Remediation of CCl4

DNAPL at Spanish Site

Ian Ross Ph.D.,

FMC Environmental Solutions

Health and Safety

• Project Team wearing FMC baseball cap

• Logistics –flight times / taxi’s

• Hotel –exits, facilities, tapas, drinks

• Bus –entry exit / traffic

• On site –No entry into remediation area –remain at boundary

–Trip Hazards –uneven ground

Air Pollution Control

FMC offers SOx and NOx abatement product technologies for coal-fired plants.

Natronx, LLC, EnProveTM sodium sorbents are engineered to remove SO2, SO3, HCl and HF

from stack gases.

FMC’s patented PerNOxide™ technology, licensed from NASA, uses H2O2 to oxidize nitrogen

oxide (NO) and elemental mercury (Hg˚) in flue gas into forms that can be captured by flue-

gas scrubbing devices.

Soil and Groundwater Remediation

FMC’s Klozur® persulfate, Daramend® bioremediation technology, and the EHC® family

of integrated carbon & ZVI technologies, are available globally to provide cost effective

solutions for the remediation of contaminated soil, groundwater, and sediments.

Water Treatment

FMC VigorOx® peracetic acid is a safe and environmentally-benign biocide. FMC can work

directly with customers to understand their unique challenges and develop turnkey solutions

tailored to meet their specific treatment needs while ensuring compliance with individual

state regulations. Our proven water treatment applications include the wastewater and the

oil services industries.

59-01-EIT-DL

Presentation Outline

• FMC Environmental Solutions

• In Situ Chemical Oxidation and Surfactants

• Site History

• Project Overview

• Site Investigation

• Remediation Implementation • Results

What is In Situ Chemical Oxidation?

ISCO Basics

• Addition of Oxidants into the subsurface to facilitate the conversion of recalcitrant and toxic compounds to CO2 and H2O or less toxic / more biodegradable intermediates

• ISCO reduces contaminant mass through the oxidation process

• Suitable for saturated and/or vadose zone source and plume treatment

• Application generally via

– injection to aquifers

– soil mixing to more cohesive lithologies

• ISCO maybe combined with other techniques (e.g. enhanced or monitored natural attenuation)

Persulfate

Advantages

• Oxidation mechanisms via direct oxidation (relatively strong) and production of radicals (sulphate SO4˙ and hydroxyl OH˙)

• Thermodynamically very strong –can oxidise multiple organic compounds

• Does not produce gaseous breakdown products or significant heat

• Persist in the aquifer for multiple months

• Reaction rate and thus persistence can be controlled by activation method

• High aqueous solubility (>40%) for diffusion and advection –large ROI

• Can be activated over a wide range of geochemical conditions

• Can be mixed into unsaturated soils to destroy a wide range of target organics

• Ease of handling as oxidant is supplied as a granular solid

• Leaves residual sulfate in formation to stimulation biodegradation

Disadvantages

• Persulfate without activation is kinetically slow to react

• Corrosive / material compatibility

• Have to add an activator

Granular Persulfate

Chemistry and Stoichiometry

S2O8-2 + 2H+ + 2e- 2HSO4

-1

1. Direct Oxidation:

2 S2O8-2 + C2Cl4 + 4 H2O 2 CO2 + 4 Cl- + 4 H+ + 4 HSO4

-1

3 kg / kg

persulfate anion

PCE

2. Radical Formation:

However, persulfate anion kinetics are generally too slow for most contaminants. As a result, you

must activate persulfate to form the sulfate radical.

S2O8-2 + activator SO4•- + (SO4•- or SO4

-2)

• Activation produces a radical which is more powerful and kinetically fast

• Radicals propagate and stoichiometry is not possible.

• FMC always recommends using an activator

A stoichiometric equation can be derived e.g. for PCE

Klozur® Activated Persulfate

produces a radical which is more powerful and kinetically fast

FMC always recommends using an activator

proper activation method is based on contaminant, site lithology, and hydrogeology

Klozur® Persulfate Chemistry

S2O8-2 + activator SO4•- + (SO4•- or SO4

-2)

Heat Iron H2O2 High pH

Purchase of FMC’s Klozur® Persulfate includes rights to practice

the inventions covered by the patents in the purchase price of the product.

Sustainable Solution: Utilizes Hydroelectric Power

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Competitive Scope

volts

F2 3.0

OH• 2.7

SO4• 2.6

O3 2.4

S2O8-2 2.1

H2O2 1.8

MnO4- 1.7

HClO 1.6

Cl2 1.4

ClO2 1.3

ClO4- 1.4

stro

ng

er o

xid

ize

r

Fenton’s

•Treats wide range of contaminants

•Short subsurface lifetime

•Difficult to apply in reactive soils

Ozone

•Treats wide range of contaminants

•Short subsurface lifetime

•Limited use in saturated zone

Permanganate

•Treats limited range of contaminants

•Long subsurface lifetime

•Potential effects on hydrogeology

Klozur® Activated Persulfate

•Treats wide range of contaminants

•Sulfate radical forms slower than

the hydroxyl radical, allowing a larger

radius of influence

Higher the oxidation potential the stronger the oxidizer

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Klozur® Persulfate Activation Chemistry

