Optimization of Ozonation for CT Compliance by HC121004055119

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									Impact of Nanomaterials During Wastewater
               Treatment


           Ganesh Rajagopalan
        Kennedy/Jenks Consultants
               Irvine, CA

                (949) 261 1577
          rganesh@kennedyjenks.com

      Pacific Northwest Pretreatment
                Conference
            10 September 2008
                            Kennedy/Jenks Consultants
    Nanotechnology is Here to Stay

• Predicted market size > $1 trillion /
  Year by 2015

• Approach “Information Technology
  + Telecom”




                           Kennedy/Jenks Consultants
Nanotechnology & Health Effects




                    Kennedy/Jenks Consultants
                   Outline
• What are Nanomaterials

• Why Should We Care?

• Where Do/Will They Come into
  Wastewater from?

• Nanoscale Materials in Treatment
  Processes

• Summary

                           Kennedy/Jenks Consultants
          Nanotechnology Definition

• An emerging field that

  • creates and uses nanoscale material
    where the particle size is in the range
    of 1 to 100 nanometers (nm) in at least
    one dimension.

  • facilitates materials manipulation at the
    molecular level.
              National Nanotechnology Initiative
                               Kennedy/Jenks Consultants
           Nano =               10-9    meters




 Buckminster Fullerene – C60     Single Wall Carbon Nanotube
“Buckyball” – 0.7 nm diameter
                                            Kennedy/Jenks Consultants
                  Relative Size




     Human Hair            Red Blood Cell
D = 50,000 Nanometers   D = 7,000 Nanometers

                              Kennedy/Jenks Consultants
   So What if the Particles are Small?

• High surface area
   > 2 orders of µm particles


• High reactivity
   High electron density


• Properties change at the nanoscale

                            Kennedy/Jenks Consultants
Relative Size




         Kennedy/Jenks Consultants
            Properties Change at Nanoscale

•   Thermal characteristics

•   Diffusion characteristics

•   Reactivity (e.g Gold)

•   Electronic properties

•   Optical properties (e.g. Gold, Carbon)

                                Kennedy/Jenks Consultants
Gold Nanoparticles: 30 – 150 nm




                  Kennedy/Jenks Consultants
         When Released into Wastewater

• Different Characteristics in Products

 Different Fate & Transport in
 WWTP

• Existing Model Predictions May Not
  Be Valid


                          Kennedy/Jenks Consultants
                  Technology Development
                          Cycles

Nanotechnology Currently in Yellow Zone

                                            Manufacturing

                       Pilot
                      2- 5 years
Dollars




           R&D
          20+ years


                                   ← Current market condition



                               Time in Years
                                                       Kennedy/Jenks Consultants
Potential Sources in WWTP

   (Products Containing
     Nanomaterials)



                  Kennedy/Jenks Consultants
Nanotechnology Products




                Kennedy/Jenks Consultants
         Emerging Contaminants
                             PhACs – Pharmaceutically
                             Active Compounds
      EDCs – Endocrine
      Disrupting Compounds




Industrial Chemicals
                                    Nanomaterials


                               PCPs – Personal
                               Care Products

                                  Kennedy/Jenks Consultants
Personal Care Products




                Kennedy/Jenks Consultants
      Market Information

• Over 75 Products in Market

• > 60% Products to Incorporate
  Nano

• 9500 Products Can Potentially
  Use Nano Substitutes

• > 50 Different Nanomaterials
                        Kennedy/Jenks Consultants
        Some Products and Nanomaterials
        Product             Nano Ingredients
Sunscreens            TiO2, ZnO2, SiO2 Nano-
                        Encapsulations
Anti-Aging Products   Lyphazome Nanospheres,
                        Vitamin E
Eye Liners            Fullerenes
Hair Spray /          Nano Silver
  Conditioners
Anti-Rash Creams      Nano ZnO
Soaps                 Germanium
Tooth Paste           Gold, Hydroxyapatite
                                    Kennedy/Jenks Consultants
Agriculture, Pesticides and
         Biocides




