sustainable removal of poly- and perfluorinated alkyl ......2016/11/09 · presentation outline 1....

© Amec Foster Wheeler 2016.

Sustainable Removal of Poly- and Perfluorinated Alkyl Substances (PFAS) from Groundwater Using Synthetic Media

Nathan Hagelin, Amec Foster Wheeler; Steve Woodard, ECT

Presentation Outline

1. The team: Amec Foster Wheeler and ECT

2. PFAS sources, regulations and treatment challenge

3. An effective PFAS treatment technology: Synthetic Ion Exchange

Media

1. Bench testing results

2. Pilot testing results

3. Full-scale design

4. Ongoing Research

2

Sources of PFAS include firefighting

foam, TeflonTM, ScotchgardTM, Gore-

Tex®, etc.

USEPA has issued a combined

drinking water Health Advisory Level

(HA) for:

Perfluorooctane sulfonate

(PFOS) = 70 ppt

Perfluorooctanoic acid

(PFOA) = 70 ppt

The carbon-fluorine bond is one of

the strongest in nature

Granular activated carbon (GAC) is

accepted technology, but has

limitations

.3

PFAS Sources, Regulation and Treatment Challenges

Challenge: Remediation –State of the Practice

Contaminants of Emerging Concern – few proven

technologies

Recalcitrant compounds – tough bonds to break

Lack of enforceable standards – wait and see approach

Emergency response mode – must use proven technology

to address completed exposure pathways

Most sites have not progressed beyond SI/RI

Few opportunities to date for field-scale trails – coming

soon

Proven technologies have limitations and are expensive

© Amec Foster Wheeler 2016.4

An Urgent Opportunity for Technology

Widespread groundwater contamination emerging nationwide at

military installations, airports, refineries and industrialized communities

Widespread use of AFFF resulting in persistent groundwater plumes

Emergency response at municipal and private drinking water supplies

Fisheries shut down at some sites

Widespread and troubling media coverage

Proven technologies (primarily GAC) have shortcomings

Innovation needed

.5

Bench Test Methodologyand Results

Isotherm Testing

Column Testing

Regeneration

Synthetic Media surfaces as potential solution

Synthetic media (resins)

removes various contaminants

from liquids, vapor or

atmospheric streams

Isotherm testing to identify

potentially effective media

Potential for indefinite reuse via

regeneration

7

Media Selection

Ion Exchange

Polymeric

Carbonaceous

Isotherm Results

.8

Bench Test PFAS Influent Concentrations

PFAS Compound Average Influent Concentration (µg/L)

PFOA 0.291

PFOS 3.33

Other PFAS 3.11

Total PFAS 6.73

9 .

10

Bench Test Setup

Add a coloured

transparent

segment and

caption if

required.

.

Control

Resin A

Resin B

Resin C

Feed

pump

Ground

-water

drum

Isotherm testing

narrowed down the

field to 3 top performing

synthetic media (ion-

exchange resins).

Column tests evaluated

the ability of the resins

to remove PFCs from

the groundwater.

11

Adsorption and Regeneration of Leading Resins from Column Testing

-

50,000

100,000

150,000

200,000

250,000

300,000

350,000

400,000

450,000

PF

AS

Mass (

ng

)

Resin A Resin B Resin C

PFAS MassDelivered

PFAS MassRemoved

PFAS MassRecovered

Adsorption of PFCs to resin

below detection limits

No breakthrough observed

>99% regeneration of

media with solvent/brine

solution

Success of bench test led

to a pilot test for evaluation

at the Site

12

Final Outcome of Bench Test

Add a coloured

transparent

segment and

caption if

required.

