERS.............................................................................................................................. 3 2.2.1 Organic polymer for coagulation/flocculation in water treatment ..................................... 3 2.2.2 Characterization of organic polymers .................................................................................... 4 2.2.3 Category ..................................................................................................................................... 4 2.2.4 Polymer dosage ........................................................................................................................ 4

2.3 COAGULATION / FLOCCULATION MIXING CONDITIONS FOR POLYMERS........................................................ 5 2.4 ORGANIC MICRO-POLLUTANTS................................................................................................................ 5

2.4.1 Definition and origins of organic micro-pollutants ............................................................... 5 2.4.2 Organic micro-pollutants in aquatic environments .............................................................. 6 2 4 3 O i ll i h ffl 7



4.2.1 General ......................................................................................................................................23 4.2.2 Testing conditions ...................................................................................................................24 4.2.3 Polymer dosage .......................................................................................................................24 4.2.4 Sample analysis .......................................................................................................................24 4.2.5 Results .......................................................................................................................................24 4.2.6 Conclusion ................................................................................................................................30

4.3 SETTING C – OPTIMAL DOSAGE TESTS ..................................................................................................30 4.3.1 General ......................................................................................................................................30 4.3.2 Testing conditions ...................................................................................................................31 4.3.3 Polymer dosage .......................................................................................................................31 4.3.4 Sample analysis .......................................................................................................................31

4.3.5 Results .......................................................................................................................................31

4.3.6 Conclusion ................................................................................................................................35 4.4 SETTING D – PH VARYING TESTS ..........................................................................................................35

4.4.1 General ......................................................................................................................................35 4.4.2 Testing conditions ...................................................................................................................35 4.4.3 Polymer dosage .......................................................................................................................36 4.4.4 Sample analysis .......................................................................................................................36 5.4.5 Results and conclusion ...........................................................................................................36

5. REMOVAL MECHANISM EXPERIMENTAL RESULTS ................................................................38

5.1 GENERAL ..............................................................................................................................................38 5.2 TESTING CONDITIONS ...........................................................................................................................38 5.3 PHARMACEUTICALS SPIKING ..................................................................................................................38 5.4 POLYMER DOSAGE AND PRICE ................................................................................................................39 5.5 S AMPLE ANALYSIS .................................................................................................................................39 5.6 R ESULTS ..............................................................................................................................................39 5.7 DISCUSSIONS AND CONCLUSIONS ..........................................................................................................44

6. CONCLUSIONS AND RECOMMENDATIONS ...............................................................................46





1. IntroductionWaste water treatment plants are an important source for emerging substances in theenvironment. Problems are caused by organic micro-pollutants (pharmaceuticals, pesticidesand other endocrine disrupting compounds) and heavy metals. The degree of removal ofthese compounds is low when they are dissolved or attached to colloids.

Different methods are available to remove these compounds such as ozonation and activatedcarbon filtration. However, these technologies are expensive in investment and operation.Therefore, it is proposed to investigate the possibility to remove the organic micropollutants

by coagulation/flocculation. The advantage of this method is that it can be combined withphosphate removal and that sludge removal can be enhanced during primary settling. Whenorganic flocculants (polymers) are used, this sludge can be used for energy regeneration.

The thesis study aimed to investigate the application of organic polymers ascoagulants/flocculants to remove the organic micropollutants from raw waste water.

Understand the mechanisms of pharmaceuticals removal by coagulation/flocculation.Determine what organic flocculants are effective in removing different kinds of organic micro

pollutants, what the possibilities for phosphate and dissolved organic carbon (DOC) removalare.

The cost and difficulty of sample analysis are taken into account to determine the organicpollutants to be tested. It is not practical to study all types of organic micro-pollutants in thewastewater. So pharmaceutical were decided to be the purpose removal objects in this study.

This study was included in a research project OPTIMIX and it was developed by TU Delft, TheRijnland Water board and Nalco Company in 2010.

hi fi l i f i b h l i fl l i



2. Theoretical Background

2.1 Coagulation/flocculation mechanismsColloidal particles found in wastewater typically have a net negative surface charge. They arestabilized due to the presence of an electrical double layer of ions and the resulting negativezeta potential. The viable method to remove colloids from wastewater is to destabilize thesuspension using chemicals. Regarding these destabilization and attachment processes, ageneral distinction is made between coagulation and flocculation (van Nieuwenhuijzen, 2002).

Coagulation indicates the process of charge neutralization resulting in destabilization of theparticles, while the term flocculation is used to indicate the process of complex formation thatis succeeding the destabilization. Three main mechanisms are described below:

2.1.1 Electrostatic coagulation

Electrostatic coagulation is the most important process when metal salts are applied. It iscaused by an increase in the electrolyte concentration in the wastewater suspension whenadding the metal salts. The amount of counter ions present in the diffuse part of the electricaldouble layer in the stable colloidal suspension increases, which causes destabilization of theparticles in suspension (van Nieuwenhuijzen, 2002). After dosing coagulant, the exterior ofthe colloidal particle is destabilized and can collide with other particles into removable flocs. Ifhigh dosages of coagulants are added, the concentration of ions in the diffuse layer mayincrease to such a level that the zeta potential shifts to a positive charge. In that case, theparticles will be positively charged and again be colloidal stable in suspension (Tchobanoglouset al., 2003).



Figure 1 a) Adsorptive coagulation, b) Bridging flocculation

Figure 2 Overdosing of polymers results in destabilization



However, there are some disadvantages such as higher costs in particular situations andenvironmental factors, and greater sensitivity to incorrect dosage.

2.2.2 Characterization of organic polymers

Organic polymers are generally characterized by two main properties: their molecular weightand the amount of ionic charge.

Molecular weight (WM)

The molecular weight is an indication for the amount of monomers and thus the length of thepolymer chain. The organic polymers could be divided in low molecular weight (LMW), midmolecular weight (MMW) and high molecular weight (HMW) corresponding to MW values inthe ranges: <10 5, 10 5-10 6 and >10 6 (Bolto et al., 2007).

Charge density

Polymers can be cationic, anionic and non-ionic. The charge density of the polymer indicatesthe amount of charge available to accomplish particle destabilization and flocculation. Previous research showed that cationic organic polymer can be used for flocculation of rawmunicipal wastewater. However, the addition of an anionic polymer did not show significantturbidity removal (van Nieuwenhuijzen, 2002).

Others

Additional to the molecular weight and the charge density, the structure of the polymer isimport. Besides the linear configuration, polymers can be manufactured cross-linked orbranched. Polymers are especially used in sludge dewatering by centrifuges because of theirability to resist high shear forces.



2.3 Coagulation/flocculation mixing conditions for polymersThe coagulation-flocculation process is influenced by raw water characteristics, temperature,pH, coagulant type and dose. However to avoid a poor performance the most importantparameters of mixing design must be considered: velocity gradient and mixing time.

