By Ron Sc

Lynn HLarry M

An Innovative Approach to Managing P

Water and Frac Flowback in the Marcel
Somerset Regional Water Resource

• Buildin

g several commercial frac flowback

and produced water management facilities

• First is in Somerset Count

y, P

A

• MWH was retained for permitting, 

engineering, and construction services

• Awaiting construction permit•

U que app oac o a e a age e nique app

roach t

o w

a

t

er m

a

nage

m

ent 
Lack of Sufficient Water Supply is 

Limitin

g O&G Production

• Need 1 to 8 Millions 

g p allons of water 

per we

for hydrofracturing

• Surface Water Withdrawals 

– Concerns about depletion of water resources, 

especially in drought years

– Impacts to aquatic life– Negative publicity– Ability to get withdrawals approved Ability to get withdrawals approved– Cost can be significant ($0.1/bbl to $2/bbl

)

– Don t’ really need high quality water, but really need high quality water, but

consistent quality is important
Required Water Quality for Fracing

• Largest water use for production

• Desired water quality varies• General guidelines

Frac Water Quality Requiremen

Chlorides <30,000 typical but up to 9

Hardness <2 500 mg/L <2,500 mg/LCalcium <350 mg/LTSS <50 mg/L

TDS <50,000 mg/L typicalIron <20 mg/LBacteria <100 cells/100mLOil <25 mg/L
Acid Mine Drainage

An Alternative Water Source

• Pennsylvania Pennsylvania s’ single greatest source single greatest source

of water pollution

– Contaminated 3,000 miles of streams

• Often has low pH (<5) and elevated 

levels of iron and sulfate

• Can have elevated hardness• TDS typ y , g icall

y around 1,000 m

g/L

• Treatment is required prior to surface discha• But suitable as suitable as frac water with little or no trea

with little or no trea
Wastewater Management is also a 

Limitin

g Factor in O&G Production

• Frac Flowback

– Hi h fl f h t d ti Hi

g

h flows 

for s

hor

t

duration

– 10 to 40% of frac fluid recovered– Most recovered in first 1 to 2 weeks Most recovered in first

1 to

2 weeks

– TDS quickly climbs to 30,000 mg/L up to 200,0– Contains numerous chemical additives and na

Contains numerous chemical additives and na

occurring constituents

• Produced Water

– Lower flows (2 to 30 bpd per well)– Potentially very high TDS (100,000 to 300,000 – Continues to flow for the life of the well
Frac Flowback & Produced Water 

Mana

g g ement Strate

gies

• Evaporation in pits/ponds w/enhancements Evaporation in pits/ponds w/enhancements• Injection/disposal wells• Discharge to POTW Discharge to POTW• Direct reuse for drilling and fracing• Treatment for reuse or surface discharge Treatment for reuse or surface discharge• Thermal/mechanical evaporation• E ti /di till ti f f 

Evaporation/di

still

ation 

for reuse or surface 
Evaporation (from ponds)

• Natural pond evaporation not practical

–

>40 i / n

/yr precip & 30 i / & < 30 in

/yr evap

– Poor evaporation at high salinity

– Crusting over Crusting over
Evaporation (from ponds)

• Use of sprayers can enhance evaporation • Potential Issues

– Regulatory hurdles– S lt d iti i t l i t S

alt

deposition environmen

t

al impac

t

s

– Odors and VOC emissions

• Ponds may still be part of management str

Ponds may still be part of management str
Injection or Disposal Wells

• Significant regulatory hurdles Significant regulatory hurdles

– Impacts to water supply aquifers– Potential for injected water to migrate to stream

Potential for injected water to migrate to stream

• Limited capacities (1200 to 3000 bpd)• Substantial capital investment with uncerta

Substantial capital investment with uncerta

span ($1M to $2M)

