DESALINATION AS AN ALTERATIVE WATER SUPPLY

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1 DESALINATION AS AN ALTERATIVE WATER SUPPLY 7 th Annual Georgia Environmental Conference, Water Management Practices and Georgia s Adopted Regional Water Plans, Session 5, Course 41 August 22-24, 2012 Chandra Mysore, Ph.D., PE, BCEE National Practice Leader Water: GHD

2 Presentation Overview Background Drivers of Desalination Challenges to Desalination Desalination Worldwide Australia-The Big Six Desalination in the US Conclusions

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4 Major Commercial Processes Distillation Processes Multi-Stage Flash (MSF) Multiple Effect Evaporation (MEE) Thermal or mechanical vapor compression (VC) Membrane Processes Nanofiltration, Reverse Osmosis (RO/SWRO) Electrodialysis Reversal (EDR)

5 Membrane Processes SCANNING ELECTRON MICROSCOPE OPTICAL MICROSCOPE VISIBLE TO NAKED EYE MICRON IONS MOLECULES MACRO MOLECULES MICRO PARTICLES MACRO PARTICLES Angström Molecular weight Sugars Dissolved salts Pesticides Viruses Bacteria Algae and protozoans Metal ions Colloids Sands Humic acids REVERSE OSMOSIS MICROFILTRATION NANOFILTRATION WEFTEC 2008 Note : 1 Angström = meter = 10-4 micron ULTRAFILTRATION CONVENTIONAL FILTRATION

6 Desalination History Aristotle described distillation BC Distillation: Desalination on early ships - 200AD Distillation: MED (Norbert Rillieux, ) Coolgardie Water Distillery (WA) Distillation: Desalination MSF Distillation: Desalination MED Distillation: Desalination MVC, METC 1960 Membrane: RO (Drs. Sourirajan & UCLA, 1959) Membrane: RO (John Cadotte - FilmTec, 1970) Membrane: Desalination RO and NF Membrane: Pre-treatment (MF, UF) Membrane: Wastewater (MBR) Dr. Sid Loeb

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9 DRIVERS OF DESALINATION Advances in RO Membrane Technology Greater salt rejection, Higher fluxes, Better fouling resistance Advances in system design, Larger diameter modules Lower Costs Improvements in membrane pre-treatment Conventional (SDI= 2-3.5); MF/UF (SDI < 2.0) Energy Cost Reduction Energy Recovery Devices; Low Pressure SW and BWRO Warmer Power Plant Water as Feed Source

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11 DRIVERS OF DESALINATION Trend towards co-location with power plants Advantages Existing ocean intake and discharge pipelines Warm water feed from cooling tower blowdown Coastal property access Reduces infrastructure, energy costs Minimizes SWRO plant size Dilution of concentrate stream Favourable power rates

12 CHALLENGES TO IMPLEMENTING DESALINATION Environmental Regulatory Water Quality Concentrate Disposal Membrane Fouling Post-treatment, Corrosion Public Perception Industry Conservatism Costs Particulates Biofilm Organics Scale Scanning Electron Micrographs

13 CONCENTRATE DISPOSAL

14 The Big Australia s six big desalination plants

15 Plant Capacity (mgd) Status Dist Pipeline (miles) Ave annual rainfall (in) 1 Sydney 66 Operating Gold Coast 33 Operating Perth I (Kwinana) 33 Operating Victoria 107 Under const Adelaide 36 Under const Perth II (Binningup) 33 Under const