In table 2 there is the literature information on mixing times and velocity gradients for jar testwhen dosing organic polymers.

Table 2 Literature information on mixing times and intensity when dosing polymers

Application Rapid mixingtime andintensity

Slow mixingtime andintensity

Reference

Jar test with municipalwastewater 1-2min 10-25min Udaya Bhaskar and Gupta

(1987)Jar test with municipalwastewater 20s-120s,800s -1 3min, 50s -1 van Nieuwenhuijzen (2002)

Jar test with municipalwastewater 2min, 300rpm 10min, 50rpm Pinto (2008)

Jar test with municipalwastewater 3min, 150rpm 5min, 50rpm Carballa.et al. (2005)Jar test with industrialwastewater 1min, 100rpm 2min, 25rpm Torres.et al.(1997)

Jar test with HA solution 2min, 250rpm 10min, 30rpm Hankins (2006)

Jar test with HA solution 1.5min, 102.5s -

1 15min, 11.8s -

1 Wei (2009)

Jar test with HA solution 3min, 200rpm 25min, 35rpm Moussas (2009)

Jar test with HA and PHA solution 5min, 100rpm 25min, 25rpm Rebhun (1998)

f



Table 3 Origin, type and pathways of organic micro pollutants (Hollender, 2008)

Source Substance groupsPathways in the

environment

Urban settlements

Personal care products, human pharmaceuticals,detergents, chemicals used in construction business(dyes, lacquer, binder, wood preservatives), flameretardants, pesticides, biocides

Wastewater DiffuseLandfill site

Agriculture Pesticides(insecticides, herbicides,fungicides),veterinary pharmaceuticals Wastewater Diffuse

IndustryIndustrial chemicals (polymers, dyes, varnishes,oxidants, reductants, detergents, corrosioninhibitors, biocides)

Wastewater Landfill site

Traffic Ingredients of motor oils, lubricants, combustionproducts Diffuse Landfill site

2.4.2 Organic micro-pollutants in aquatic environmentsIn aquatic environment, organic micropollutants can exist in a variety of forms: as a freelydissolved phase, as a colloidal phase or associated with sedimentary material (Warren et al.,2003).

Associated with suspended solid particles

The extent of sorption of a micro-organic compound onto a given sediment, as given by the

d



The relationship between K ow and K oc values has been found by several authors (Kenaga andGoring, 1980; Lyman et al., 1982; Karickhoff, 1984; Grathwohl, 1990) to be of the form:

log K oc= a log K ow – y

Thus in theory it should be possible to predict K d values from octanol-water partitioncoefficients and sediment fractional organic-C contents, and in general it is found that themore hydrophobic compounds (with the highest K ow) do exhibit the highest K oc(Warren et al.,2003).

Despite strong direct interactions with sediments, charged or highly-polar compounds stillgenerally exhibit lower K d values than non-polar non-ionic compounds, except on baremineral surfaces, owing to their much higher water solubility. Cationic compounds generallyinteract much more strongly with sediments than anionic ones, since ionisable organic-mattermoieties and mineral surfaces are generally neutral or negatively charged over the pH rangefound in the environment.

Interactions of micro-organics with dissolved organic matter

Natural colloidal organic matter, often referred to as dissolved organic C (DOC), has two maineffects on the distribution of micro-organic pollutants between aqueous and sediment-boundphases. These are ‗solubility enhancement‘ and the ‗solids concentration effect‘ (Warren et al.,2003).

Solubility enhancement is the reduction in the observed solid-solution distribution coefficient,K d, in the presence of DOC. This makes a compound appear to be more soluble in water, andreduces the total sediment- sorbed amount. The reason for the enhancement is that thecontaminants can also partition into hydrophobic domains in colloidal organic matter (Warrenet al., 2003).

d



2.4.4 Properties of organic pollutants

Several solute properties that influence organic pollutants adsorption are discussed. Theseproperties include solute hydrophobicity, partition coefficient, polarizability, molecularstructure.

Solute Hydrophobicity K ow

Solute hydrophobicity is often represented by the octanol – water partitioning coefficient (logK ow) (de Ridder et al., 2010). Large K ow values are characteristic of large hydrophobicmolecules which tend to be associated with solid organic matter while smaller hydrophilic

molecules have low K ow values [ICON, 2001].

Several authors have tried to directly relate log K ow to observed adsorption rates. Goodrelations between log K ow and adsorption rates were found in a system containinghydrophobic solutes and a hydrophobic adsorbent. A poor correlation was found when

hydrophobic partitioning is less relevant, i.e., when the solutes are small, hydrophilic and/orcharged/polar [de Ridder et al., 2010].

For ionic solutes, log K ow values were corrected for pH with respect to their H + dissociation/uptake. The pH-corrected log K ow values are referred to as log D (distribution coefficient). LogD values can be determined from log K ow values and the pKa values of the solute. For neutralsolutes, log K ow=log D; for ionic solutes log D < log Kow (de Ridder et al., 2010).

Organic carbon-water partition coefficients K OC



2.4.5 Statutory standards of micro-pollutants

Actual statutory standards for effluent of wwtp are not yet available for most organic micro-pollutants. There is a Dutch standard refers to the MAC (maximum permissible risk) forsurface water (source: RIVM, environmental quality, March 2009). The European standard isabout the standards for priority substances of the WFD (Source: Agreement prioritysubstances, Council of the European Union, June 23, 2008). However, for all used belownorms emphasize that these are standards for surface water and not standards for theeffluent of WWTP's. The MAC value of different substances for surface water could be used tocompare with the concentrations of the testing result in this study.

2.4.6 Organic micro-pollutants removal possibility by polymers

Removal pollutants by adsorption to particles

The sorption of organic contaminants onto the solids is determined by physicochemicalprocesses and can be predicted for individual compounds by the octanol-water partitioncoefficient (K ow). During the jar test, hydrophobic contaminants may partition onto settledsolids particles and compounds can be grouped according to their sorption behavior based onthe K ow value as follows:

Log K ow < 2.5 low sorption potential

Log K ow > 2.5 and < 4.0 medium sorption potential

Log K ow > 4.0 high sorption potential

Removal pollutants by binding with dissolved organic matter such as humic acid

Humic substances account for around 50% of the dissolved organic matter in natural water.



- During wastewater treatment, the compounds that consist of aromatic rings such asbenzo[a]pyrene, benzo[g,h,l]perylene, benzo[k]fluoranthene, mirex, benzo[b]fluranthene,

and benz[a]anthracene, showed a high removal of more than 85% by flocculation withalum and iron salts. However, the compounds such as diazepam, diclofenac, andmeprobamate, indicated the lowest removal (less than 10%). Alum as a coagulantresulted in a slightly better removal compared to ferric chloride coagulants. EDCs orPPCPs are removed by partially adsorbing on particles in water and metal hydroxideparticles formed during flocculation (Westerhoff et al., 2005).

