DesalinationPresentation

DesalinationPresentation

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  Desalination Overview What AreOur Options? Arizona Water Initiative Desalination Committee Meeting September 20, 2016 Zacary Richards
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  2 Discussion Topics Current &Potential Saline Water Projects Current & Potential Ocean Water Projects
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  3 Current Saline WaterProjects What Has Been Done?
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  Current Saline WaterProjects What Has Been Done? 4 Scottsdale Water Campus Advanced Water Treatment Facility  Began production in 1999  The RO system capacity increased from 13.8 MGD to 20 MGD using a large-diameter (16 in.) RO system to save space.  20 MGD of ultrapure recycled water for use in blending with CAP water and effluent for both groundwater recharge and golf course irrigation  Addresses contaminant removal, including N- nitrosodimethylamine (chlorination byproduct) and other unregulated compounds, using a combination of ozonation, chloramination, and ultraviolet (UV) technology.  Brine concentrate is discharged into the 91st Avenue Wastewater Treatment Plant
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  5 Current Saline WaterProjects What Has Been Done? Goodyear Reverse Osmosis (RO) Facility  Centerra Well contains 1,900 mg/L of Total Dissolved Solvents (TDS) and 17.9 mg/L of Nitrate  3.2 MGD of brackish water is sent from the well to the RO Facility  Facility treats 2.7 MG of well water and provides 2 mg of clean drinking water which is mixed with .5 MG of brackish water  The .7 MG of brine concentrate (7,447 mg/L TDS) is mixed with wastewater, cleaned to an A+ quality at the 157th Ave water reclamation plant, and stored underground  Capital Cost: $1.98M  Operating Cost: $0.93/kgal
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  6 Current Saline WaterProjects What Has Been Done? Bullard Water Campus  A permanent facility to replace the emergency facility in Goodyear  Water capacity of approximately 5 MGD and began operation in early 2008  15,500 square foot prefabricated building including:  Eight RO skids  Sulfuric acid chemical treatment system  Threshold inhibitor system  Caustic soda chemical treatment system  Chlorine system  Clean in place system  Sewer discharge tank  SCADA operating and monitoring system, and site enhancements Capital Cost: $10,789,745
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  Current Saline WaterProjects What Has Been Done? 7 Bullard Water Campus  Wetlands brine treatment would reduce the volume of salt entering the 157th Ave water reclamation facility.  This will lower the salt content in reclaimed water. More landscaped facilities may be willing to use reclaimed water with lower salt content.  Lower salt content would reduce facility operating costs through improved efficiency.  Wetlands brine treatment will save energy.  Wetlands brine treatment would require less energy than other disposal alternatives for brine.
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  Methods of BrineDisposal 8*million gallons per day Central Arizona Salinity Study 2010
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  Current Saline WaterProjects What Has Been Done? 9 Yuma Desalting Plant (YDP)  Completed in 1992 to treat saline agricultural drainage from the Wellton- Mohawk Irrigation District until it became dormant  Bureau of Reclamation conducted a year- long pilot test from May 2010 to March 2011 and treated 30,496 acre-feet of drainage water (~27.2 MGD) at 1/3 of the plant’s capacity  Power Consumption: 37,541 MWh with an average price of $32.68 per MWh  82% efficiency if operated at 430 psi, but higher power costs  Produced water had an average salt concentration of 252 mg/L TDS Final Pilot Run Report Reclamation, 2012
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  Current Saline WaterProjects What Has Been Done? 10 Yuma Desalting Plant (YDP) Trial Costs *lower than expected costs for power, labor, chemicals and materials Final Pilot Run Report Reclamation, 2012
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  Future Brackish WaterProjects What Can We Do? 11 Final Pilot Run Report Reclamation, 2012
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  Future Saline WaterProjects What Can We Do? 12 Yuma Brackish Groundwater Treatment of Yuma Mesa  USGS estimates 600,000 to 800,000 acre-feet of brackish groundwater  Estimated yield: 40,000 AFY  Capital Cost: $132M  Annual O&M: $1.7M  Implementation: 7-9 yrs Black & Veatch 2014 Yuma Desalination Plant Well Field
