OBG PRESENTS:

Webinar: Treating Emerging Contaminants – Both Conventional and Advanced Treatment TechnologiesScott A. Grieco, PhD, PE June 21, 2016

AGENDAEmerging Contaminants Categories

Environmental Detections

EC Regulations

Biological Treatment

Physical/Chemical Treatment

Q/A?

What Are Emerging Contaminants?

▪ Compounds

▪ Pharmaceuticals

▪ Personal care products

▪ Antibiotics

▪ Sterols and hormones

▪ Endocrine disrupters

▪ Herbicides/pesticides

▪ Flame retardants

▪ Others

▪ Varying chemical properties

▪ Dissimilar structures and functional groups

▪ Molecular size

▪ Polarity

▪ Solubility

Health concerns regarding EC’s

▪ Many are classified as

▪ Potentially carcinogenic

▪ Impactful to the endocrine system & cellular development

▪ There still is a scarcity of data on human health and ecosystem effects:

▪ At environmental levels

▪ In multi-component mixture

▪ Chronic or generational effects

▪ Metabolites may be more persistent or toxic than parent compound

Sources of ECs

Ubiquitous Nature of ECs

Example studies

▪ Loos (2009) - Europe

▪ 122 river sampling stations

▪ 27 countries

▪ 35 compounds

▪ Kolpin (2002); Focazio (2008)

▪ 139 stream samples

▪ 74 public drinking water supplies

Status of EC regulations

▪ No existing Federal regulations

▪ There are non-enforceable Health Advisories for some compounds

▪ Contaminant Candidate Lists (CCL)

▪ Unregulated Contaminant Monitoring Rule (UCMR)

▪ FDA requires ecological testing of pharmaceuticals when environmental concentration exceeds 1 μg/L.

▪ Certain states have independent standards for specific compounds

▪ 147 compounds are likely to be environmentally persistent in the environment (Bolong, 2009)

How can we treat ECs ?

▪ Biological

▪ Physical/Chemical

Biological Treatment

0.1 10 1000 100000

17alpha-ethynylestradiol (EE2) testosterone

7 beta-estradiol (E2), 2,4 DCP, azithromycin, BHT, bupropion,

ciproflaxin, estrone (E1), fluoxetine, malathion, norfloxacin,

paracetamol, setralineATH(Traseolide), BHA, cimetidine, dehydronifedipine, diazepam,

dlitiazem, diphenhydramine, indolebutyric acid, lindane,

primidone, benzophenoneCarbaryl, chlorpyrifos, diazinon, diethylphthalate, estriol (E3),

fenofibrate, phenazone, propanolol, triclocarban, trimethoprim

Sulfamethoxazole, TCEP, Tetrachloroethene, venlaflaxin

Gemfibrozil, HHCB, iopromide, lincomycin, roxithromycin

4-methylphenol, 4-OP (mono,di) Eos, bis-2-ethylhexylhphthalate,

clofibric acid, fenobiric acid

AHTN, atenolol, bezfibrate, cholesterol, DEET, diclofenac,

erythromycin, Fluoranthene, ketoprofen, mefenamic acid,

metoprolol, naproxen, Pyrene, TDCPP, triclosan1,4 Dichlorobenzene, acetaminophen, atrazine, carbamazepine,

nonylphenol, phthalic anhydride

Bisphenol A, Ibuprofen, NonylPhenol, NPEOs, TBEP, TCPP

POTW EFFLUENTS

ng/L

Bisphenol A Effluent Concentration vs. Treatment SRT

0

500

1000

1500

2000

0 10 20 30 40 50

SRT

PPT

BP-A Data fromReference Papers

Biological WWTP

▪ Increasing Sludge Retention Time (SRT) can improve removal for some ECs

Biological Wastewater Treatment

▪ Biological processes can treat many of the identified ECs.

▪ Constraints to consider: Concentration; Configuration; System Operation

▪ Example ECs persistent through aerobic systems:

▪ carbamazepine, erythromycin, hydrochlorothiazide, indomethacine, metoprolol, and tris(2-chloroethyl) phosphate (TCEP), PFAAs

▪ Persistent ECs not effectively treated within mesophilic or thermophilic anaerobic systems

▪ Key issue for sludge digestion & biosolids disposal

▪ 30% solids = 70% water

Biological Wastewater Treatment

▪ Improve existing treatment

▪ Increase SRT

▪ Alternative technologies

▪ Membrane bioreactor (MBR)

▪ Enhanced Powered Activated Carbon Treatment (PACT)

▪ For the most persistent constituents additional treatment will likely be required.