- Dissolved humic acid (DHA) can be used as a complexing agent to remove hydrophobiccontaminants from water by complexation-flocculation process. Flocculation of DHA at

concentrations of 1-50 mg/l OC HA was highly efficient with both alum and ferric chloride.The proposed process is effective in removing pollutants of medium to highhydrophobicity (log K ow > 4.5) (Rebhun et al., 1998).

- Carballa et al. (2005) indicates that, in the sewage, compounds with high sorptionproperties (high logK d values), such as musks (Galaxolide and Tonalide) and Diclofenac,are significantly removed during coagulation – flocculation with efficiencies of 70% in thetemperature range of 12 – 25 1C. Lipophilic compounds, like musks, are mainly absorbedon the lipid fractions of the sludge, while acidic compounds, like Diclofenac, are mainly

adsorbed due to electrostatic interactions. Compounds with lower K d values, such asDiazepam, Carbamazepine, Ibuprofen and Naproxen, were reduced to a lesser extent(Diazepam and Naproxen), up to 25%, or not affected at any condition tested(Carbamazepine and Ibuprofen) (Carballa et al., 2005).

- Suarez et al. (2009) showed similar limited removal in hospital wastewaters. Highestefficiencies have been measured for musk compounds (HHCB, AHTN and ADBI) (>90%)which was attributed to their strong lipophilic character that enhanced their removal byabsorption. For ibuprofen, naproxen and diclofenac the maximum decrease in



3. Materials and MethodsDuring the proposed study an inventory was made of the experiences with different polymerswith respect to the removal of organic micro pollutants and phosphate. Then differentpolymers were selected and jar tests were performed, testing the different polymers underdifferent conditions: water quality, mixing condition, dose, pH.

After that, the results of the experiments were elaborated and find the removal mechanism oforganic micro-pollutants and relations between the removal and characteristics ofpolymers/pollutants.

3.1 Jar test procedureTo simulate conventional clarification, coagulation, flocculation and sedimentation steps wereperformed in a standard jar test apparatus according to KIWA (Figure 3). It consisted of sixbeakers with a volume of 1.8 L and stirrers, which could be adjusted to the same stirringconditions for all the beakers. The beakers were filled with 1.8 L of sample and thecoagulant/flocculant was added simultaneously to all beakers.





13

Table 4 The characteristics of tested polymers

Type Code Active constituents Appearance Solubility Charge MWTypical

concentrationin wastewater

Recommendedstock solutionpreparation

Cationicflocculant

NALCO 71403 Acrylamide based co-polymer Off-white liquid Emulsifiable Medium High <1%NALCO 71406 Acrylamide based co-polymer Off-white liquid Emulsifiable Medium High 0,01~0,05% <1%NALCO 71413 Acrylamide based co-polymer Off-white liquid Emulsifiable Medium~high High 0,01~0,05% <0.5%

CORE SHELL 71305 Acrylamide based co-polymer Opaque off-whiteemulsion Low High~very

high 0,2~0,5%

CORE SHELL 71303 Acrylamide based co-polymer Off-white emulsion Medium 0,2~0,5%

ULTIMER 7752 Acrylamide based co-polymer White liquid Dispersible Medium 0,5~2%ULTIMER 1460 Acrylamide based co-polymer Milky white Completely Medium 0,5~2%ULTIMER 1454 Acrylamide based co-polymer White/opaque liquid Completely Low High 0,01~0,1%

ULTIMER 71456 Acrylamide based co-polymer White liquid Completely Medium High 0,01~0,1%

ULTIMER 71458 Acrylamide based co-polymer White liquid Completely Medium High 0,01~0,1%

Anionicflocculant

NALCO 71601 Acrylamide based co-polymer Off-white liquid Emulsifiable Low High 0,01~0,05% <1%NALCO 71603 Acrylamide based co-polymer Off-white liquid Emulsifiable Low High 0,01~0,05% <1%NALCO 71605 Acrylamide based co-polymer Off-white liquid Emulsifiable Medium High 0,01~0,05%ULTIMER 7757 Acrylamide based co-polymer Milky white Completely Medium Medium 0,5~2%

Nonionicflocculant NALCO 71760 Acrylamide based homo-polymer Off-white liquid Insoluble High <1%

Coagulant

NALCOLYTE 7135 Amber liquid Completely 1~100ppmNALCO 8105 PLUS Light yellow liquid Completely It depends

CAT-FLOC 8103PLUS Polyelectrolyte Pale yellow~amber

liquid High Medium~High 1%

NALCO 77135 Aromatic heterocyclic compund,vegetable originated

Dark brow clearliquid Completely Medium Medium It depends

NALCO 8190 Polyampholytic Clear liquid Completely High 1~10ppm



3.3 Water samples

Raw wastewater from the municipal wastewater treatment plant of ―Leiden Zuidwest‖ wasused.

WWTP Leiden Zuid-West treats the water of 126,000 inhabitants living in the area of LeidenZuid-West, Voorschoten and Zoeterwoude-Dorp. The average daily flow is 24,000 m 3. At theWWTP first of all removal of coarse solids takes place followed by nitrification anddenitrification combined with chemical phosphorous removal and finally sedimentation(Scherrenberg et al.,2008 ).

(a) (b)

LeidenZuidwest wwtp



Figure 5 The photo of Filtration setup

Tap water

During the mechanism tests, tap water was also needed which was taken directly from thedrinking water tap in the lab at wwtp Leiden ZW.

3.4 Pharmaceuticals15 Pharmaceuticals were spiked and analyzed aiming to understand the removal mechanism.

Raw wastewater tap1μm filter 0.45μm filter 0.45μm filtrate

InletOutlet



16

Table 6 The properties of selected compounds (MW, log K ow, log D,polarizability, sum HB were deried from Chemspider; pKa were deried from Phys PropDatabase, 2004;concentration were deried from Broninventarisatie KRW-stoffen, 2009)

NO. Compounds MW(g/mol)

log K ow (-)

log D pH 7.4(-) pK a (-)

Polarizability(10 -24 cm 3)

sum HBda

DWA influent(µg/l)

DWA effluent(µg/l)

RWA influent(µg/l)

RWA effluent(µg/l)

1 atenolol 1 266.3 0.16 -1.66 9.6 29.438 92 bezafibrate 2 361.8 4.25 -0.14 n.a 38.05 7 0.21 0.05 0.08 0.053 carbamazepine 2 236.3 2.45 1.895 n.a. 27.625 4 0.9 0.77 0.25 0.264 clofibric acid 1 214.7 2.57 -0.9 n.a 21.11 4

