Produced Water Management:Integrating Recovery, Treatment,

Reuse and DisposalSteve Randtke1, Ted Peltier1, Karen Shafer-Peltier2,

Reza Barati3, Belinda Sturm1, Orion Dollar1,Stan Thompson3, and Abdullah Ibrahim1

1. Department of Civil, Environmental & Architectural Engineering2. Tertiary Oil Recovery Program (TORP)

3. Department of Chemical & Petroleum Engineering

9th Annual KWEA-KsAWWA Joint ConferenceWichita, KansasAugust 29, 2017

What is Produced Water?

• Flowback water– Injected fracturing fluid

returning to the wellhead– Occurs primarily in the

first few weeks • Formation water

– Water from hydrocarbon-bearing formations, or injected for enhanced recovery purposes

– Composition depends on formation chemistry

– Returns throughout production

2

Produced Water Research Program

• NSF-Sponsored Program at KU and West Virginia University

• Goal: Develop management strategies to reduce the impact of oil and gas production on existing water resources and to increase use and reuse of produced water

• Specific Research Objectives1. Treatment of produced water and formation brines to

encourage beneficial use and reuse2. Minimization of freshwater use in oil and gas production3. Assessment of impacts of produced water on aquatic

ecosystems

3

Produced Water Volumes

• Over 20 billion barrels (3.3 billion m3) generated in U.S. in 2012

• KS is 5th largest generator– 1.1 billion barrels (~ 45 billion gallons)

in 2012

• KS volumes stable from 2007-2012– Oil production increased by ~ 20%

• KS wells average ~20 barrels of water per barrel of oil– National average ~ 10 bbl/bbl 0

12345678

Bill

ions

of b

arre

ls

Produced Water Production in Top 5

States, 2012

Data from Veil (2015) and Clark & Veil (2009)

4

Produced Water Volume Compared to Water Use in Kansas in 2012*

In 2012, produced water volume ~2.5% of Kansas water use

Highest water use is for irrigation, primarily from groundwater sources

(*Water use data from KS Dept. of Agriculture and USGS) 1 100 10000

Irrigation

Public Water Supply

Industry

Livestock

Produced Water

Billions of Gallons

5

Oil and Gas Wells in KS (left) and Average Annual Rainfall (below)

•Much of KS has limited water availability

•Produced water reuse could help extend existing resources

6

Produced Water Disposal in Kansas• In Kansas, ~ 2/3 of KS

disposed of by deep-well injection; ~ 1/3 reused by oil & gas producers• Deep-well injection has been

linked to increased seismic activity (induced seismicity)• Area-based restrictions on

deep well injection since 2015• Incentives exist for increased

water reuse and recovery, and for reducing volumes sent to disposal.

Source: Virginia Tech Seismological Observatory

7

8

PRODUCED WATER CHARACTERISTICS

9

Inorganic Constituents

Constituent ( in mg/l)

Barnett (TX) Haynesville (AK, LA, TX)

Marcellus (NY, PA WV)

WesternU. S.

TDS 40,000-185,000 40,000-250,000 45,000-185,000 1,000-400,000

Chloride 25,000-110,000 20,000-150,000 25,000-105,000 ND-250,000

Sodium 10,000-47,000 15,000-55,000 10,000-45,000 ND-150,000

Calcium 2,200-20,000 3,100-34,000 5,000-25,000 ND-74,000

Strontium 350-3,000 100-3,000 500-3,000 ND-6,250

Magnesium 200-3,000 300-5,200 500-3,000 ND

Barium 30-500 100-2,200 50-6,000 ND-850

Iron 22-100 80-350 20-200 ND

Sulfate 15-200 100-400 10-400 ND-15,000

10

Organic Constituents

• Produced Water from Oil Production– Dispersed and dissolved oil– COD up to 1,200 mg/l– Phenolic and aromatic compounds– Polar compounds– Volatile fatty acids

• Produced Water from Gas Production– Can also contain BTEX compounds and other volatiles

11

Examples of Produced Waters Across Kansas

Oakley mg/LTDS 125,000Sodium 45,900Magnesium 512Calcium 1980Strontium 56.0Barium 0.1Chloride 73,900Bicarbonate 133Sulfate 2680

Plainville mg/LTDS 30,600Sodium 11,000Magnesium 46.0Calcium 43.0Strontium 38.0Barium 0.1Chloride 14,000Bicarbonate 4,703Sulfate 696

Vinland mg/LTDS 31,400Sodium 9,030Magnesium 265Calcium 618Strontium 81.3Barium 434Chloride 10,400Bicarbonate 15.5Sulfate bdl

Reno County mg/LTDS 138,000Sodium 39,300Magnesium 2,340Calcium 8,740Strontium 2,220Barium 27.1Chloride 85,000Bicarbonate 55.0Sulfate 43.0

