CarolloPaperTemplateWithLogo.pptx/ Affordable Desalination Collaboration Findings Related to Regulatory Criteria, Process and Costs for Seawater Desalination Tom Seacord, P.E. ADC – Chairman of the Board of Directors

CarolloPaperTemplateWithLogo.pptx/ 2 Goals of the ADC 1.Demonstrate affordable desalination using innovative technologies & processes 2.Create a body of data that can guide & benefit future designs 3.Educate the public to show that desalination is an affordable, viable source of fresh water

CarolloPaperTemplateWithLogo.pptx/ 3 Current and past members of the ADC have included agencies, consultants, and leading manufacturers West Basin municipal water district Zenon AMIAD

CarolloPaperTemplateWithLogo.pptx/ 4 ADC’s work has included three different phases 1.ADC 1: Demonstrating actual SWRO energy using conventional pretreatment and full-scale commercial technology (May April 2006) –Funded by ADC members 2.ADC 2: Further demonstration using alternate pretreatment and RO membranes (Jan - Nov 2009) –Funded by Prop 50 and ADC members 3.ADC 3: Brackish RO concepts –Collier County, FL (June – Dec 2006) –Funded by TWDB and ADC members (Feb - Dec 2010)

CarolloPaperTemplateWithLogo.pptx/ 5 ADC has proven that SWRO’s efficiency has improved significantly using off-the-shelf technology ADC 2006 Specific Power (kW-hr/AF) Specific Power (kW - hr/ kgal ) Specific Power (kW - hr/m 3 )

CarolloPaperTemplateWithLogo.pptx/ 6 ADC’s work has been widely referenced when defending desalination as a water supply alternative in California State Project WaterColorado Aqueduct WaterSWRO Specific Power (kW-hr/AF) Specific Power (kW - hr/ kgal ) Specific Power (kW - hr/m 3 ) General Perception Expert's Perception ADC 2006 SWRO Process

CarolloPaperTemplateWithLogo.pptx/ 7 Background California Water Supply & Treatment Costs ADC 2006 Expert Perception Public Perception $0 $200 $400 $600 $800 $1,000 $1,200 State Project Water Colorado Aqueduct Water Metropolitan Water District Recycled RO Seawater RO Supply & Treatment Cost ($/AF) Prod. & Dist. Cost Brine Disposal From Inland Empire Area $0 $0.6 $1.2 $1.8 $2.4 $3.0 $3.6 $0 $0.6 $1.2 $1.8 $2.4 $3.0 $3.6 $0 $0.1 $0.3 $0.4 $0.6 $0.8 $0.9 $0 $0.1 $0.3 $0.4 $0.6 $0.8 $0.9 Supply & Treatment Cost ($/ kgal ) Supply & Treatment Cost ($/m 3 )

CarolloPaperTemplateWithLogo.pptx/ 8 ADC 1 & ADC 2 US Navy Test Facility - Port Heuneme, CA

CarolloPaperTemplateWithLogo.pptx/ 9 ADC’s SWRO Demonstration Plant

CarolloPaperTemplateWithLogo.pptx/ 10 ADC SWRO Plant Schematic HP Pump PX Boost Pump PX 3 x 7 element 8” RO vessels Multi-Media Filter Supply Pump Micron Filter Seawater 1.8 kWh/m3 6.8 kWh/kgal Seawater Return 40 Foot Containerized m3/day SWRO Pilot AB C D E F G H Stream ABCDEFGH GPM PSI TDS34k 35k 10366k65k ROSA6.0 Projections SW30XLE-400, 7.2 gfd, 45% recovery, 60°F, 34,432 TDS feed, 0.85 Fouling Typical ADC Operating Conditions Holding Tank Intake pier Product Reject

CarolloPaperTemplateWithLogo.pptx/ 11 Testing Protocol

CarolloPaperTemplateWithLogo.pptx/ 12 Test Parameters & Data Collection Variables –Flux rates: 6, 7.5, 9 gfd –Recovery: 35, 42.5, 50% –Membrane Rejection: 99.5%-99.8% –Plant size: 10, 50 MGD Data analysis –Power consumption –Feed pressure and membrane DP –ASTM normalized data –Feed quality –Permeate quality and Boron –NPV of capital costs vs. O&M (energy costs)

CarolloPaperTemplateWithLogo.pptx/ 13 Cost Estimating Procedures Net Present Value Analysis –Amortized capital costs Project Life 30 years, 5% interest Co-location –10 MGD: Co-located with WWTP outfall, new open intake –50 MGD: Co-located intake/outfall with power plant –Annual O&M Power $0.08/kW-hr Replacement of Membranes (CARR) –To maintain performance (energy & permeate quality)

CarolloPaperTemplateWithLogo.pptx/ MGD Conceptual Study

CarolloPaperTemplateWithLogo.pptx/ MGD Conceptual Study Pressure Center Pump Center Energy Recovery Center