5 diclofenac 2 296.2 4.51 1.437 4.15 30.339 5 0.35 0.32 0.1 0.196 gemfibrozil 2 250.3 4.77 1.77 n.a 28.5 4 1.02 0.33 0.33 0.227 ibuprofen 2 206.3 3.97 0.582 4.91 24.093 3 5.95 0.08 1.9 0.118 ketoprofen 2 254.3 3.12 0.41 4.45 28.462 6 <0.03 <0.039 metformin 1 129.2 -1.40 -3.82 n.a 13.22 10

10 metoprolol 2 267.4 1.88 -0.06 n.a 30.55 7 1.8 1.5 1.06 111 naproxen 2 242.2 3.18 0.347 4.15 26.372 4 3.45 0.24 1.13 0.1812 paracetamol 1 151.2 0.46 0.474 9.38 16.811 4

13 propranolol 1 259.4 3.48 0.785 9.42 31.312 5

14 sulfamethoxazole 2 253.3 0.89 -0.2 n.a. 24.75 9 0.39 0.12 0.12 0.0815 trimethoprim 2 290.3 0.91 0.473 7.12 31.817 11 0.28 0.16 0.08 0.1

1 Frequently detected from Dutch wastewater (van Beelen, 2007)2 Present in Leiden ZW (Broninventarisatie KRW-stoffen, 2009)



3.5 Jar test experiments5 phases of jar test experiments were performed:

Preliminary experiments

Setting A -- Screening test (with raw wastewater)

Select 6~8 candidates from the 20 different polymers (10 cationic flocculants, 4 anionicflocculants, 1 nonionic flocculant and 5 cationic coagulants).

Setting B -- Optimal mixing condition test (with raw wastewater)Perform the candidates that selected from Setting A under varying mixing conditions andobtain the optimal mixing conditions for each candidate. Then decide 4 final candidatesfor the further research.

Setting C -- Optimal dosage test (with raw wastewater)

Vary the dosage for the 4 candidates under the optimal mixing condition got fromSetting B to obtain the optimal dosage.

Setting D -- pH various test (with raw wastewater)

Compare the turbidity removal efficiency differences with varying pH (increase/decrease1 PH unit).

Mechanism experiments

Understand the adsorption mechanism for three removal possibilities of pharmaceuticals.



18

Table 7 Overview of jar test setting in this study

setting Sample PHRapidmixing

time(min)

Stirrervelocity

1 (rpm)

G-value1(s -1)

Slowmixing

(min)

Stirrervelocity

2 (rpm)

G-value2 (s -1)

Settlingtime

(min)

Numberof tests Remarks

A Screening tests (20 polymers)

Rawwastewater

dependon

samplequality

2 300 700 5 30 24

15

10 Select bestpolymers

BOptimalmixing

condition

4 flocculants and 15coagulant+flocculant

combinations

Rapidvaring 2/5 200/300 400/700 3 30 24

41

Obtainoptimalmixing

conditionSlow

varing2 200 400 5/10 30/50 24/505 200 400 1/3/5/10 30 24

C OptimalDosage

2 flocculants and2combinations

Jar test performed under optimal mixing condition of each candidateobtained from Setting B 19

Obtainoptimaldosage

D PH varyingtests

2 flocculants and 2combinations

PHvariation performed under optimal mixing condition and optimal dosage 2 See the pH

impact

Mechanismtests

2 flocculants and 2combinations

Raw+substances dependon

samplequality

performed under optimal mixing condition and optimal dosage 4

Understandtheadsorptionmechanismin different

types ofsample

Filtered raw+substances

Tap water+substances

Total 76



3.6 AnalysesBelow it is described the analyses performed on the supernatant of samples after the jar tests.The methods and definitions presented are based on Standard Methods (1998),Tchobanoglous et al (2003) and Merck procedures information review.

Turbidity

Turbidity in water traduces it quality regarding the presence of suspended solids (SS) andcolloidal matter, though a correlation of turbidity with the weight or particle numberconcentration of suspended matter is difficult. However, this parameter has been used as theprimary indicator of mainly general process efficiencies.

Turbidity was measured with 2100N Turbidity meter sell by HACH.

pH

The measurement of pH is defined as the determination of hydrogen ions activity in asolution, an important quality parameter of wastewater. Mostly all steps include inwastewater treatment, e.g., acid-basic neutralization, water softening, precipitation,

coagulation, disinfection and corrosion control are a function of pH-value.pH was measured with a pH meter (pH 197i from WTW) consisting of a potentiometer with atemperature-compensating device and accurate to 0.1 pH unit with a range from 0 to 14.

Temperature

The measurement of temperature is required in order to control the processes involvedduring coagulation and its chemical reactions and reaction rates. For instance, parameter asequilibrium constants, solubility products constants and specific reaction-rate constants are all



3.7 Sample preparation

For pharmaceutical analysis, before being sent to HWL, the samples were prepared (solidphase extraction) in the lab at TU delft.

The samples were collected in amber glass bottles prewashed by demi water. Solid phaseextraction (SPE) was conducted on a SPE Vacuum Manifold:

SPE cartridge (Oasis HLB 6cc/200mg) was conditioned with 2*5 ml methanol and 5 mldemi water.

Filtration column (Baker Disposable filtration column 6ml) filling with 1cm thick sea sandwas connected to the SPE cartridge. After that, wet the sand bed with demi water.

Sample (100 ml) was introduced to the filtration column and SPE cartridge via a PTFEtube.

After being washed with 5ml of 5.0% methanol solution, the cartridge was dried undervacuum for half minute and eluted with 2*4 ml methanol at a flow rate of 1 2 ml/ min.

The extracts were stored at 4 ℃ and then sent to HWL for analyze.



4. Preliminary Experimental ResultsJar tests were conducted to determine the feasibility and effectiveness of organic polymersfor flocculation of municipal wastewater.

4.1 Setting A – Screening tests

4.1.1 General

There are 20 polymers with different characristic (shown in Table 4) tested during thescreening test.

Turbidity has been used as the primary indicator of overall process efficiency (Abdessemed etal, 2000). Based on the turbidity removal efficiency, 5 candicates were selected to be testedduring the further study.

4.1.2 Testing conditions

All the polymers were tested under the conditions presented in table 8:

Table 8 Sample information and mixing conditions of Setting A

Experimentdate pH T

(◦C) Turbidity

(NTU)

Rapidmixing

time(min)

Stirrervelocity1 (rpm)

G-value1(s -1)

Slowmixing(min)

Stirrervelocity2 (rpm)

G-value2 (s -1)

Settlingtime(min)

2010/7/21~2010/7/23 7.29 21.52 133.44

2 300 700 5 30 24 15



Figure 6 Turbidity for 15 flocculants in terms of dosage (25~500ppm)



Flocculants

It can be concluded from Figure 6 and 7 that cationic organic polymers performed better thanan/nonionic polymers on turbidity removal with raw wastewater. In Figure 6, 15 polymerscould be distingished clearly into two groups at and above the dosage of 50 ppm: cationicpolymers (higher than 50% turbidity removal) and anionic polymers (lower than 50%turbidity removal).