16 The Seawater Reverse Osmosis (SWRO) Desalination Process

17 Perth s Water Crisis The West Australian Saturday 27 November 2010

18 The Big Six No. 1 Perth Seawater Desalination Plant (Perth I) - 38 mgd Client: Water Corporation Capacity: 38 mgd Plant Capital Cost: $266 million Connecting System (IWSS): $51 million Total Capital Cost: $317 million Total Operating Cost: $16 million/year Unit Cost: $1,172/AF (AU$1.00/m 3 ) Commissioning Completion: 2007 GHD Involvement: Production of Basis of Design and Basis of Construction Documents, 3 rd Party Review of Designs from both Competing Consortia, Durability Reviews During Design and Construction Phase, Integration Network Concept and Detailed Design including the largest Pumping Station in the Perth Integrated System, the Nicholson Road Pumping Station (10 MW). Seaglider Oceanographic Measurements Configuration: Open Intake, Diffuser Outfall, Travelling Band Screens, Dual Media Pressure Filtration, 5 Micron Cartridge Filtration, 2 Pass SWRO System, Lime and CO 2 Re-mineralisation Seawater Feed Quality: mg/l TDS Product Water Quality: < 200 mg/l Specific Energy Consumption (SEC): < (13.18) kwh/kgal (3.48) kwh/m 3 ) Technology Contractor: Degremont (France/Spain) Awards: GWI Membrane Desalination Plant of Year 2006 ERI Awarded GWI Environmental Contribution of the Year 2006

19 Potable water pump station HV substation Remineralisation/ Storage Chemical Storage Raw Seawater screen and pump station Aerial View of Desalination Plant Admin /Lab SWRO & BWRO Residuals Treatment Brine discharge Pretreatment Seawater Intake Brine discharge Courtesy of Water Corporation

20 Seawater Desalination Initiative in the US Utility/Corp. Location Capacity (MGD) Tampa Bay Water San Diego County Water Authority Poseidon Resources LADWP West Basin Orange County Cost ($/Kgal) Tampa, FL Carlsbad, CA 50* 2.75 Huntington Beach, CA Los Angeles, CA El Segundo, CA Dana Point, CA 50*

21 Brackish Water Desalination in the US Utility/Corp. Location Capacity (MGD) City of North Miami Beach, FL Aquaria Water/City of Brocton Town of Jupiter City of Simi Valley City of Sherman Hilton Head North Miami Beach, FL (Norwood WTP) Process 17 to 32 9 MGD NF (Biscayne) 6 MGD RO (Floridan) Taunton, MA 5 Immersed UF + Enh. Coag. + RO Jupiter, FL 14.5 RO Simi Valley, CA 1.0 RO Sherman, TX 10 Conventional + EDR Hilton Head, SC 3 to 6 RO

22 COST STRUCTURE FOR SWRO SWRO COST STRUCTURE Electric Power 44% Fixed Charges 37% Consumables 3% Maintenance and Parts 7% Membrane Replacement 5% Labor 4%

23 Treatment cost for fresh water from a conventional water treatment plant $ /1000 gallons Imported Water from MWD, CA $1.50/1000 gallons Reclaimed water for industry in Southern California $2.22/1000 gallons Treatment cost for desalinated brackish water for residential use Treatment cost desalinated seawater Santa Barbara, CA (1992) $1-3/1000 gallons $5.50/1000 gallons Desalination Cost (2000-now) $ /1000 gallons Tampa Bay (2001) $2.40/1000 gallons Thermal Desalination $ /1000 gallons

24 FUTURE TRENDS Economy of Scale 16 Elements:-3-6X area, flow of 8 Elements Energy Recovery Devices Turbochargers Pressure Exchangers Nanotechnology Increases permeability by 75% Better rejection Energy Reduction (25%) Biocidal Properties

25 CONCLUSIONS There is no silver bullet solution to the nation s future water challenges (e.g. drought, increased salinity, ever-increasing demand). Desalination, as an alternative water supply, can meet a substantial component of US s water supply needs. The amount of energy necessary to operate desalination plants will continue to decrease as membrane efficiencies increase and newer products enter the market. Sophisticated and sustainable seawater desalination plants will be the future trend using alternative forms of energy (e.g. wind power, solar energy etc).

26 Questions? Thank you. GHD CLIENTS PEOPLE PERFORMANCE Chandra Mysore, National Practice Leader - Water Ph.D., PE, BCEE T chandra.mysore@ghd.com GHD serves the global markets of: Infrastructure Mining & Industry Defence Property & Buildings Environment