                    Kennedy/Jenks Consultants
      Materials and Market

• Nano Silver, Gold & Copper



• Nano Silver is Among the Most
  Used
  • 67 of 381 Listed by Wilson Center




                           Kennedy/Jenks Consultants
              Products
• Bactericides/Fungicides

• Band-Aids

• Air Fresheners

• Washing Machines

• Socks & Shoe liners
                         Kennedy/Jenks Consultants
           Nano Silver Issues
• Nano Ag Significantly More Effective

• Different Mechanisms Proposed

• Swedish Wastewater Utilities Predict 2 - 3
  Fold Ag Increase in Wastewater

• Possible Biomass Inhibition and Resistant
  Strain Development

• First Nanomaterial to be Regulated by
  USEPA
                              Kennedy/Jenks Consultants
Kennedy/Jenks Consultants
Cartoon from ETC Group Report   Kennedy/Jenks Consultants
Food and Supplements




               Kennedy/Jenks Consultants
Cartoon from ETC Group Report   Kennedy/Jenks Consultants
Nano in Automobiles




            Kennedy/Jenks Consultants
      Some Other Products
• Medical Industry
  • Diagnostic / Drug Delivery

• Semiconductor
  • CMP

• Paints and Coatings
  • Nano Cerium and Metal Oxides

• Batteries
  • Nano LiCo, Ni


                                 Kennedy/Jenks Consultants
Nanoparticles in Wastewater
   Treatment Processes




                  Kennedy/Jenks Consultants
               Potential Issues

• How will nanomaterials Affect
  Existing Treatment Processes?




• Can nanomaterials be removed in
  Treatment Plants?

                         Kennedy/Jenks Consultants
            Contaminants in Wastewater




A. Suspended Particles.      B. Dissolved Chemicals.
Treatability predominantly   Treatability predominantly
controlled by physical       controlled by chemical
characteristics              characteristics
> 1 m.




                                          Kennedy/Jenks Consultants
                   Background

• Particle Size Distribution is a Continuum
  % Distribution




                          1 m
                     Particle Size



                                     Kennedy/Jenks Consultants
         Contaminants in Wastewater - Revised




A. Suspended Particles.   B. Nanoscale Particles.    C. Dissolved
Treatability              Treatability not well      Chemicals. Treatability
predominantly             understood. Likely to      predominantly
controlled by physical    combine & differ from,     controlled by chemical
characteristics           A & C.                     characteristics




                                                    Kennedy/Jenks Consultants
 Monitoring Nanomaterials in WWTP

• Differentiate Conventional and
  Nanomaterials

• Nanomaterials Elusion in GC/MS

• Sample Prep

• Nanoparticles Counter
  • Coulter Counter
  • Malvern Zetasizer

                            Kennedy/Jenks Consultants
Biogenic Nanoparticle Distribution in
        Secondary Effluent




                        Kennedy/Jenks Consultants
                                          “Calibration” of Biogenic Nanoparticles in
                                                      Secondary Effluent

                                100

                                 90
Average Particle Count (kCPS)




                                 80

                                 70

                                 60

                                 50                                     y = 0.6829x + 17.611
                                 40                                          R2 = 0.9903

                                 30

                                 20

                                 10

                                  0
                                      0       20      40        60        80         100       120
                                              % Secondary Treated WW (0.2 u Filtrate)


                                                                         Kennedy/Jenks Consultants
  Primary Settling: With & Without Coagulant


• Poor settling without coagulant

• Biogenic Organics
   • No Systematic Data for < 500 nm

• Removal of 100 nm Humic Substance
  Correlated Well with Charge Density of
  Polymer

• Particle Size Impacts pHzpc of Titania
   • 3.6 nm : pHzpc 4.8
   • 8.1 nm : pHzpc 6.2


                                       Kennedy/Jenks Consultants
 Primary Settling – With & Without
            Coagulant

• Aggregation of Mfgd Nanomaterials
  • Deviated from Micron & Nanocolloidal
    Particles
  • Highly Mobile near PZC
  • More Aggregation farther away
  • Likely to Impact Coagulation


• Metal Oxide (@ 10 mg/l) Nanoparticles
  • ~ 60 % Removed by Coagulation
  • Additional 20% by Filtration



                              Kennedy/Jenks Consultants
  Primary Settling – With & Without
             Coagulant

