Novel Low Fouling Nanofiltration Membranes Craig Bartels, PhD ...

Commercial Use of Nanofiltration37 mgd Mery sur Oise NF Plant (Desal 192 (2006) 303–314)Organic RemovalTDS PassagePesticide RemovalPartial Ca Removal9 mgd Boynton Beach NF Plant (AMTA 2005)Partial Ca Removal7 mgd Irvine Ranch Deep Aquafer2

New Nanofiltration Application Trends• Larger Plant Sizes: 10 – 40 mgd• Specific Permeate Hardness Target• High Organic Levels = High FoulingPotential• Disinfection By-Products Limits• Low Pressure Operation• Timing of Execution3

New Low Fouling NF Membraneswith Variable Hardness RejectionControlled hardness removal - eliminating the need forhybrid membrane designs (LF, LF2, LF3 versions)Significantly reduces operating costs by lowering powerconsumption, while providing a non-aggressive low TDSpermeate waterGreatly reduces fouling potential caused from naturalorganic matterLowest cost per gallon produced – feed pressures of lessthan 100 psi saves energy cost4

Membrane Surface PropertiesSmooth TopographyESNA1-LF Surface• Surface roughness hasbeen decreased tominimize sites for debristrappingESPA3 Surface5

Membrane Surface Properties:Reduced Surface Charge100-10ζ Potential-20-30-40ESNA1-LFESNA1LFC1Surface charge similar to LFC1-502 3 4 5 6 7 8 9 10pH• Lower surface charge minimizes interaction with surfactants6

ESNA1-LF Salt Rejection(Surface water @ 13 gfd, 25 C)100.0%97.9%99.4%98.5%96.2% 96.4%95.0%Rejection (%)90.0%85.0%83.8%89.9%85.6%80.0%75.0%Na Ca Mg Fe Cl SO4 SiO2 TOCFeed Component Type7

ESNA1-LF2: Salt Rejection(Surface Water @ 13 gfd, 25 C)100%97.9%95%93.5%95.0%92.5%Rejection (%)90%85%83.0%80%77.2%75%Na Ca Fe Cl HCO3 SO4Ion8

Typical Florida Feed Waters10

Boca Raton Water Samples11

Deerfield Treatment ProcessHolding TankWell5 um Cart Filters 769 gpm 322 gpmWaste2145 gpm 1375 gpm 447 gpmProductAntiscalantWater25 C Acid RO System 1823 gpm482 ppm TDS ESNA1-LF Total250 ppm Hardness 85% Recovery 10.5 mgd285 ppm HCO3 5 Trains, 2 Stages1.5 ppm Fe 48 Vess x 24 Vess x 7 Elem20 ppm TOC 13 gfd Flux13

City of Deerfield Beach, FL14RO System Design:10.5 MGD of PermeateESNA1-LF Membrane5 trains48-24 array of 7M tubes85% recovery13.0 gfd.Pretreatment:AcidAntiscalantCartridge filtration.Operation:Start-up November 2003Steady PerformanceNo cleaning in two years

Deerfield Beach Separation Objective15

Deerfield Plant DataESNA1-LF Performance Trend* Estimated from Conductivity16

3/24/0612.0011.0010.009.008.007.006.005.004.003.002.001.000.00Deerfield Plant DataESNA1-LF Performance TrendSalt PassageSkid 1 Stage 1Normalized DataESNA1-LF Train 13/19/045/2/046/25/048/21/0410/26/0412/1/041/7/052/8/053/11/054/13/055/12/056/14/057/22/059/1/0510/22/0512/28/052/21/061712/03/03%

3/24/06Deerfield Plant DataESNA1-LF Performance Trend12.0011.0010.009.008.007.006.005.004.003.002.001.000.00Salt PassageSkid 1 Stage 2ESNA1-LFNormalized DataTrain 112/03/033/19/045/2/046/25/048/21/0410/27/0412/1/041/7/052/8/053/11/054/13/055/12/056/14/057/22/059/1/0510/22/0512/28/052/21/06Day18%

3/24/06Deerfield Plant DataESNA1-LF Performance TrendPerm FlowSkid 1 Stage 1Normalized DataESNA1-LF Train 11400.001200.001000.00800.00600.00400.00200.000.0012/03/033/19/045/2/046/25/048/21/0410/26/0412/1/041/7/052/8/053/11/054/13/055/12/056/14/057/22/059/1/0510/22/0512/28/052/21/0619gpm