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  Future Saline WaterProjects What Can We Do? 13 Navajo/Hopi Planning Area  Saline groundwater due to bedded salt in sedimentary formations  Little Colorado and Eight Lakes in the PA have impaired water quality due to levels of turbidity, lead, copper, mercury and silver in excess of use standards  Municipalities are projected to consume 23,093 acre feet per year by 2035 Phoenix AMA Basin  A 35 mile long brackish water supply exists on the Gila River between its confluence with the Salt River to the outfall of the Basin at Gillispie Dam
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  Future Saline WaterProjects What Can We Do? 14
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  Future Saline WaterProjects What Can We Do? 15 Desalination in California Imperial Valley Drain Water Treatment  Yield = 200,000 AFY increments  Capital Cost = $2.25B  Annual O&M = $77M  Unit Cost = $1,000/AF  Implementation = ~ 15 years Black & Veatch 2014 Coachella Valley Drain Water Treatment  Yield = 101,000 AFY  Capital Cost = $395M  Annual O&M = $30M  Unit Cost = $500/AF  Implementation = ~15 years Key Factors: • Dust Control • Reduced Flows to Salton Sea • Migratory Bird Impacts
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  Current Ocean WaterProjects What Has Been Done? 16 Carlsbad Desalination Plant  2,000 pressure vessels with 8 RO membranes in each vessel  Draws 100 MGD of ocean water and produces 50 MGD or 7% of San Diego’s water supply (enough for 112,000 households)  Two stage pretreatment process  Microfiltration  Multimedia Filtration Tanks  Energy recovery devices recycle 46% of energy used in the RO process saving $12m annually  40MW to operate which is energy for 30,000 homes and costs $49m-$59m annually  $2000 - $2200 per acre foot or an increase of $5 - $7 on monthly water bills  Capital Cost: $734m in private bonds  15 year process
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  Future Ocean WaterProjects What Can We Do? 17 Sea of Cortez Desalination  Treated water could be conveyed via pipeline and discharged upstream of Morelos Dam  RO rejected brine would be deposited into the Sea of Cortez  Water could be delivered to Mexico in exchange for upstream storage or diversion  Estimated Yield: 200,000 to 1.3M AFY  Capital Cost: $4.5B  Annual O&M: $185M  Unit Cost: $2,200/AF  Implementation: 15 yrs Colorado River Delta Biosphere Reserve Pincate and Gran Desierto de Altar Biosphere Reserve Black & Veatch 2014
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  Things to Consider 18 MembraneUpgrades  Reducing energy costs by using graphene, which is one atom thick, instead of polyamide  Use 16 inch diameter membranes instead of 8 inch diameter – more surface area and less energy cost, however, only one manufacturer makes them Dilution Solution  Using reverse osmosis pressure retarded osmosis (RO-PRO) results in a decrease in energy by 30% http://www.pri.org/stories/2015-05-15/desalination-expensive-energy-hog-improvements-are-way
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  Things to Consider 19 http://www.pri.org/stories/2015-05-15/desalination-expensive-energy-hog-improvements-are-way Recapturingand Renewable  Turbochargers take kinetic energy from the output and reapply it to the input  Pretreating water before it goes into the membranes saves energy and the life of the membranes Environmental Concerns  RO-PRO reduces salt concentration in the discharge  Forward osmosis in smaller plants that produce no more than 26,000 gallons of water a day see a 42% reduction in energy use  Diffusers increase the volume of seawater mixing with the concentrated discharge and prevents spots on the ocean floor containing high salt levels
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  Things to Consider 20 http://www.pri.org/stories/2015-05-15/desalination-expensive-energy-hog-improvements-are-way MembraneCapacitive Deionization (MCDI)  Separates ions using electrodes  318,000 gallons per day plant in China  75% water recovery rate  1kWh for 264 gallons = $0.22
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  Questions?
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  Arizona Water Initiative Coordinator: ZacaryRichards [email protected] (602) 771-8311