▪ Many ECs still lack adequate study

MBR Technology

MBR plants are typically 1/3 to 1/4 the size of conventional activated sludge-type treatment plants

MBR produce significantly less sludge, operate at high MLSS & long SRT

MBR technology combines the functions of a clarifier and filter

MBR technology provides consistent solids free effluent

MBR Treatment

▪ Submerged Membranes

▪ Higher flows / Conventional WW

▪ GE Water – ZeeWeed

▪ Kubota – Flat sheet

▪ External Membranes

▪ Smaller flows / higher flux

▪ Berghof

▪ Pentair

Physical/Chemical Treatment

Adsorption

Adsorption vs. Absorption

▪ Adsorption is accumulation of molecules on a surface in contact with an air or water phase

▪ Absorption is dissolution of molecules within a phase (e.g., fume scrubber)

gas H aqP K c

ASSA

eL

eLe

ck

ckqq

1

max

Causes of Adsorption

▪ Dislike of Water Phase – ‘Hydrophobicity’

▪ Attraction to the Sorbent Surface

▪ van der Waals forces: physical attraction

▪ electrostatic forces (surface charge interaction)

▪ chemical forces (e.g., - and hydrogen bonding)

DIFFUSION

▪ Process where solute goes from regions of higher concentration to regions of lower concentration

▪ Fick’s Law:

▪ Predicts how diffusion causes the concentration to change with time

2

2

r

CD

dt

dCe

Boundary LayerTransport

Pore DiffusionJP = -DPc

Surface DiffusionJS = -DSq

Local Equilibriumq = q*(c)

Adsorbent

Activated Carbon

▪ Natural Material

▪ Bituminous coal

▪ Coconut shell

▪ Wood

▪ Heterogeneous

▪ Chemical differences (functional groups, metals)

▪ Pore sizes

Activated Carbon

Source: 2007 AWWARF Report (Snyder et. al.)

Synthetic Media

Base material: styrene-based copolymer

Made by controlled pyrolysis of bead (activation)

Technical advantages:

Manufactured “engineered” product

Improved pore distribution: Fast kinetics and high capacity

Pure organic – no ash

MaterialMicro-pores (<20A)

Meso-pores

(20 to 500A)

Macro-pores

(>500A)Total >20 / Tot

OptiporeL493

0.50 0.35 0.31 1.16 0.57

Ambersorb563

0.23 0.14 0.23 0.60 0.61

FiltrasorbF400

0.48 0.09 0.04 0.61 0.21

*Values in cc/g

Comparison to Carbon for 1,4-Dioxane

Source: Woodard, S., Remediation, 2014

System Configuration

Pre-filters / adsorption columns

Requires on-site regenerationSteam or caustic

Liquid residual product requires management / disposalSignificant volume reduction

Source: Woodard, S., Remediation, 2014

Adsorption Applicability

Design Factors

Contact time

Type of adsorbent (carbon type or synthetic)

Site Factors

Competitive adsorption / desorption

Inorganics

NOM

Site Specific Evaluation

Concentrations, Flows, Background water quality

Rapid Small-Scale Column Testing (RSSCT)

Small column, high-throughput testing

Simulate months / years full-scale operation in days timeframe

Scalable results to size full-scale system

Oxidation

Oxidizing reactions break chemical bonds and destroy

organic compounds

Complete Oxidation

Organic (C-H-O-N-S) + Oxidant CO2 + H20 + Salts

Incomplete Oxidation

Organic (C-H-O-N-S) + Oxidant Smaller Organics

Effectiveness based on:

Chemical structure

Electrochemistry (types / number of bonds)

Configuration of organic molecule

Relative power of oxidant

UV

Source: 2007 AWWARF Report (Snyder et. al.)

Ultraviolet (UV) / Ozone (O3)

Ultraviolet (UV) / Hydrogen Peroxide (H2O2)

Hydrogen Peroxide (H2O2) / Ozone (O3)

UV / Titanium dioxide (TiO2)

Advanced Oxidation:

Radical generation

Hydroxyl radical(OH)

HOOHOHOH h 32222

HOOHOOH 2322 2

HOOHOHO h

223 2

UV/H2O2 (Advanced Oxidation)

Source: 2007 AWWARF Report (Snyder et. al.)