• Probably will only play a limited role Probably will only play

a limited role

• No new injection wells have been permitte
Discharge to POTW

• POTWs are biolo

g p ical 

processes such as 

lagoons, trickling filters, or activated sludge 

• Biolo

gy g 

ical s

ystems cannot handle hi

gh salin

-few case studies above 35,000 mg/l

• Need to understand POTW dischar

ge limits 

the treatment processes used, flow variabilit

• Potential for VOC emissions issues at POTW

• If high TDS + flow is significant portion of PO

influent, this is not an option

• Regulatory limitations on acceptance
Direct Reuse for Drilling and Fracing

• Not a viable option for Marcellus• TDS is too high• Chlorides, in particular

– Corrosion concerns– Impacts on fracing

• Solids,hardness, and bacteria removal

– Chemical conditioning, separation, filtration

• Sulfides control

– Safety, corrosion, SRB downhole concerns

• R li f h i l dditi Recycling o

f c

hemical additives
Typical Water Quality

Samples of Frac Flowback and Produced Water Quali

(All in mg/L) FFB Grab FFB Pit Produced Water SRWTDS 64,800 44,627 222,000 38,0Chloride 35 900 , 27 096 , 145 000 145,000 31 0

,

TSS 1,910 765 398Hardness 11,800 9,197 67,300 3,70Calcium 4,130 3,236 23,200 770Iron 40 12 99 80B i ar um 802 1 450 , 15 700 , 1 03

,

*Includes some pit waters and drilling mud waste
Treatment & Evaporation are the On

Viable Mana

g g ement Strate

gies

• Evaporation in pits/ponds w/enhancements Evaporation in pits/ponds w/enhancements• Injection/disposal wells• Discharge to POTW Discharge to POTW• Direct reuse for drilling and fracing• Treatment for reuse or surface discharge Treatment for reuse or surface discharge• Thermal/mechanical evaporation• E ti /di till ti f f 

Evaporation/di

still

ation 

for reuse or surface 
Treatment and Evaporation Technol

Salinity Reduction Salinity Reduction Maximum Feed TDS Energy

Technologies

Maximum Feed TDSmg/l

Energy

kWh/100 b

Capacitive Deionization 5,000 20

Electrodialysis Reversal (EDR) 7,000 60Electrodialysis (ED) 42,000 -Reverse Reverse Osmosis Osmosis 50 000 , 15

-30

VSEP 35,000 15-30Dewvaporation 100,000 to 150,000 150-400Membrane Distillation 250,000 600-700Evaporator/Concentrator 100,000 400C t lli Crys

t

allize

r 250 000 t 350 000 250,000

to 350,000 1000

-1300
Treatment versus Evaporation/Disti

• Membranes are generally less expensive 

than e aporators e en tho gh significant than

e

vaporators, 

e

ven tho

ugh significant

pretreatment is required

• Therefore Salinity ( Therefore, Salinity

(NaCl) level controls ) level controls

decision

• TDS > 50 000 mg/l is not practical to TDS

> 50,000 mg/l is not practical to

treat with membranes (prefer 35,000 mg/l )
Crystallize

100

ry (%)

Evaporation

er Recove 75Wat Limited Recovery at 

Higher TDS 50

Total Dissolved Solids (mg/l)

25,000 50,000 100,000 30
Treatment versus Evaporation/Disti

• High TDS High TDS (>35 000 mg/L) (>35,000 mg/L) water needs to be water needs to be

blended if membranes are to be used

• Could capture first few days of Could capture first few days of flowback flowback for

treatment, but this creates logistical issues

• Membranes 

g j enerate a reject stream to 

manage and will need an evaporator and crystallizer anyway
SRWR Approach

• Segregate trucks based on conductivity• Storage in separate ponds• Purchased property with AMD as low TDS 

water source

• Blend as needed to provide:

– High chloride frac water(15,000 to 30,000 mg/L)– Low chloride frac water (<2,000 mg/L) – Surface discharge quality water
Conceptual Process Flow Diagram

TDS <2,000 mg/L

High Chlori

1 AMD

Frac Wate

EAR

LY

Chem

PPT/

Filt.