Trego County mg/LTDS 49,100Sodium 33,800Magnesium 2,700Calcium 5,600Strontium naBarium 0Chloride 39,400Bicarbonate 570Sulfate 2,060

•na=not analyzed, bdl=below detection limit

Liberal mg/LTDS 92,700Sodium 29,900Magnesium 1,220Calcium 5,280Strontium 173Barium 0.378Chloride 53,500Bicarbonate 177Sulfate 1,460

Trembley mg/LTDS 128,000Sodium 48,000Magnesium 2,000Calcium 6,900Strontium 2,220Barium bdlChloride naBicarbonate naSulfate 9,000

12

Reuse Barriers: Salinity and Sodicity

• High salinities affect water and nutrient uptake and reduce crop yield.– Non-saline water (TDS < 500 mg/L) safe for all plants– Water with TDS = 500 – 4,000 mg/L may be safe for

more salt-tolerant plants

• Water high in sodium and deficient in other cations, i.e., having a high sodium adsorption ratio (SAR), can cause soils to swell and plug, reducing water infiltration rates.

• Livestock cannot tolerate excessive salt levels.

13

Reuse Barriers: Specific Elements

• Boron – universally safe under 0.5 mg/L, some plants can tolerate up to 15 mg/L – Little information on

current concentrations

• Chloride – universally safe under 70 mg/L, tolerances up to 350 mg/L

Constituent Permanent irrigation MCL (mg/L)

< 20 years irrigation MCL (mg/L)

Aluminum 5 20Arsenic 0.1 2

Beryllium 0.1 0.5Cadmium 0.01 0.05Chromium 0.1 1

Cobalt 0.05 5Copper 0.2 5Fluoride 1 15

Iron 5 20Lithium 2.5 N/A

Manganese 0.2 10Molybdenum 0.01 0.05

Nickel 0.2 2Lead 5 10

Selenium 0.02 0.02Vanadium 0.1 1

Zinc 2 10

•Trace Element Maximum Contaminant Levels assuming good irrigation practices (Lazarova & Bahri, 2004)

14

Reuse Barriers: Additional Concerns

• Radioactivity (e.g., Ra+2)• Scale formation in pipes, treatment systems, wells,

producing formations, storage tanks, membranes, …– Carbonate and sulfate scales, those associated with

Ca+2, Mg+2, and especially Sr+2, Ba+2, and Ra+2

– Iron and manganese oxides– Sulfides

• Corrosivity (CO2, H2S, salinity)• Other constituents (e.g., Ba+2 and Sr+2), esp. those

related to current or future MCLs or water quality standards

15

Two KS Produced Waters Being Studied

All concentrations in mg/l.

Douglas County Reno County

Temperature 18.6 33.8pH 6.6 6.2TDS 31,000 128,000Sodium 9000 48,000Calcium 600 6,900Magnesium 260 2,000Strontium 80 2,400Barium 430 bdlIron 3.1 bdlManganese 0.4 bdlSulfate bdl ~9,000Total C 165 185Organic C 45 15

16

PRODUCED WATER TREATMENT

17

PW Treatment: General Strategy

Initial TSS and oil separation occurs at the well site

Minimal treatment for direct reuse, to prevent scaling or clogging

Salinity reduction required for secondary uses

Removal of particulate matter,oil droplets

TDS reduction/Desalination

Removal of solubleorganics

Removal of NORMs, scale-causing components

PRODUCED WATER

Secondary reuse (‘clean’ water)

Direct industry reuse (reusable water)

18

Treatment to Remove Scale-Forming Cations

• Conventional Treatment Methods– Sodium sulfate addition– Lime and/or sodium carbonate addition (softening)

• Polymer Addition / Polyelectrolyte complex formation– Objective is to form metal-polymer complexes that

can be removed by settling, coagulation and settling, ultrafiltration, centrifugation, or other means

– Polymer recovery/reuse may be necessary to make this economically feasible

• Better if selective for Ba+2, Sr+2, and Ra+2

19

Douglas County: Sulfate Addition

0.00 0.02 0.04 0.06 0.080

25

50

75

100

Am

ount

rem

oved

(per

cent

tota

l)

Na2SO4 added (mmoles)

MgCaSrBa

Douglas County

(Holding time ~ 5 hours to reach maximum removal.)