ECs of Current Interest1,4-Dioxane

Perfluorinated Compounds

1,4-Dioxane

Historically, 90% of U.S. production used as stabilizer in chlorinated solvents, mainly 1,1,1-TCA (USEPA, 2015)

2-8% typical content in 1,1,1-TCA (Mohr, 2010)

Henderson et al., Integrated Env. Assessment & Management, 2012, Co-occurrence of 1,4-Dioxane with Trichloroethene

14Dx: Occurrence Not Just From Stabilizers

CONSUMER PRODUCTS

“During 1992-1997, the average concentration of 1,4-dioxane in some cosmetic products reportedly ranged from 14 to 79 mg/kg.

In a more recent survey reported by the Campaign for Safe Cosmetics, the levels of 1,4-dioxane in cosmetic products were found to be lower (1.5-12 ppm in baby and children's products and 2-23 ppm in adult products) than in the survey done by the FDA in the 1990s.”

Source: ATSDR

14Dx: Properties

Completely miscible in water

Octanol-water partitioning (Log Kow = -0.27)Highly hydrophilic

Henry’s Constant (4.8x10-6 atm-m3/mol)Low volatility

Single-bonded cyclical ether (C4H8O2)Requires high energy to oxidize chemical bonds

14Dx: Example Media-Specific Target Values

USEPA tap water screening level (1x10-6 ELCR) (USEPA, 2013)

USEPA regional screening level (RSL)

New Jersey groundwater quality standard

USEPA risk assessments (1x10-6 ELCR) (USEPA, IRIS, 2013)

Vermont health advisory

Massachusetts drinking water limit

New Hampshire public water supply reporting limit

0.67 μg/L

0.46 μg/L

0.40 μg/L

0.35 μg/L

0.30 μg/L

0.30 μg/L

0.25 μg/L

Example of 1,4-D Co-contaminant Site

3 month breakthrough

Competitive effects removed through lead bed

Benefit of combined technologies: AOP – GAC

Source: OBG

Advanced Oxidation Applications

Mountain View, CA

HiPOx technology

Operational since 2003

15 µg/L 1,4-Dx with > 10,000 µg/L DCE / TCE

Colorado

Purifics Photo-cat technology

700 gpm

TCE / DEC and 1,4-Dx co-contaminated site

Influent ~ 100 µg/L Effluent 0.3 µg/L 1,4-Dx (DW treatment goal)

PerfluorinatedCompounds

Stain resisting compounds (Scotchgard)

Non-stick cookware (Teflon manufacturing process)

Firefighting foams for airfields

Between 2000 and 2002, PFOS was voluntarily phased out of production in the U.S. by its primary manufacturer.

In 2006, 8 major companies voluntarily phased out global production of PFOA and PFOA-related chemicals.

There are a limited number of ongoing uses

Linked to developmental effects (e.g., low birth weight, accelerated puberty, skeletal variations), cancer, liver effects, immune effects (e.g., antibody production and immunity), and thyroid effects.

Source: EPA PFOA/PFOS Fact sheet, 2016

Perfluoroalkyl Acids (PFAAs)

Perfluorocarboxylic Acids (PFCA)

Perfluorosulfonic Acids (PFSA)

e.g., Perfluorooctanoic acid (PFOA)

e.g., Perfluorooctane sulfonate (PFOS)

• Short Chain vs Long Chain (> 7, 8 C)• Affects treatment, fate

Perfluorobutanoic acid (PFBA): 4 monthsPFOA/PFOS: 8.8/5.4 years

Source: Dudley, L., Masters Thesis, 2012

▪ On May 19th, 2016 USEPA released its final HA for PFOA & PFOS

▪ HAs are not enforceable and non-regulatory.

EPA Health Advisory

PFAA Drinking Water Health Advisory

PFOA 70 ng/L

PFOS 70 ng/L

PFOA + PFOS 70 ng/L

Source: EPA Fact Sheet on PFOA & PFOS Drinking Water Health Advisories, May 2016

PFAA in Local Press

Example of PFOA/PFOS Treatment

Source: City of Oakdale, MNHohenstein, G., “Overview of Remediation Technologies”, Emerging Contaminants Summit, Denver 2016

PFOS better adsorbed than PFOA

System designed for 2,500 gpm

Data is prior to new EPA HA

More frequent change-out will be required.

In Closing

The sky is not falling…

OBG PRESENTS:OBG | THERE’S A WAY

Questions?Thank you!