Sorbix A3F

A strong base anion exchange resin

Pilot Test Setup and Methodology

Influent Characterization

Process Design

Results

Site 8 Layout

14

Pilot Test PFAS Influent Concentrations

PFAS Compound Average Influent Concentration (µg/L)

PFOA 11.5

PFOS 27.4

Other PFAS 55.6

Total PFAS 94.5

15

• Concentrations approximately 15 times higher than bench test


Pilot Test Process Flow Diagram


Pilot Test General Arrangement

Process

pumps

Cartridge filters

for solids removal

GAC (front)

and resin

(rear) vessels


Ion Exchange Vessels


PFOA Breakthrough Results

0.001

0.01

0.1

1

10

100

0 10,000 20,000 30,000 40,000 50,000

PFO

A (

ug

/L)

Bed Volumes

Influent

Lead GAC

Lead Resin

Lag GAC

Lag Resin

EPA PFOA+PFOSHA

PFOA breakthrough at 5-min EBCT


PFOS Breakthrough Results

0.001

0.01

0.1

1

10

100

0 10,000 20,000 30,000 40,000 50,000

PFO

S (u

g/L

)

Bed Volumes

Influent

Lead GAC

Lead Resin

Lag GAC

Lag Resin

EPA PFOA+PFOSHA

PFOS breakthrough at 5-min EBCT


Precursor


3 Carbons


4 Carbons


6 Carbons


7 Carbons


9 Carbons


Volume Treated Before Breakthrough:All Observed PFAS


Successful Regen at Pilot Scale

0.0

1.0

2.0

3.0

4.0

5.0

6.0

- 1,000 2,000 3,000 4,000 5,000 6,000 7,000 8,000

Tota

l PFA

S C

on

cen

trat

ion

(p

pb

)

Volume Treated (Bed Volumes)

Total PFAS Concentration from Lead IX Media Bed

Virgin Media

Post Regen

Why is Ion Exchange so effective?

34

Regeneration tells the story – ion exchange and adsorption combined

• Ion exchange resin is a strong adsorbent with ion exchange functionality

• The resin has high affinity for PFOA (carboxylate head) and PFOS (sulfonate head). Over time, PFOA and PFOS replace other anions on the resin

• Regeneration with solvent-brine solution

o High concentration salt dislodges the anionic heads of PFAS molecules from the resin

o High concentration solvent desorbs the PFAS molecules from the resin

IX Resin takes advantage of the unique properties of PFAS to both exchange ions and adsorb

Path Forward - 2 full-scale designs

Aims

600

gpm

Path Forward - 2 full-scale designs

Site 8

200

gpm

Full Scale Application

37

Lifecycle cost evaluation performed for full-scale 200 gpm system at Pease

AFB (Site 8)

Capital cost for Resin system is +/- 15% higher than GAC Media cost

Regeneration system

O&M cost is +/- 50% lower than GAC Resin has higher capacity

No media replacement

Even without regeneration (resin exchange program), lifecycle cost of resin

system is lower, depending upon PFAS mix

Two full-scale systems in detailed design Site 8: 200 gpm; AFFF source area

AIMS Site: 600 gpm; up-gradient of Haven drinking water well

Both systems scheduled to start up next Fall

Ongoing R&D


►Iron sequestration at Pease using pilot scale vessels

►Multiple regenerations for resin longevity testing

►Distillation optimization for spent regenerant solution

► Reduce in solvent use

► Reduce distillation time

►Alternative regeneration solutions

► Ammonium chloride

► Ammonium hydroxide

► Ethanol

► Various salt combination

►Alternative media testing – Sorbix A3F compared to

► Other commercial IX media

► Carbonaceous GAC

► Coconut GAC

Market Opportunities for IX


►Drinking water applications – UCMR3 data

► Municipal supply

► Point of use

►Pre-treatment or polish on GAC systems, and vice versa

►Single use / exchange or regeneration systems

►On-site regeneration

►Centralized regeneration

►Concentrated brine

disposal

►In-Situ Applications

Nathan HagelinAmec Foster [email protected](207) 232-6968

Steve [email protected](207) 210-1551

Thank you to our co-authors:Brandon Newman, Amec Foster WheelerMike Nickelsen, ECT2

Questions?

sustainable removal of poly- and perfluorinated alkyl ......2016/11/09 · presentation outline 1....

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