20

Reno County: Sulfate Addition

0.00 0.02 0.04 0.06 0.080

25

50

75

100A

mou

nt re

mov

ed (p

erce

ent t

otal

)

Na2SO4 added (mmoles)

MgCaSr

Reno County

Minimal Sr+2 removal in absence of Ba+2

21

Douglas County: Carbonate Addition

0.0 0.5 1.0 1.5 2.00

20

40

60

80

100A

mou

nt re

mov

ed (%

tota

l)

0.2M Na2CO3 added to 7 mL brine (mL)

MgCaSrBa

Douglas County

(Adjusted pH to >11 before carbonate addition; removal very rapid)

22

Reno County: Carbonate Addition

0.0 0.5 1.0 1.5 2.00

20

40

60

80

100

Am

ount

rem

oved

(per

cent

tota

l)

0.2M Na2CO3 added to 7 mL brine (mL)

MgCaSr

Reno County

(pH adjusted to >11 before carbonate addition)

23

Polyelectrolytes used as “scale inhibitors”

24

Ba+2 Removal vs Polymer Type/Concentration

0.0 0.5 1.0 1.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

PAA 100kDPAA 250kDPSS 70kDPSS 200kDPSSM(1:1) 20kDPSSM(3:1) 20kDPVS 4-6kDTotal Present

Bariu

m R

emov

ed (µ

mol

es)

Polymer Concentration (percent weight)

25

Sr+2 Removal vs Polymer Type/Concentration

0.0 0.5 1.0 1.5

0.0

0.2

0.4

0.6

0.8

1.0S

tront

ium

Rem

oved

(µm

oles

)

Polymer Concentration (percent weight)

PAA 100kD PAA 250kDPSS 70kD PSS 200kD PSSM(1:1) 20kD PSSM(3:1) 20kDPVS 4-6kD Total Present

26

Best case for Sr+2: Combining pH with UF

2 3 4 5 6 7 8 9 100

10

20

30

40

50

60

70

80

90

100

PSSM(1:1) PSSM(1:1) w/3kD UF PSSM(3:1) PSSM(3:1) w/3kD UF

Stro

ntiu

m (%

rem

oved

)

pH

27

AEROBIC GRANULAR SLUDGE FORMATION IN HYPERSALINE SYNTHETIC PRODUCED WATER

•Inoculated with halophilic

microorganisms (Sporosarcina

halophile)

•Inoculated with a mixed culture

of combined irregular aerobic

granules and flocs

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Aerobic Granule Size & Integrity

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5

Ave

rage

siz

e, m

m

NaCl content, %

Halophile

Mixed

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Halophilic Microorganisms: Image Analysis*

Granule formation Granule maturation Degranulation

NaCl, % 1% 4% 7.5%Avg. Dia., mm 0.24 ± 0.08 1.12 ± 0.18 0.9 ± 0.57

SVI, mL/g 62 ± 27 12 ± 5 22 ± 0.6

VSS/SS 0.76 0.82 0.8

* Ibrahim et al., WEFTEC 2017

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Desalination

• Reverse Osmosis (RO), Multi-stage Flash (MSF) distillation and Multi-Effect Distillation (MED) account for 94% of global desalination capacity

• Energy requirements rise quickly as inlet feeds become more saline

• At TDS 150,000-250,000 mg/L evaporative crystallizers can treat brines with zero-liquid discharge (ZLD) or near-ZLD

Treatment Type

EnergyCost

(kWh/m3)

Treatable TDS Limit (mg/L)

RO 3.5-6.0 ~70,000

MSF 10-28 ~150,000

MED 7-25 ~150,000

Brine Concentrator 18-26 N/A

Brine Crystallizer 52-66 N/A

Brine Concentrator/Crystallizer

70-92 ~250,000

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High Salinity Treatment Options*

Type of Treatment

Pre-Treatments

Treatable TDS Range (mg/L)

% Water Recovery Notes

Evaporative Concentration

De-oiling;antiscalants and

acids if heat transfer fouling

occurs

< 100,000 98

• Very high product water quality;

• Steam produced can be used in Steam-Assisted

Gravity Drainage (SAGD) enhanced oil recovery

methods

CrystallizationSuspended solids

and organic matter removal

No limit (successfullyemployed at

310,000)

0

• Feed brine is completely evaporated

• Potential for commercial recovery of solid salts

• Waste heat from natural gas compressors can drive

separation* RPSEA Project 07122-12, 2009

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Emerging Desalination Methods

• Multiple approaches being developed to reduce energy use and costs, or increase range of treatable waters. – Phase change-based separations (gas hydrate freeze-melting,

supercritical desalination, humidification-dehumidification),– Advanced membrane processes (forward osmosis, membrane

distillation)– Voltage-driven processes (electrodialysis, microbial desalination cells)

• Electrodialysis (ED) and membrane distillation (MD) systems have already been tested on a pilot-scale.

• Freeze-melting and supercritical desalination have the potential to significantly reduce energy requirements.