• Nanomaterials Complex with NOM

• Functionalization May Limit Collision of
  Nanomaterials




                             Kennedy/Jenks Consultants
            Activated Sludge
• No systematic study to date

• 10% Removal of Nano Latex Beads in
  Biofilms

• C60 (0.4-4 mg/l) Inhibited (Soil) Nitrate
  Reducers
• Lots of unknowns
  •   Attached to microbial flocs?
  •   Transported across cell membranes?
  •   Adsorb dissolved metals
  •   +/- on activated sludge performance?
                                  Kennedy/Jenks Consultants
        Granular Filtration

• µm particles removed mainly by
  Interception, Sedimentation

• Brownian diffusion likely to
  dictate nanoparticle behavior

• Functionalization will Lower
  Retention
                         Kennedy/Jenks Consultants
          Granular Filtration
• Few data for 1-100 nm particles

• Tortuosity of Flow Path More
  Significant Than Porosity
• 10 – 50% removal of 46 – 825 nm
• Low <1 µm particles removal with
  • Increase of Filter media size
  • Filter ripening

                            Kennedy/Jenks Consultants
            Membrane Filtration
• Theoretical Prediction
   • Critical Size for Fouling ~100 nm

• Variation with Membranes & Nanomaterials

• OCWD MF Studies
   • Max Flux Reduction by 200 to 3.5 nm


• WWTP Effluent in UF
   • 100 to 200 nm fraction Caused Max Fouling

• Cellulose Acetate Membrane & Nano Latex
  Beads
   • Influx Point at 500 nm

                                         Kennedy/Jenks Consultants
       Nano Silica in MF/UF

• Smaller Particles had Higher
  Porosity
  • 60 nm : 0.32 – 0.38
  • 34 nm : 0.35 – 0.43


• Cake Porosity High in MF

• Rate of Flux Drop High in MF

                          Kennedy/Jenks Consultants
        Other Treatment Processes
• Electrocoagulation
  • Mostly Used in Semiconductor Industry
  • Appear to be effective for 200 nm particles


• Ion Exchange
  • Used during Nanomaterials Synthesis
  • Not Studied during Wastewater Treatment


• Disinfection
  • Not Evaluated

                                  Kennedy/Jenks Consultants
         Regulatory Status
• TSCA
  • Existing Vs “New”
  • Nanomaterials as “Significant New Use”??

• CWA
  • Can Potentially set NPDES, WQ Stds

• SDWA
  • Can Set MCLs, MCLGs, BAT based limits


• Nano silver regulated by FIFRA

                               Kennedy/Jenks Consultants
            Summary

• There’s Plenty of Room at the
  Bottom - Richard Feynman (12-29-
  1959) @ Caltech



• Applies to Nano in Wastewater Also




                        Kennedy/Jenks Consultants
                        WEF TPU
New! Nanoparticles (May 2008) (Members) (Nonmembers)

This Water Environment Federation (WEF) Technical Practice
  Update (TPU) provides one of the first overviews of the potential
  effects of manufactured nanomaterials in wastewater treatment
  plants. Nanotechnology refers to the emerging field that creates
  and uses nanoscale material (manufactured nanomaterial) where
  the particle size is in the range of 1 to 100 nanometers (nm) in at
  least one dimension. Nanotechnology facilitates manipulation of
  materials at the molecular level. Because of their extremely
  small size and their ability to be manipulated at the molecular
  level, nanomaterials exhibit novel properties and functions that
  differ from their conventional counterparts, such as micron
  suspended or dissolved materials (National Nanotechnology
  Initiative, 2007).


http://www.wef.org/ScienceTechnologyResources/TPUs/

                                             Kennedy/Jenks Consultants
       WEF TPU Co-Authors
• Background            : April Gu

• Relevance to WW       : Kathleen Sellers

• What do We Know?
  • Potential Sources   : Ganesh Rajagopalan
  • Analyses             : Dermont
    Bouchard
  • Treatability         : Ganesh
    Rajagopalan
  • Regulatory Status   : Igor Linkov

• Where are We Going?     Kennedy/Jenks Consultants
Questions?




         Kennedy/Jenks Consultants

								
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