Primary Methods to Activate Klozur® Persulfate

1. Heat

• Kinetically Fast (Reaction Kinetics with Contaminant)

• Capable of Destroying Wide Range of Contaminants

• Temperature Range: 35 – 45º C

[FeEDTA]

2. Metal Chelates

• Slower Reaction Kinetics (Extends Persulfate Lifetime in Subsurface)

• Capable of Destroying: Chlorinated Ethenes, BTEX, PAHs, MTBE

• Target in Groundwater: 150 - 500ppm soluble Fe

M+2

Chelant

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Klozur® Persulfate Activation Chemistry

3. Hydrogen Peroxide

• Kinetically Fast (Reaction Kinetics with Contaminant)

• Capable of Destroying Wide Range of Organics

• Benefit of two powerful radical species.

• Typical Concentration Ratio: 5:1, moles peroxide : mole persulfate

4. High pH / Alkaline Activation

• Kinetically Fast (Reaction Kinetics with Contaminant)

• Capable of Destroying Wide Range of Organics

• pH between 10.5 – 12 (maintained while the Klozur is present)

• Pre-treatment titration is needed to determine the soil’s natural pH

resistance

S2O8-2 + H2O2 → 2SO4• + 2OH•

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Klozur® Activated Persulfate

Chlorinated Solvents

PCE, TCE, DCE

TCA, DCA

Vinyl chloride

Carbon tetrachloride

Chloroform

Chloroethane

Chloromethane

Dichloropropane

Trichloropropane

Methylene chloride

TPH

BTEX

GRO

DRO

ORO

creosote

Oxygenates

MTBE

TBA

Chlorobenzenes

Chlorobenzene

Dichlorobenzene

trichlorobenzene

Phenols

phenol

Pentachlorophenol

nitrophenol

Freons

Pesticides

DDT

Chlordane

Heptachlor

Lindane

Toxaphene

MCPA

Bromoxynil

PAHs

Anthracene

Benzopyrene

Styrene

Naphthalene

Pyrene

Chrysene

trimethylbenzene

Others

Carbon disulfide

PFOS / PFOA

Aniline

PVA

TNT / DNT

1,4 Dioxane

Examples of Contaminants Destroyed by Klozur Persulfate

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Oxidation State Examples

C C

Cl H

Cl Cl

PCE = +2

C C

Cl Cl

Cl Cl

C C

Cl Cl

Cl Cl

+

+ +

+

-

- -

-

C C

Cl H

Cl Cl

+

+ +

-

- -

+

-

Cl

C

Cl

Cl Cl

+

-

+ +

+

Cl

C

Cl

Cl Cl

-

- -

TCE = +1 / +2 CCl4 = +4

H

C

H

H H

H

C

H

H H

CH4 = -4

- -

-

-

+ +

+ +

Klozur® Activated Persulfate Application Methods

Direct push

Fixed well

In situ soil mixing

Ex situ soil mixing

Forming a persulfate solution

Fixed wells

Direct push rig In situ mixing 59-01-EIT-DL

Technology Background: S-ISCO®

Surfactant-enhanced In Situ Chemical Oxidation

www.verutek.com

• VeruSOL desorbs & emulsifies NAPL/sorbed

contaminants o Brings into aqueous phase

• Activators generate free-radicals o Sulfate radicals (SO4•

- or SO4-2)

o Hydroxyl radicals (OH∙)

• Free radicals oxidize aqueous-phase contaminants

• Primawave Pressure-Pulsing Injection Enhancement • Wavefront Technology Solutions US Inc

VeruSOL®

Biodegradable,

Plant-based Surfactant

&

Co-solvent Mixtures

Free Radical

Oxidant Systems

Safe, Permanent

Source

Destruction

Remedial Technologies for In Situ Treatment

Less Hydrophobic

• Ethanol

• Acetone

• MTBE

• Methylene chloride

• Vinyl chloride

• Ketones

• 1,2 DCA

• Chloroform

Hydrophobic

• Diesel & gasoline

• BTEX; benzene, xylene, toluene, ethyl benzene

• Naphthalene

• Chlorinated solvents; PCE, TCE

• Heating oil

• Nitrophenol

• Often found at fueling/petro stations, manufacturing sites

Very Hydrophobic

• PAHs; acenapthene, anthracene, benzo(a) pyrene, benzo (b) flouranthene

• Heavy fuel; # 6 oil

• Often found at creosote, gas works or MGP sites

When to Use Surfactant

• S-ISCO with VeruSOL & alkaline-

activated persulfate destroyed 96%

SVOCs and 99% PAHs in 28 days

• VeruSOL-3 increased solubility up to 29x

0

100

200

300

400

500

600

700

800

0 2 5 10 25

Co

nce

ntr

atio

n (m

g/L

)

VeruSOL-3 Concentration (g/L)

Solubility Enhancement with VeruSOL-3: VOC & SVOC Concentration vs Surfactant Concentration

SVOCs

VOCs

0

50

100

150

200

250

300

350

400

NONE Alkaline Activated Persulfate (100 g/L, pH>12)

Conc

entr

atio

n (m

g/kg

)

Column Condition

Day 28: Concentrations of Total SVOCs & PAHs

SVOCs (mg/kg)

PAHs (mg/kg)

www.verutek.com

Remedial Design: Typical Treatability Study

S-ISCO incorporates VeruSOL– plant-based & biodegradable surfactant/co-solvent mixtures into oxidation systems to address bound & NAPL contamination (Figure A).