Most of the cationic flocculants have the best turbidity removal at the dosage of 25ppm or50ppm. The turbidity removal decreased at the dosage of 125ppm, which is because of theoverdose of polymer resulting in destabilization of particles.

According to the criterias mentioned above, 6 candidates were selected:

- Nalco 71403, Nalco 71406: best performing products at lower dosages (25ppm and50ppm).

- CORE SHELL 71305, CORE SHELL 71303: forming larger flocs than other polymers,performing the best at 50ppm dosage (above 90% turbidity removal). Because of ahigher dosage than other polymers during the experiments, only tubidity removal at50ppm dosage could be compared with other polymers. In the further setting, these two

candidates were tested at lower dosage.

Coagulants

Figure 8 showed that, combining with flocculant (25ppm of ULTIMER 7757 ), the turbidityremoval of most of combinations increased with the increasing of dosage except Nalco 8190.The best performance of Nalco 8190 was at the dosage of 62.5ppm.

Obviously, Nalco 77135 performed quite well in the experiment at 62.5ppm and 125ppmdosage, and it could obtain 90% turbidity removal efficiency at a dosage of 62.5ppm. At the




The candidates were tested under the conditions presented in table 9 and table 10:

Table 9 Sample information of Setting B

Experiment date pH T (◦C) Turbidity (NTU)

2010/7/28~2010/8/6 7.25 20.2 106.2

2010/9/15~2010/9/16 7.49 18.7 46.5*

2010/9/20~2010/10/5 7.36 18.6 93.2

* The turbidity during 2010/9/15~9/16 was much lower than others was because the heavy rain duringthat week.

Table 10 Mixing conditions of Setting B

SettingRapidmixing

time(min)

Stirrervelocity 1

(rpm)

G-value1(s -1)

Slowmixing(min)

Stirrervelocity 2

(rpm)

G-value 2(s -1)

Settlingtime(min)

Rapid mixingvarious 2/5 200/300 400/700 3 30 24 15

Slow mixingvarious

2 200 400 5/10 30/50 24/50 15

5 200 400 1/3/5/10 30 24 15

4.2.3 Polymer dosage



Figure 9 Turbidity for flocculants under various rapid mixing conditions

It can be seen from Figure 9 that the turbidity removal under 5 mins rapid mixing was slightlybetter than 2 mins rapid mixing for each candidate. It is mainly because the polymer neededto be completely mixed with the sample.



Figure 10 Performance of 4 flocculants under various rapid mixing conditions

Slow mixing

Figure 11 shows the results of the experimental runs for 4 flocculants in terms of dosageunder varying slow mixing conditions.



Figure 12 Performance of 4 flocculants under 5mins/200rpm rapid mixing andvarious slow mixing

Comparing with the results of varying slow mixing condition test, the turbidity removal ofeach polymer was influenced by the change of slow mixing conditions. There was no uniform



Figure 13 Turbidity removals for Nalco 71403 under various mixing conditions



Figure 15 Turbidity removals for 77135+ An/Nonionic flocculants under variousmixing conditions (50ppm+5ppm)

For the rapid mixing, the turbidity removal under 5/200,5/30 was much better than2/300,5/30 for all the combinations. It indicated that under the same slow mixng, the rapidmixing did influence the performance of these combinations. 5mins rapid mixing is betterthan those under 2mins. Since the abnormal performance of polymer on Aug. 6 th (2/300,5/50;5/200,5/50; 5/300,5/50), the conclution (5mins rapid mixing is better than 2mins) conductedfrom Figure 13 is adopted.



Under mixing condition 5/200, 3/30, 3 anionic combinations and 4 cationic combinationscould achieved good turbidity removal (above 80%). The best combination was 77135+7757with a turbidity removal of 87%.

Under 5/300, 5/50 mixing condition, 77135+71406 and 77135+71413 removed turbidity upto 93% and 94% while the best anionic combination (77135+7757) removed 86% turbidity.

Coagulant Nalco 77135

From Figure 16, it can be seen that using coagulant only also remove turbidity above 80%under 5/300, 5/50 mixing condition. However, the flocs formed by coagulant alone weresmaller and looser than the flocs formed by the combination. So these flocs needed more

time to be settled.

4.2.6 Conclusion

1. Optimal mixing condition

For Nalco 71403, 5/200 rapid mixing, 5/30 slow mixing was the best mixing condition forNalco 71403.

The turbidity removal for CORE SHELL 71305 under 5mins rapid mixing is better than thoseunder 2mins. 5/200 rapid mixing, 3/30 slow mixing was the optimal mixing condition forCORE SHELL 71305.

For all the combinations, 5mins rapid mixing is better than those under 2mins. Under mixingcondition 5/200, 3/30, anionic combinations could achieved good turbidity removal (above80%). The best combination was 77135+7757 with a turbidity removal of 87%. Under mixingcondition 5/300, 5/50, cationic combinations removed turbidity up to 94%.

Only dosing 50ppm of coagulant could also remove turbidity above 80% under 5/300, 5/50



dosage. So new screen tests of coagulant were needed at the lower dosage. The new lowerdosage combinations were tested when the best lower dosage coagulant was selected.


The candidates were tested under the condition presented in table 11 and 12:

Table 11 Sample information of Setting C

Setting Experiment date PH T (◦C) Turbidity (NTU)

For flocculants 2010/11/08~2010/11/10 7.69 15.5 65.9*

For combinations 2010/11/17~2010/11/30 7.66 15.3 75.1*

* The turbidity much lower than Setting A was because the rain during that experiment days.

Table 12 Mixing conditions of Setting C

SettingRapidmixing

time(min)

Stirrervelocity 1

(rpm)

G-value1(s -1)

Slowmixing(min)

Stirrervelocity 2

(rpm)

G-value2 (s -1)

Settlingtime

(min)

Nalco 71403 5 200 400 5 30 24 15

CORE SHELL71305 5 200 400 3 30 24 15

AnionicCombinations 5 200 400 5 30 24 20

Cationiccombinations 5 300 700 5 50 50 20



Figure 17 Turbidity, Ptot and PO 4-P removals by Nalco 71403



Figure 19 Turbidity for 77135 combinations under lower dosage



It is clearly shown that cationic combinations performed better than anionic combinations onturbidity removal. The more coagulant dosing, the better performance. However, for anioniccombinations, flocculant dosage at 2ppm didn‘t improve turbidity removal comparing with1ppm dosage even 0.5ppm dosage.

For anionic combinations, 8190+7757 performed better than 8190+71605. The 8190+7757dosing combination of 15ppm+0.5ppm and 20ppm+0.5ppm were the best with the turbidityremoval efficiency of 72% and 74%.