33

Novel Treatment Technologies (WVU)

• Production of alkaline catholyte in a microbial capacitance deionization cell (MCDC)– Electrochemical production of an alkaline solution,

which is used to precipitate scale-forming cations• Bioelectrochemical Removal of Organics and TDS

Using MCDCs– Using biodegradable organics (in produced water) to

drive biochemical reactions, thereby removing organics while also powering an electrochemical deionization process

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RESERVOIR MANAGEMENT

35

Salinity Exchange for High Salinity Produced Water

High TDS Produced Water

Low Salinity Water FloodingORTreatment and Recovery

“Salinity Exchange”- Dispose High TDS Water- Produce Low TDS Water- Pressure Management

36

Oil-Producing Formations with TDS < 40,000 mg/l

Marked region has production from both ‘high-salinity’ (>100,000 mg/l TDS)and ‘low-salinity’ formations

•Examine chemistry of produced waters and formation materials for exchange suitability

37

Douglas Co. and Reno Co. Mixing Results in PhreeqC

-2.5

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

0 10 20 30 40 50 60

SI p

redi

cted

by

PHRE

EQC

Ratio of Reno County to Douglas County water

Aragonite (CaCO3)

Barite (BaSO4)

Calcite (CaCO3)

Celestite (SrSO4)

Dolomite (CaMg(CO3)2)

38

New & Improved Fracking Fluids

• Energized fluids, including supercritical CO2 foams stabilized with polyelectrolyte complex nanoparticles (PECNPs)– Reduced freshwater use– Better suspension of proppants– Improved oil recovery

• Using Produced Water to Prepare Fracking Fluids– Optimized formulations and salinity levels– Stabilization with PECNPs– Benefits include increased O&G production and

reduced demand on freshwater supplies

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Ongoing and Future Directions

• Kansas Water Office project to demonstrate treatment of high salinity produced water– Treated effluent to flow into a farm pond

• Improved treatment processes– Optimize and improve processes, including those

described above, to enhance performance and reduce cost– Investigate other processes to reduce scale-formation– Investigate processes for boron removal

• Depleted reservoirs to store produced or treated water• Water rights – implications for reuse & recovery• Matching treated-water quality to desired uses• New courses and certificate programs

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Concluding Remarks

• Produced water is a potential water resource for the state of KS• Salinity has the biggest impact on the feasibility of treatment

for reuse.– Treatment costs are much higher above the “RO threshold.”– Pre-treatment will generally be needed to avoid / minimize

membrane fouling.• Removal or control of scale-forming ions is likely to be needed

for some (perhaps many) reuse applications and associated treatment technologies. Depending on water quality:– Sulfate addition can selectively remove Ba+2, but is less

effective for Sr+2 removal; lime/soda softening is expected to be generally effective, but non-selective.

– Removal by polymer addition needs further development.

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Concluding Remarks (Cont’d)

• New or improved treatment technologies are needed to extract freshwater from produced water and to treat produced water for various reuse applications.

• Note that the economics of produced water management differ greatly from those of municipal water management.

• Salinity exchange can help to manage the least treatable waters.– More knowledge is needed about the chemistry of mixing

formation brines.• Oil and gas reservoirs can potentially be managed in a manner

that enhances freshwater production, facilitates various reuse applications, reduces disposal via deep well injection, and supports efforts to control induced seismicity.

42

Acknowledgements

• Produced Water Research GroupKansas University* West Virginia UniversityCollaboratorsEdward PeltierStephen RandtkeKaren PeltierReza BaratiBelinda SturmJyun-Syung Tsau

StaffRay Carter Jr.Mark Ballard

Post-Doctoral ResearchersMing Chen, Karla Leslie,Masoumeh Veisi, Sheng-Xue Xie

CollaboratorsPaul ZiemkiewiczLian-Shin LinJoseph DonovanHarry FinkleaJ. Todd PettyShawn Grushecky

StaffJennifer Hause

Post-Doctoral ResearchersEric Merriam

*All contributed to the work described herein.

43

Acknowledgements (Cont’d)

• Research Partners & Collaborators– Kansas Water Office– Kansas Geological Survey– Kansas Biological Survey

• Graduate & Undergraduate Student Researchers– Eric Albertson* Andrew Hummel Negar Nazari– Rudhra Anandan Abdullah Ibrahim* Marshall Rutter– Orion Dollar* Francis Kinney* Stan Thompson*– Hooman Hosseini Colton Kenner* Jennifer Warren

*Contributors to this presentation; all other have contributed to the work described herein and/or are contributing to on-going work.

44

Acknowledgements (Cont’d)

• Special thanks to those doing the dirty work

45

Acknowledgements (Cont’d)

• Funding Sources– National Science Foundation, EPSCoR Research

Infrastructure Improvement Program: Track-2, Focused EPSCoR Collaboration Award(OIA-1632892)

– KU Strategic Initiative Grant– Tertiary Oil Recovery Program – KU Dept. of Civil, Environmental & Architectural Engrg.– Others in progress …

46