• VeruSOL increases the solubility of contaminants that have normally low solubility (e.g

NAPLs), making them available for oxidative destruction.

Volume: 1.4 m3 Surface area: 20 m2 Volume: 1.4 m3 Emulsion Diameter: 1 millimeter Surface area: 8,495 m2 Approximately 2.5 orders of magnitude higher

Volume: 1.4 m3 Emulsion Diameter: 1 micrometer Surface area: 8,499,978 m2

Approximately 5 orders of magnitude higher

Emulsification and Surface Area

10’

0.5’

10’

Emulsions increase interface area between oxidant and contaminant by several orders of magnitude

Groundwater

NAPL

Products Made at the Site

May 8, 2013

May 8, 2013

• Facility closed • Land held on Leasehold basis –handback in progress • Remediation required as part of process to return land • Elevated concentrations of CCl4 (>540 mg/L) and DNAPL droplets observed plus other chlorinated VOC’s • Geology comprises fine sands to approx. 45m where clay layer exists • Groundwater shallow (3 m bgl), saline water (intrusion at 30m bgl) • Negligible hydraulic gradient • VOC’s at elevated concentrations at depth (40-45m) • Investigations indicate point source • Remediation focussed on mass removal (DNAPL) • After thorough technical review of all available remedial techniques surfactant enhanced in situ chemical oxidation was chosen • Klozur® persulfate with NaOH activation and Verusol were both injected to the DNAPL source zone • Concentrations of cVOC’s were depleted by >98% in the main DNAPL zone within 3 months • Negligible increases in cVOC’s were observed in surrounding monitoring wells • Further groundwater monitoring is ongoing

Project Outline

Site Investigation

May 8, 2013

• Site Investigations to depth performed using differing drilling techniques:

• Water flush • Air flush • Core recovery

• Source Area Defined • Limited spatial area, • Defined deep source

• High natural organic matter (high Foc) • Black anaerobic water • Chloride from saline intrusion • DNAPL at depth-comprised >90% of contaminant mass

Geology

May 8, 2013

Unit A. Concrete Slab

Unit B. Clayey Made ground

Unit C. Brown sand with silt

Unit D. Black Siliceas Sands

Unit E. Sands interbedded with organic silts

Unit F. Black organic silts

Legend

Cross Section

May 8, 2013

Unit A. Concrete Slab

Unit B. Clayey Made ground

Unit C. Brown sand with silt

Unit D. Black Siliceas Sands

Unit E. Sands interbedded with organic silts

Unit F. Black organic silts

May 8, 2013

Laboratory Work

May 8, 2013

• Laboratory Tests performed using site soil and groundwater • Soil Oxidant Demand determined • Treatment efficacy confirmed

• Persulfate activation methods tested • Kinetics of oxidation with increasing oxidant concentrations

• Aquifer pH buffering capacity evaluated

Lab Results

May 8, 2013

Site Work

May 8, 2013

Infrastructure

May 8, 2013

Well cleaning

Liquid Silicates from

manufacturing plant

May 8, 2013

Persulfate distribution

May 8, 2013

Results

May 8, 2013

• Injection of alkaline activated Klozur persulfate (65 tons) and Verusol to wells Fac2 and Cas6c • cVOC concentration decreases observed in all wells screened across deeper area • Electrical conductivity increases observed as a result of oxidant • cVOC’s in groundwater from Fac2 decreased by 98% in 3 months • cVOC’s in groundwater from remaining deep wells decreased by 87% in 3 months • Further groundwater monitoring ongoing

May 8, 2013

Results

May 8, 2013

Results

May 8, 2013

Summary

• Remediation required as part of process to return land • Elevated concentrations of CCl4 (>540 mg/L) and DNAPL droplets observed plus other chlorinated VOC’s •VOC’s at elevated concentrations at depth (40-45m) • Investigations indicate point source • Remediation focussed on mass removal (DNAPL) • Klozur® persulfate with NaOH activation and Verusol were both injected to the DNAPL source zone • Concentrations of cVOC’s were depleted by >98% in the main DNAPL zone within 3 months • Further groundwater monitoring is ongoing

Questions?

Our remediation chemistries have had a positive impact in the communities in which we live and do business. We believe sustainability demands the use of the right chemistry - building on sustainable innovation, operations, and business practices - as we seek to grow and improve the quality of people’s lives everywhere. The use of hydropower in our manufacturing process contributes significantly to our sustainability initiative; having one of the lowest carbon footprints in the environmental market for chemical remediation technologies.

Ian Ross Ph.D.

Technical / Business Manager EMEA

FMC Environmental Solutions

Phone: +44 (0)7855745531

ian.ross@fmc.com

www.environmental.fmc.com