For cationic combinations, 8190+71403 performed slightly better than 8190+71406 accordingto the turbidity removal comparing with the initial value(although the absolute turbidityvalues of 8190+71406 were lower). The 8190+71413 dosing combination at 15ppm+0.5ppmcould result in good turbidity removal (77%) while the best and the most dosing20ppm+2ppm could remove turbidity 83%.

Based on the result in Figure 21, 8190+7757 and 8190+71413 became the final anionic andcationic combination. The other two tests were performed to see the Turbidity, Ptot and PO 4-P concentration removal by these two combinations. The results are shown in Figure 22 and23.



4.3.6 Conclusion

1. Candidate for the further study

According to the turbidity removal, 71403 and 71305 were decieded as the 2 final flocculantcandidates and 8190+7757(anionic combination) and 8190+71413(cationic combination)were selected as the 2 lower dosage combinations for the PH varing test and Mechanism test.

2. Turbidity and phosphorous removal

The flocculants could remove 80%~90% turbidity while the lower dosage combinations couldremove 70%~80% turbidity during the experiments.

For the phosphorous removal, the flocculants and anionic combination could achieve around20% removal efficiency. The cationic combination only could achieve around 10% removalefficiency.

3. Optimal dosage for each candidate

The turbidity removal was still the main parameter to decide the optimal dosage for eachcondidate. Meanwhile, the lower dosing principle was also taken into account.

For the dosage of flocculants 71304 and 71503, 20ppm would obtain the best turbidityremoval among the dosing range of 0.5ppm~25ppm. But considering performance togetherwith sustainable and cost reason, 12.5ppm dosage was good for both flocculants. So12.5ppm was determined as the optimal dosage for flocculants.

For anionic/cationic combinations, 15ppm+0.5ppm was determined as the optimal dosage.Thus, the optimal dosage for each candidate was present in Table 13.

Table 13 Optimal dosage and the performance for each candidate



Table 14 Sample information of Setting D

Experiment date pH T (◦C) Turbidity (NTU)

2010/12/2 7.65 14.0 109.7

Table 15 Mixing conditions of Setting D

SettingRapidmixing

time(min)

Stirrervelocity 1

(rpm)

G-value1(s -1)

Slowmixing(min)

Stirrervelocity 2

(rpm)

G-value2 (s -1)

Settlingtime

(min)

71403/71305 5 200 400 3 30 24 20

Lower dosagecombinations 5 300 700 5 50 50 20

4.4.3 Polymer dosage

For the flocculants, the dosage of Nalco71403, CORE SHELL 71305 was 20ppm.

For the combination dosing, the Nalco 8190 dosage was from 15ppm while the flocculantdosage was 0.5.

The concentration of polymer stock solutions during flocculant and lower dosagecombinations test were both 0.45%.

4.4.4 Sample analysis

The supernatant was analyzed for Turbidity, pH and temperature immediately after the jar



Figure 24 The result of pH various test for flocculants



5. Removal Mechanism Experimental Results

5.1 GeneralMechanism tests aimed to understand the adsorption mechanism for three pharmaceuticalremoval possibilities by polymers.

- Adsorption onto particles and dissolved organic matters (with raw wastewater)

- Attachment onto dissolved organic matters (with filtered wastewater)

- Adsorption onto polymers (with tap water)

4 polymer candidates (flocculant 71403 and 71305, anionic combination 8190+7757, cationiccombination 8190+71413) were tested in 3 types of matrices (Tap water, 0.45μm filteredwastewater and raw wastewater).

All the samples were taken in duplicate for higher accuracy.

5.2 Testing conditionsThe experiments were performed under the conditions presented in table 16 and 17:

Table 16 Sample information of mechanism tests

Setting Experimentdate pH Turbidity

(NTU)DOC

(mg/l)Ptot

(mg/l)PO4-P(mg/l)

Tap water

2011/6/3

8.45 0.039 3.35 0.039 0.028

Filtered wastewater 7.58 28.0 52.66 6.90 6.36



5.4 Polymer dosage

The dosage of polymers were obtained from Setting C. For the flocculants, the dosage ofNalco71403 and CORE SHELL 71305 in Setting E was 12.5ppm. The concentration of polymerstock solution was 0.45%. For the combination dosing, the coagulant dosage was 15ppmwhile the flocculant dosage was 0.5ppm. The concentration of 7757 and 71413 stock solutionwas 0.45% while the concentration of coagulant 8190 stock solution was 1.8%.

5.5 Sample analysisThe supernatant water was analyzed for concentration of pharmaceuticals, Turbidity, DOC,PO4-P, P-total, pH immediately after the jar tests.

5.6 ResultsDissolved organic carbon (DOC)

DOC concentration during the mechanism tests are presented in Figure 26.



The turbidity values increased a little after dosing the polymers into tap water. It wasbecause in the tap water, there was nearly no compounds for flocs formation.

In the filtered wastewater sample, the turbidity increased from 25 NTU to 50 NTU. Althoughthe 0.45μm filter removed most of the particles in the raw wastewater, there were somecolloidal particles left in the sample. Destabilization occurred when dosing polymer. Thehigher increasing turbidity by combinations than flocculants indicated thatcoagulant+flocculant combinations could form more flocs from fine colloidal particles thanflocculants in suspended solids free wastewater.

In the raw wastewater, the turbidity removal was effective by both flocculants (65% removals)and combinations (70% removals). Settling for 0.5 h (jar test with no polymer) can alsoremove 40% turbidity. Among 4 candidates, anionic combination performed slightly betterthan others, but the differences were not evident.

Phosphorous

The Ptot and PO 4-P concentrations during the experiments were shown in Figure 28.

Figure 28 Ptot concentration for 4 polymers in mechanism tests



Table 19 Measuring concentration of 15 compounds in pharmaceutical working solution

NO. Compounds Measuring concentration in

working solution (mg/l)

Calculated dosing concentration

in sample(ng/l)1 atenolol 39.26 218122 bezafibrate 33.98 188773 carbamazepine 32.21 178964 clofibric acid 34.73 192945 diclofenac 32.73 18185

6 gemfibrozil 44.41 246697 Ibuprofen 50.24 27913

8 ketoprofen 32.1 178319 metformin 70.14 38966

10 metoprolol 38.48 21380

11 naproxen 25.43 1412712 paracetamol 36.99 2055213 propranolol 230.59 12810714 sulfamethoxazole 45.61 2534115 trimethoprim 52.72 29288

The measured concentrations of most compounds in working solution were higher than theexpected value (27mg/l). Because the expected concentration in working solution (27mg/l)was much higher than the maximum detection limit (1ug/l), the working solution sampleshould be diluted thousand times. That might result in less reliability of the sample analysis.