CarolloPaperTemplateWithLogo.pptx/ MGD Conceptual Study

CarolloPaperTemplateWithLogo.pptx/ MGD Conceptual Study Dedicated Pumps/ERDs Feed pump for every train Energy recovery for every train

CarolloPaperTemplateWithLogo.pptx/ 18 Test Results

CarolloPaperTemplateWithLogo.pptx/ Run Time (hours) Turbidity (NTU) Silt Density Index Raw Turb RO Feed Turb SDI Pretreatment Initial Filtration Problems –Red tide SDI < 5 –Not exceeded 86% Turbidity < 0.1 –Not exceeded 88%

CarolloPaperTemplateWithLogo.pptx/ Train Size (MGD) Specific Power (kW-hr/kgal) SW30HR-380, 6 50% SW30XLE-400i, 9 50% SW30HR LE-400i, 6 50% Specific Power (kW-hr/m3) Impact of Feed Pump - Scalability PD Pump Selected for ADC –High efficiency –Pulsating flow Centrifugal Pumps Used for Larger Trains –Low efficiency for small pumps –Smooth flow Pressure Center Design –May reduce low flow rates 50 MGD Case Study –5.9 to 8.9 kWh/kgal 10 MGD Case Study –6.6 to 9.8 kWh/kgal

CarolloPaperTemplateWithLogo.pptx/ %43%50% Recovery SW30XLE-400i Permeate Boron (mg/L) 6 GFD 7.5 GFD 9 GFD Boron < 1.45 mg/L to comply with California standard Permeate Quality - Boron Flux  = Boron  Recovery  = Boron  Low energy membrane produced marginally acceptable boron –SW30HR to 0.85 mg/L –SW30XLE-400i 1.05 to 1.44 mg/L –SW30HR LE-400i 0.45 to 0.85 mg/L

CarolloPaperTemplateWithLogo.pptx/ Permeate Quality - Boron %43%50% Recovery SW30HR-380 Permeate Boron (mg/L) 6 GFD 7.5 GFD 9 GFD Boron < 1.45 mg/L to comply with California standard

CarolloPaperTemplateWithLogo.pptx/ %43%50% Recovery SW30XLE-400i Permeate TDS (mg/L) 6 GFD 7.5 GFD 9 GFD Permeate Quality - TDS Flux  = TDS  Recovery  = TDS  Low energy membrane produced highest TDS –SW30HR to 175 mg/L –SW30XLE-400i 190 to 350 mg/L –SW30HR LE-400i 95 to 295 mg/L

CarolloPaperTemplateWithLogo.pptx/ Permeate Quality - TDS %43%50% Recovery SW30HR LE-400i Permeate TDS (mg/L) 6 GFD 7.5 GFD 9 GFD %43%50% Recovery SW30HR-380 Permeate TDS (mg/L) 6 GFD 7.5 GFD 9 GFD

CarolloPaperTemplateWithLogo.pptx/ 25 Treatment Costs Estimated Costs for 50-MGD SWRO WTP (SW30HR-380)

CarolloPaperTemplateWithLogo.pptx/ 26 Treatment Costs Estimated Costs for 10-MGD SWRO WTP (SW30HR-380)

CarolloPaperTemplateWithLogo.pptx/ 27 Summary

CarolloPaperTemplateWithLogo.pptx/ 28 Conclusions Flux & recovery impact permeate quality Low energy SWRO membrane has lowest cost, but poorest permeate quality Due to size and type of pump, 10 MGD plant less efficient –10 MGD – 6.6 to 9.8 kWh/kgal –50 MGD – 5.9 to 8.9 kWh/kgal ADC’s design  power by –10 MGD – approx. 30% over industry perception –50 MGD – approx. 40% over industry perception –Low = 5.98 kW-hr/kgal

CarolloPaperTemplateWithLogo.pptx/ 29 Conclusions (cont.) Recovery of 50% resulted in lowest NPV Improving boron/TDS rejection results in higher energy use & treatment cost SWRO is competitive with other supply options in California –10 MGD $1,552 to $1,820/AF –50 MGD $794 to $966/AF

CarolloPaperTemplateWithLogo.pptx/ 30 Recommendations Data must be taken in context of raw water quality (i.e., temperature) Designers must consider public values when establishing design water quality (i.e., boron) Future Work –Pretreatment –Higher Recovery –Long Term Testing –Economy of Scale – Large Diameter Elements

CarolloPaperTemplateWithLogo.pptx/ 31 ADC’s Publications & Outreach 1.Seacord, et al Affordable Desalination Collaboration 2005 Results. Desalination & Water Reuse Quarterly. Vol. 16:2. 2.Seacord, et al ADC 10 MGD Case Study. Proc AMTA Annual Conf. 3.MacHarg, et al ADC Baselines SWRO Performance. Desalination & Water Reuse Quarterly. Vol. 18:2. 4.Dundorf, et al Optimizing Lower Energy Seawater Desalination. Proc IDA World Congress. 5.AMTA Preconference Workshops –2008, 2009, 2011