3/24/06700650600550500450400350300250200150100500Deerfield Plant DataESNA1-LF Performance TrendPerm FlowSkid 1 Stage 2ESNA1-LFNormalized DataTrain 13/19/045/2/046/25/048/21/0410/27/0412/1/041/7/052/8/053/11/054/13/055/12/056/14/057/22/059/1/0510/22/0512/28/052/21/06Day2012/03/03gpm

3/24/0650.0045.0040.0035.0030.0025.0020.0015.0010.00Deerfield Plant DataESNA1-LF Performance TrendDifferential Pres.Skid 1 Stage 1Normalized DataESNA1-LF Train 15/2/046/25/048/21/0410/26/0412/1/041/7/052/8/053/11/054/13/055/12/056/14/057/22/059/1/0510/22/0512/28/052/21/06Day2112/03/033/19/04psi

Boca Raton Treatment ProcessHolding TankWellMediaFilter5 um Cart Filters 1136 gpm 450 gpmWasteLSI = 1.93003 gpm 1867 gpm 686 gpmProductWater25 C RO System 2553 gpm466 ppm TDS No Antiscalant ESNA1-LF2 Total265 ppm Hardness NO Acid 85% Recovery 40 mgd265 ppm HCO3 10 Trains, 2 Stages0.3 ppm Fe 72 Vess x 36 Vess x 7 Elem12 ppm TOC 12.2 gfd Flux22

City of Boca Raton, FLRO System DesignESNA1-LF2 (93% hrdnss rej)36.8 MGD permeate10 1 st /2 nd Stage Trains72-36 array of 7M tubes85% recovery12.2 gfdESNA-LF3 (98% hrdnss rej)3.2 MGD permeate2 each 3 rd Stage Trains36-18 array of 7M tubes50% recovery10.7 gfdPretreatmentMulti-mediafiltersCartridge filtersNo antiscalantNo acid addition23

Boca Raton Separation Objective24

Boca Raton Plant DataESNA1-LF2/3 Performance TrendSalt PassageBoca Raton Unit 7 Stage 120Normalized Salt Passage (%)%1816141210864209-Nov-04 17-Feb-05 28-May-05 5-Sep-05 14-Dec-05 24-Mar-06 2-Jul-06Date25

Boca Raton Plant DataESNA1-LF2/3 Performance TrendSalt PassageBoca Raton Unit 7 Stage 224Normalized Salt Passage (%)%2118151296309-Nov-04 17-Feb-05 28-May-05 5-Sep-05 14-Dec-05 24-Mar-06 2-Jul-06Date26

Boca Raton Plant DataESNA1-LF2/3 Performance TrendPerm Flow Norm.Boca Raton Unit 7 Stage 1Normalized System Flow (gpm)gpm26002400220020001800160014001200100080060040020009-Nov-04 17-Feb-05 28-May-05 5-Sep-05 14-Dec-05 24-Mar-06 2-Jul-06Date27

Boca Raton Plant DataESNA1-LF2/3 Performance TrendPerm Flow Norm.Boca Raton Unit 7 Stage 2Normalized System gpm Flow (gpm)5505004504003503002502001501005009-Nov-04 17-Feb-05 28-May-05 5-Sep-05 14-Dec-05 24-Mar-06 2-Jul-06Date28

Boca Raton Plant DataESNA1-LF2/3 Performance TrendDifferential Pres. Norm.Boca Raton Unit 7 Stage 140Normalized Press Drop (psi)psi38363432302826242220189-Nov-04 17-Feb-05 28-May-05 5-Sep-05 14-Dec-05 24-Mar-06 2-Jul-06Date29

Boca Raton Plant DataESNA1-LF2/3 Performance TrendDifferential Pres. Norm.Boca Raton Unit 7 Stage 226Normalized Press psi Drop (psi)24222018161412109-Nov-04 17-Feb-05 28-May-05 5-Sep-05 14-Dec-05 24-Mar-06 2-Jul-06Date30

Analysis of Fouled Membranefrom Lead ElementEDAX of MembraneSurface covered withfoulant.SEM of MembraneSurface covered withfoulant. 3000XIonCaPOFeSiCNAtomic %8.25.929.80.80.3242.78.7Ca3(PO4)28.25.52231

Boca Raton Plant DataPerformance Results32

Conclusions• Novel NF membrane chemistry allowscontrolled variation of the hardnessrejection• Modification of the surface results in asmoother, less charged surface whichreduces fouling• High rejection of NOM materialsresults in low disinfection by-productsand meets Federal standards33