RO

OWS

2

EAR

LY

STAGE

FFB

Low Chlori

Frac Wate

Reject

TDS <30,000 mg/L

OWS

TDS >30,000 mg/L

3

LATE

STAGE

FFB & PW

Chem

PPT/

Filt.

Evap

&

Distill.

Fresh Wate

Slurry

Cr

ystallizer

Salt
SRWR Approach (cont’d)

• Focus on consistent water quality• Require operators to take water back• Minimize surface discharge 

– Wasting a resource – Very stringent discharge limits
SRWR Discharge Limits

Parameter Effluent Limit Detection

Limit

U

TDS 500 mChloride 250 mTSS ND 4 mBOD (methanol concern) 8.35 m

O&G ND 1.4 m

Phenols ND 0 002 . mNaphthalene 0.053 mAluminum ND 0 003 . mStrontium ND 0.0003 mBoron 1.99 mBenzene 0.001 mIron ND 0.001 m
Does Blending Make $ense?

• Is it less expensive to treat AMD separatel

Is it less expensive to treat AMD separatel

from FFB and PW?

OR
$80.0

$60.0

$70.0

$50.0

llions nd O&M

$40.0

Cost in $Mi

ed Capital an

$20.0$30.0

Annual 

Amortiz

e

$10.0

$0.0

123

Basis of $5/bbl for evap
$90.0

$100.0

$70 0$80.0$60.0$70.0

 O&M

$40.0$50.0

in $Millions

Capital and 

$20.0$30.0

Cost 

Amortized 

$0 0

$10.0

$0.0

$1.50/bbl $2.50/bbl $5.00/bbl $7.0

Evaporation Unit Cost
FFB and PW Have High Fouling Pote

• Reversible fouling

– Particulate, scale, or slime

Temperature pH adjustment

• Biofouling

– Slime

– Temperature, pH adjustment, 

surfactants

• Inorganic

C l i b i i ili

– Biocide/high pH, tem

• Irreversible fouling

– Cleaning study

–

C

alcium, 

barium, iron, silica, 

strontium

– Low pH, temperature 

O i

– Cleaning study

• Temperature drop in 

– Reduces solubility

•

Organic

– Dissolved organic carbon– High pH, temperature

– Solidification of para– Particulate and para
Operational Operational Parameters and Conditio

Parameters and Conditio

Desalination Membranes Desalination Membranes

Parameter Nanofiltration Reverse OsmoMax. Feed Pressure 600 psi 1,500 psiMax. TDS - 50,000 mg/lWater Recovery Water Recovery 75-90% 40-80%Solid Phase Mitigation Strategy and Operatin

Limitations

Cli C b t Calcium Carbonate D H LSI Depress pH, LSI <2 5. - 3 2.Calcium Sulfate Antiscalant, Ω < 2-400Strontium Sulfate Antiscalant, Ω < 43-50Barium Sulfate Antiscalant, Ω < 50Calcium Fluoride Antiscalant, Ω < 16,000Iron Antiscalant, Antiscalant, <8 ppm FeSilica: Reactive Nonreactive Antiscalant, < 120 ppm
Multi-Stage Pretreatment Required

• Gross oil and solids removal• Softening• Particulate removal

– Coagulation, sedimentation, media filters, MF/U

• Ion exchan

g

e

• Organics reduction vs control of fouling• De

gasification for CO

2 reduction

• Acid addition• Antiscalants
Ongoing Issues

• Pretreatment to control fouling/scaling Pretreatment to control fouling/scaling• Radionuclides• VOCs• Residuals management• E i ti i fl t b 

Economics over time as influent becomes 

produced water
Somerset in Summary

• Filling a need for centralized water manage

facilities for O&G industry

• T i f ll i Treating two sources o

f pollution

• Reduce overall treatment costs by blending

• Generating an alternative fresh water sourc• Reduce O&G industry’s need to use surfac• Can recover some minerals• Minimize amount of wastes for disposal
Thank You! Thank You!