By Ron Schlicher/MWHLynn Haas/MWHLarry Mostoller/SRWRAn Innovative Approach to Managing ProducedWater and Frac Flowback in the Marcellus ShaleSomerset Regional Water Resources• Buildingseveral commercial frac flowbackand produced water management facilities• First is in Somerset County, PA• MWH was retained for permitting,engineering, and construction services• Awaiting construction permit•Uniqueapproach towater managementque app oac o a e a age eLack of Sufficient Water Supply isLimitingO&G Production• Need 1 to 8 Millionsgallons of waterper wellpfor hydrofracturing• Surface Water Withdrawals– Concerns about depletion of water resources,especially in drought years–Impacts to aquatic life– Negative publicityAbility to get withdrawals approved–Abilitytogetwithdrawalsapproved– Cost can be significant($0.1/bbl to $2/bbl)–Don’really need high quality water, buttreallyneedhighqualitywater,butconsistent quality is importantRequired Water Quality for Fracing• Largest water use for production• Desired water quality varies• General guidelinesFrac Water Quality RequirementsChlorides <30,000 typical but up to 90,000 mg/LHardness<2 500 mg/L<2,500mg/LCalcium <350 mg/LTSS <50 mg/LTDS <50,000 mg/L typicalIron <20 mg/LBacteria <100 cells/100mLOil <25 mg/LAcid Mine DrainageAn Alternative Water Source•Pennsylvania’single greatest sourcePennsylvania ssinglegreatestsourceof water pollution–Contaminated 3,000 miles of streams• Often has low pH (<5) and elevatedlevels of iron and sulfate• Can have elevated hardness• TDS typicallyaround 1,000 mg/Ly , g• Treatment is required prior to surface discharge•suitable aswith little or no treatmentButsuitableasfracwaterwithlittleornotreatmentWastewater Management is also aLimitingFactor in O&G Production• Frac FlowbackHi h fl f h t d ti–Highflowsfor shortduration– 10 to 40% of frac fluid recoveredMost recovered in first 1 to 2 weeks–Mostrecoveredinfirst1to2weeks– TDS quickly climbs to 30,000 mg/L up to 200,000 mg/L–Contains numerous chemical additives and naturallyContainsnumerouschemicaladditivesandnaturallyoccurring constituents• Produced Water– Lower flows(2 to 30 bpd per well)– Potentially very high TDS (100,000 to 300,000 mg/L)–Continues to flow for the life of the wellFrac Flowback & Produced WaterManagement Strategiesg•Evaporation in pits/ponds w/enhancementsEvaporationinpits/pondsw/enhancements• Injection/disposal wells•Discharge to POTWDischargetoPOTW• Direct reuse for drilling and fracing•Treatment for reuse or surface dischargeTreatmentforreuseorsurfacedischarge• Thermal/mechanical evaporationE ti /di till ti f f di h•Evaporation/distillationfor reuse or surfacedischargeEvaporation (from ponds)• Natural pond evaporation not practical40 i /i& 30 i /–>n/yr precp&<30in/yr evap– Poor evaporation at high salinityCrusting over–CrustingoverEvaporation (from ponds)• Use of sprayers can enhance evaporation• Potential Issues– Regulatory hurdlesS lt d iti i t l i t–Saltdeposition environmentalimpacts– Odors and VOC emissions•Ponds may still be part of management strategyPondsmaystillbepartofmanagementstrategyInjection or Disposal Wells•Significant regulatory hurdlesSignificantregulatoryhurdles– Impacts to water supply aquifers–Potential for injected water to migrate to streamsPotentialforinjectedwatertomigratetostreams• Limited capacities (1200 to 3000 bpd)•Substantial capital investment with uncertain lifeSubstantialcapitalinvestmentwithuncertainlifespan ($1M to $2M)•Probably will only play a limited roleProbablywillonlyplayalimitedrole• No new injection wells have been permitted!Discharge to POTW• POTWs are biologicalprocesses such asplagoons, trickling filters, or activated sludge plants• Biological systems cannot handle high salinityy g y-few case studies above 35,000 mg/l• Need to understand POTW discharge limits andthe treatment processes used, flow variability• Potential for VOC emissions issues at POTW• If high TDS + flow is significant portion of POTWinfluent, this is not an option• Regulatory limitations on acceptanceDirect 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 concernsR li f h i l dditi•Recycling ofchemicaladditivesTypical Water QualitySamples of Frac Flowback and Produced Water Quality(All in mg/L)FFB GrabFFB PitProduced WaterSRWR Data Sum*TDS 64,800 44,627 222,000 38,000Chloride35 90027 096145 00031 000,,145,000,TSS 1,910 765 398Hardness 11,800 9,197 67,300 3,700Calcium 4,130 3,236 23,200 770Iron 40 12 99 80B i8021 45015 7001 030arum,,,*Includes some pit waters and drilling mud wasteTreatment & Evaporation are the OnlyViable Management Strategiesg•Evaporation in pits/ponds w/enhancementsEvaporationinpits/pondsw/enhancements• Injection/disposal wells•Discharge to POTWDischargetoPOTW• Direct reuse for drilling and fracing•Treatment for reuse or surface dischargeTreatmentforreuseorsurfacedischarge• Thermal/mechanical evaporationE ti /di till ti f f di h•Evaporation/distillationfor reuse or surfacedischargeTreatment and Evaporation TechnologiesSalinity ReductionMaximumFeed TDSEnergySalinityReductionTechnologiesMaximumFeedTDSmg/lEnergykWh/100 barrel-treatedCapacitive Deionization 5,000 20Electrodialysis Reversal (EDR) 7,000 60Electrodialysis (ED) 42,000 -ReverseOsmosis50 00015-30ReverseOsmosis,VSEP 35,000 15-30Dewvaporation 100,000 to 150,000 150-400Membrane Distillation 250,000 600-700Evaporator/Concentrator 100,000 400C t lli250 000 t 350 00010001300Crystallizer250,000to350,000-Treatment versus Evaporation/Distillation• Membranes are generally less expensivethan e aporators e en tho gh significantthanevaporators,eventhoughsignificantpretreatment is required•Therefore Salinity (NaCl) level controlsTherefore,Salinity()levelcontrolsdecision•TDS > 50 000 mg/l is not practical toTDS>50,000mg/lisnotpracticaltotreat with membranes(prefer 35,000 mg/l )Crystallizers100

