Research and Development on Solar Thermal Water Desalination by eyq18884

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									    Research and Development on Solar Thermal Water Desalination

Aliakbar Akbarzadeh, John Andrews, Yuchun Zhao, Jimmy Leblanc and Fulaqi Bai
            Energy Conservation and Renewable Energy (CARE) Group

         School of Aerospace, Mechanical and Manufacturing Engineering,




                            SET Research Ideas Day
                              14 November, 2008
Salinity crisis

• The rise of the salty water table in many areas of Australia including northern
  Victoria is threatening a large area of agricultural land
• Rising salinity levels ruining 2.5 million hectares of land and resulting in lost
  agricultural production worth more than A$130 million annually (NAP, 2001)
• Mainly caused by tree clearing and extension of irrigated agriculture
• Mismatch between the water going into the ground and the water coming out
  of the ground, leading to a rise in the watertable and salt concentrations in the
  soil
    Costs of water


• Distilled water:   $1.4-1.6/litre
• Bottled spring water: ~$0.43-2.30/litre
• Domestic/industrial water price: ~$0.8-1.4/kilolitre
• Irrigation water (market trading rate): $1/kilolitre
• Recycled water: cost 1/3 to ¾ price of potable water price (Yarra Valley
  Water)
Reverse Osmosis




• Seawater: High Pressure Feed Pump 60 – 90 bar (Recovery ratio:
  30 – 50 %)
• Brackish water: 5 – 30 bar (Recovery ratio: 70 – 80%)
• TDS of single-pass SWRO system: < 500 ppm
• TDS of second-pass SWRO system: < 50 ppm
• Membrane lifetime: + 5 yrs
Desalination plant in Perth

• First seawater desalination plant officially opened on 19
  November 2006
• Reverse osmosis plant at Kwinana industrial complex to
  supply 17% of Perth’s drinking water (130 ML/day, 47
  GL/y)
• Capital cost $387 million
• Annual running cost <$20 million
• 24 MW power demand, 185 GWh/year
Wonthaggi Desalination Plant Proposal



      VIC Government plan (2007):
      • Desalinate seawater to produce fresh water for Melbourne


      • Build Reverse osmosis plant at Wonthaggi.


      • Power by grid electricity (but Greenhouse offset by purchase of Renewable
        energy)


      • Capable of supplying 450 megalitres of drinking water per day (~150 GL/year
        with 10% downtime), a third of Melbourne's water needs


      • Capital Cost: $3.1 billion plant


      • Annual Operating Cost: $130 million


      • Planned to come on-line by the end of 2011
Solar Pond – Multi-Stage Flash (Once-through)




 Vaporises incoming heated brine in evacuated vessels at progressively lower
 temperatures. Water vapour is condensed to fresh liquid water by the incoming
 brine to provide the preheating.
 Experimental Multi-Effect Evaporation Solar-Thermal
             Desalination unit (MEE-3E)




- Daily distillate production of ~ 2,000 litres (~ 0.73 ML / year).
- Recovery ratio ~ 52% with a specific thermal energy ~ 970 kJ/kg.
- Requires ~ 800 m2 solar pond (Melbourne insolation).
Combined Desalination and Power Generation
Combined Desalination and Power (CDP)
Combined Desalination and Power (CDP) Generation

								
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