Moreover, the difference of concentration between non spiking sample and spiking samplesfor most compounds was 15000ng/l~30000ng/l. It indicated too high concentration inworking solution such as propranolol was due to analysis error.







Figure 31 Relation between average pharmaceuticals removal aftercoagulation/flocculation and logK ow , MW, Polarizability and logD pH7.4 in raw

wastewater



25~50 NTU turbidity increase (a bit better than tap water), no DOC removal andphosphorous removal.

In raw wastewater, larger and settleable flocs were formed which resulted in 65%~70%turbidity removal, 12%~17% Ptot removal, 6%~13% PO 4-P removal and no DOCremoval after coagulation/flocculation. The results indicate that polymers worked well onparticle removal and phosphorous removals were mainly along with particle removal.

The higher turbidity increase by combinations in suspended solids free water indicatesthat coagulant+flocculant combinations can form flocs from dissolved matters to solidphase.



6. Conclusions and Recommendations

6.1 ConclusionsThis thesis study aimed to investigate the application of organic polymers ascoagulants/flocculants to remove the organic micro-pollutants and phosphorous from rawwaste water.

During the proposed study an inventory was made of the experiences with different polymerswith respect to the removal of organic micro pollutants and phosphate.

Different polymers were selected and jar tests were performed, testing the different polymersunder different conditions: mixing condition, dose, pH.

2 cationic polymer flocculants (Nalco 71403 and CORE SHELL 71305) and 2 lowerdosage coagulant+flocculant combinations (1 anionic combination 8190+7757 and 1cationic combination 8190+71413) were selected from 5 coagulants and 10 flocculantsaccording to turbidity (suspended solids) removal. These 4 candidates were tested tofind the removal mechanism of organic micro-pollutants in waste water.

The various mixing conditions for coagulation/flocculation didn‘t affect on the turbidityremoval by polymers that much.

The relatively optimal mixing conditions for 4 candidates were:

SettingRapidmixing

time(min)

Stirrervelocity 1

(rpm)

G-value1(s -1)

Slowmixing(min)

Stirrervelocity 2

(rpm)

G-value2 (s -1)

Settlingtime

(min)

Nalco 71403 5 200 400 5 30 24 20



Organic micro-pollutants removal mechanisms by coagulation/flocculation

It can be concluded that under current conditions polymer do not contribute significantly

to remove the pharmaceuticals in both tap water and wastewater.

Despite the much better turbidity removal in raw wastewater than filtered wastewater,there is no significant pharmaceutical removal in both matrices. This fact indicated thatpharmaceuticals might adsorp on even very fine particles or organic matters that couldnot be removed by coagulation/flocculation under current polymer dosage and mixingconditions.

Turbidity, DOC and Ptot removal

In tap water matrix, coagulation/flocculation with polymers could give rise to theformation of only a few and very fine flocs. It resulted in a little turbidity increasing.

In suspended solid free waste water (0.45μm filtered wastewater),coagulation/flocculation could result in the formation of fine flocs as well. There were25~50 NTU turbidity increase (a bit better than tap water), no DOC removal andphosphorous removal.

In raw wastewater, larger and settleable flocs were formed which resulted in 65%~70%turbidity removal, 12%~17% Ptot removal, 6%~13% PO 4-P removal and no DOCremoval after coagulation/flocculation. The results indicate that polymers worked well onparticle removal and phosphorous removals were mainly along with particle removal.

The higher turbidity increase by combinations in suspended solids free water indicatesthat coagulant+flocculant combinations can form flocs from dissolved matters to solidphase.

The performance of organic polymers



sufficient contact time that the micro-pollutants need longer time (more than one hour) toattach onto particles.

If good relationship can be found between particles removal and micro-pollutants removal inraw wastewater by applying longer contact time or higher dosage, the turbidity removal couldbe used to select the polymers. If not, the selection principle of polymers still needs to beworked out.

Preparation concentration in polymer stock solution

In Setting A screening test and Setting B optimal mixing condition test, the concentration inpolymer stock solution exceeded the recommended stock solution preparation concentration.

It was due to misunderstanding of the polymer information on the Material Safety DataSheets.

For Setting C, D and E, the preparation concentrations were corrected to the right values.Comparing the turbidity removal in 5 settings, it seems that the high preparationconcentration don‘t affect on the polymer performance that much.

Samples preparation

During the elaboration of experimental results, the trickiest part was the calibration of sampleresults. Since the reliability of analytical results much depends on the sample matrices, thesample preparation procedures were discussed to improve the reliability of pharmaceuticalanalytical results.

- To prevent the contamination on the samples, prewash all the materials such ascontainers, tubes, etc. with demi water.

- For wastewater matrices, take 10ml sample instead of 100ml to minimize the matrixeffects.



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52

Appendices

Measured concentration of 15 organic micro-pollutants (ng/l)

TAP WATER FILTERED WASTE WATER RAW WASTE WATERSample name 1 2 Average Sample name 1 2 Average Sample name 1 2 Average

Atenolol

T_Non_Spiking 347 347 347 F_Non_Spiking 5343 5920 5631 R_Non_Spiking 3661 4710 4186

T_Spiking 10253 16380 13317 F_Spiking 24595 22448 23521 R_Spiking 18510 21084 19797

T_71403 17244 11881 14562 F_71403 7207 23410 15308 R_no polymer 20919 20640 20780

T_71305 10261 20156 15209 F_71305 24539 24738 24639 R_71403 21703 21924 21813

T_8190+7757 19869 26647 23258 F_8190+7757 25081 22104 23593 R_71305 21297 21274 21285

T_8190+71413 11845 30953 21399 F_8190+71413 24557 18440 21498 R_8190+7757 18532 20822 19677

R_8190+71413 20345 24192 22269

Bezafibrate

T_Non_Spiking 0 0 0 F_Non_Spiking 179 325 252 R_Non_Spiking 220 528 374T_Spiking 17245 16242 16743 F_Spiking 15421 18032 16727 R_Spiking 18360 20195 19277

T_71403 15690 15443 15567 F_71403 16952 17771 17362 R_no polymer 19975 20123 20049

T_71305 16230 14940 15585 F_71305 17721 20400 19060 R_71403 19199 19045 19122

T_8190+7757 14553 14625 14589 F_8190+7757 17612 18230 17921 R_71305 18627 19002 18815

T_8190+71413 15092 14540 14816 F_8190+71413 19657 18765 19211 R_8190+7757 18767 19300 19033

R_8190+71413 20142 18421 19281

Carbamazepine



T_71403 16260 9649 12954 F_71403 21237 19810 20523 R_no polymer 19512 20335 19924

T_71305 9518 15733 12625 F_71305 21728 20788 21258 R_71403 21352 18962 20157T_8190+7757 18027 21493 19760 F_8190+7757 22582 19007 20795 R_71305 18878 18168 18523