r y (%)Evaporation

e r Recove75

WatLimited Recovery atHigher TDS50Total Dissolved Solids (mg/l)25,000 50,000 100,000 300,000Treatment versus Evaporation/Distillation•High TDS(>35 000 mg/L)water needs to beHighTDS(>35,000mg/L)waterneedstobeblendedif membranes are to be used•Could capture first few days offlowbackforCouldcapturefirstfewdaysofflowbacktreatment, but this creates logistical issues• Membranesgenerate a reject stream tojmanage and will need an evaporator andcrystallizer anywaySRWR Approach• Segregate trucks based on conductivity• Storage in separate ponds• Purchased property with AMD as low TDSwater 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 waterConceptual Process Flow DiagramTDS <2,000 mg/LHigh Chloride1AMDFrac WaterEARLYChemPPT/Filt.ROOWS2EARLYSTAGEFFBLow ChlorideFrac Water

RejectTDS <30,000 mg/LOWSTDS >30,000 mg/L3LATESTAGEFFB & PWChemPPT/Filt.Evap&Distill.Fresh Water

SlurryCrystallizerSaltSRWR Approach (cont’d)• Focus on consistent water quality• Require operators to take water back• Minimize surface discharge–Wasting a resource– Very stringent discharge limitsSRWR Discharge LimitsParameter Effluent Limit DetectionLimitUnitsTDS 500 mg/LChloride 250 mg/LTSS ND 4 mg/LBOD(methanol concern)8.35 mg/LO&G ND 1.4 mg/LPhenolsND0 002mg/L.Naphthalene 0.053 mg/LAluminumND0 003mg/L.Strontium ND 0.0003 mg/LBoron 1.99 mg/LBenzene 0.001 mg/LIron ND 0.001 mg/LDoes Blending Make $ense?•Is it less expensive to treat AMD separatelyIsitlessexpensivetotreatAMDseparatelyfrom FFB and PW?OR$80.0$60.0$70.0$50.0

llions n d O&M$40.0

Cost in $Mi e d Capital a nEvapChem pptRO$20.0$30.0

Annual Amortiz e$10.0$0.0123Basis 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 andNo ROAll to RO$20.0$30.0

Cost Amortized$0 0$10.0$0.0$1.50/bbl $2.50/bbl $5.00/bbl $7.00/bblEvaporation Unit CostFFB and PW Have High Fouling Potential• Reversible fouling– Particulate, scale, or slimeTemperature pH adjustment• Biofouling– Slime–Temperature,pHadjustment,surfactants• InorganicC l i b i i ili– Biocide/high pH, temperature• Irreversible fouling–Cleaning study–Calcium,barium,iron, silica,strontium– Low pH, temperatureO i–Cleaningstudy• Temperature drop in process– Reduces solubility•Organic– Dissolved organic carbon– High pH, temperature– Solidification of paraffin– Particulate and paraffin foulingOperationalOperational Parameters and Conditions forParameters and Conditions forDesalination MembranesDesalinationMembranesParameter Nanofiltration Reverse OsmosisMax. Feed Pressure 600 psi 1,500 psiMax. TDS - 50,000 mg/lWater Recovery7590%4080%WaterRecovery--Solid Phase Mitigation Strategy and OperatingLimitationsCli C b tD H LSI2 53 2CalciumCarbonateDepress pH,LSI<.-.Calcium Sulfate Antiscalant,Ω< 2-400Strontium Sulfate Antiscalant,Ω< 43-50Barium Sulfate Antiscalant,Ω< 50Calcium Fluoride Antiscalant,Ω< 16,000IronAntiscalant,<8ppmFeAntiscalant,Silica: Reactive NonreactiveAntiscalant, < 120 ppmMulti-Stage Pretreatment Required• Gross oil and solids removal• Softening• Particulate removal– Coagulation, sedimentation, media filters, MF/UF• Ion exchange• Organics reduction vs control of fouling• Degasification for CO2reduction• Acid addition•AntiscalantsOngoing Issues•Pretreatment to control fouling/scalingPretreatmenttocontrolfouling/scaling• RadionuclidesVOCs•• Residuals managementE i ti i fl t b i il•Economics overtime asinfluentbecomes primarilyproduced waterSomerset in Summary• Filling a need for centralized water managementfacilities for O&G industryT i f ll i•Treating two sources ofpollution• Reduce overall treatment costs by blending• Generating an alternative fresh water source• Reduce O&G industry’s need to use surface water• Can recover some minerals• Minimize amount of wastes for disposalThank You!ThankYou!