T_8190+71413 11075 24860 17968 F_8190+71413 21583 18920 20252 R_8190+7757 16873 19159 18016

R_8190+71413 18706 19381 19043



53


Clofibric acid



T_71403 16181 17813 16997 F_71403 13572 22206 17889 R_no polymer 21891 20736 21314

T_71305 17663 16164 16914 F_71305 23885 28554 26220 R_71403 17742 19466 18604

T_8190+7757 8128 13964 11046 F_8190+7757 22183 21734 21958 R_71305 17343 16717 17030

T_8190+71413 8622 14272 11447 F_8190+71413 22392 20567 21479 R_8190+7757 23054 17793 20423

R_8190+71413 18228 18314 18271

Diclofenac



T_71403 18141 27238 22690 F_71403 21370 20417 20893 R_no polymer 19330 11219 15275

T_71305 27384 28423 27904 F_71305 17794 14049 15921 R_71403 12037 20391 16214

T_8190+7757 19922 22637 21279 F_8190+7757 12823 21011 16917 R_71305 22218 25513 23865

T_8190+71413 22864 11510 17187 F_8190+71413 21563 17899 19731 R_8190+7757 25624 14420 20022

R_8190+71413 22597 28595 25596

Gemfibrozil



T_71403 24369 22092 23230 F_71403 25969 27836 26903 R_no polymer 34323 32553 33438

T_71305 25028 25598 25313 F_71305 28580 30438 29509 R_71403 36094 31789 33941

T_8190+7757 23030 23915 23473 F_8190+7757 32034 27647 29840 R_71305 28289 28826 28558

T_8190+71413 21942 22349 22145 F_8190+71413 30865 31968 31416 R_8190+7757 32659 28733 30696

R_8190+71413 30613 32451 31532

Ibuprofen *T_Non_Spiking 0 0 0 F_Non_Spiking 19477 12826 16151 R_Non_Spiking 15403 12303 13853


T_71403 18982 16132 17557 F_71403 29121 31286 30204 R_no polymer 22189 31413 26801



54


T_71305 14494 28778 21636 F_71305 22450 34263 28356 R_71403 31903 22647 27275

T_8190+7757 17889 18285 18087 F_8190+7757 31254 33974 32614 R_71305 33849 17435 25642

T_8190+71413 24354 19525 21939 F_8190+71413 33523 44066 38795 R_8190+7757 23151 29452 26302

R_8190+71413 28721 29230 28976

Ketoprofen



T_71403 15923 16326 16125 F_71403 13589 14022 13805 R_no polymer 15356 12918 14137

T_71305 13460 16755 15107 F_71305 13960 15735 14847 R_71403 15514 18804 17159

T_8190+7757 15087 16346 15716 F_8190+7757 14643 14890 14767 R_71305 14719 18170 16444

T_8190+71413 13419 17205 15312 F_8190+71413 16058 14716 15387 R_8190+7757 18375 18592 18484

R_8190+71413 15688 18221 16954

Metformin



T_71403 19218 18681 18949 F_71403 14652 22537 18595 R_no polymer 19327 19653 19490

T_71305 21240 17996 19618 F_71305 19295 21521 20408 R_71403 23976 25440 24708

T_8190+7757 16948 17484 17216 F_8190+7757 21538 22208 21873 R_71305 23333 24497 23915

T_8190+71413 17518 23050 20284 F_8190+71413 21284 19256 20270 R_8190+7757 25260 24931 25095

R_8190+71413 23129 20306 21718

Metoprolol



T_71403 16795 11868 14332 F_71403 7365 22545 14955 R_no polymer 20490 20113 20302

T_71305 10029 19162 14596 F_71305 23622 24186 23904 R_71403 21404 21123 21264

T_8190+7757 18328 26298 22313 F_8190+7757 24012 21462 22737 R_71305 21152 20650 20901

T_8190+71413 11492 30465 20978 F_8190+71413 24846 17611 21228 R_8190+7757 17836 20587 19211

R_8190+71413 20548 24657 22602

Naproxen T_Non_Spiking 162 190 176 F_Non_Spiking 4694 4789 4741 R_Non_Spiking 4619 4647 4633



55



T_71403 14220 14770 14495 F_71403 13565 18939 16252 R_no polymer 19868 20405 20136

T_71305 14696 14877 14786 F_71305 13922 20717 17319 R_71403 20550 20733 20642

T_8190+7757 11479 14520 13000 F_8190+7757 15267 19993 17630 R_71305 19149 18507 18828

T_8190+71413 11546 14694 13120 F_8190+71413 16281 18604 17442 R_8190+7757 19320 18785 19053

R_8190+71413 20000 19758 19879

Paracetamol *



T_71403 16744 12371 14557 F_71403 35436 33678 34557 R_no polymer 38478 50268 44373

T_71305 9724 20043 14884 F_71305 34336 34264 34300 R_71403 19928 16129 18029

T_8190+7757 18676 28893 23784 F_8190+7757 36896 35706 36301 R_71305 17831 20875 19353

T_8190+71413 11864 33401 22632 F_8190+71413 39118 42071 40594 R_8190+7757 29994 13784 21889

R_8190+71413 35791 395150 215470

Propranolol *



T_71403 104334 72956 88645 F_71403 118915 155954 137435 R_no polymer 66929 74241 70585

T_71305 72093 102234 87164 F_71305 163235 134036 148636 R_71403 88597 70640 79618

T_8190+7757 138886 162339 150613 F_8190+7757 152317 73967 113142 R_71305 68292 62320 65306

T_8190+71413 84703 178761 131732 F_8190+71413 122125 68339 95232 R_8190+7757 53347 71618 62483

R_8190+71413 61101 130587 95844

Sulfamethoxazole



T_71403 18832 18261 18547 F_71403 13921 15752 14837 R_no polymer 17094 17877 17486T_71305 19642 18031 18836 F_71305 15068 18093 16580 R_71403 16682 17513 17098

T_8190+7757 17551 17858 17705 F_8190+7757 16426 16399 16413 R_71305 16302 17260 16781

T_8190+71413 18209 18074 18141 F_8190+71413 17617 16071 16844 R_8190+7757 16806 17874 17340




R_8190+71413 17842 17860 17851

Trimethoprim *



T_71403 25654 17552 21603 F_71403 7297 30619 18958 R_no polymer 24155 24454 24304

T_71305 15132 29444 22288 F_71305 32344 32689 32517 R_71403 27482 26874 27178

T_8190+7757 29963 39459 34711 F_8190+7757 34138 29806 31972 R_71305 25910 26175 26043

T_8190+71413 18057 45184 31620 F_8190+71413 33970 23399 28684 R_8190+7757 27975 26359 27167

R_8190+71413 25403 33492 29447

*: Less reliable results of these compounds

Msc Thesis about water

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