WATER DESALINATIONMARTIN DEGOS (EMSE)WEI-TING SHIH (NTU)

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INTRODUCTION• DESALINATION IS A PROCESS THAT REMOVES MINERALS FROM SALINE WATER.

• SALT WATER IS DESALINATED TO PRODUCE FRESH WATER SUITABLE FOR HUMAN CONSUMPTION OR IRRIGATION.

• “AT THE MOMENT, AROUND 1% OF THE WORLD'S POPULATION ARE DEPENDENT ON DESALINATED WATER TO MEET THEIR DAILY NEEDS, BUT BY 2025, THE UN EXPECTS 14% OF THE WORLD'S POPULATION TO BE ENCOUNTERING WATER SCARCITY”

CHRISTOPHER GASSON (GLOBAL WATER INTELLIGENCE)

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WHERE ARE THEY USED?• Australia

• Many countries in the Middle East: - The single largest desalination

project is Ras Al-Khair in Saudi Arabia (1,025,000 cubic meters per day)

- Israel produces 40% of its domestic water use from seawater desalination

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METHODS

• DISTILLATION• MULTI-STAGE FLASH DISTILLATION (MSF)• MULTIPLE-EFFECT DISTILLATION (MED|ME)• VAPOR-COMPRESSION (VC)

• ION EXCHANGE• MEMBRANE PROCESSES

• ELECTRODIALYSIS REVERSAL (EDR)• REVERSE OSMOSIS (RO)• NANOFILTRATION (NF)• MEMBRANE DISTILLATION (MD)• FORWARD OSMOSIS (FO)

• FREEZING DESALINATION

• Geothermal desalination• Solar desalination

• Solar humidification-Dehumidification (HDH)

• Multiple-effect humidification (MEH)• Methane hydrate crystallization (fire

ice)• High grade water recycling• Seawater greenhouse

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MULTISTAGE FLASH DESALINATOR

Schematic of a multistage flash desalinatorA – steam inB – seawater inC – potable water outD – waste outE – steam outF – heat exchangeG – condensation collectionH – brine heater

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ION EXCHANGE

Ion exchange resin beads 6/12

REVERSE OSMOSIS

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ENERGY CONSUMPTION

Desalination Method

Multi-stage Flash

Multi-Effect Distillation

Mechanical Vapor

CompressionReverse

Osmosis(RO)

Electrical energy (kWh/m3) 4–6 1.5–2.5 7–12 3–5.5

Thermal energy (kWh/m3) 50–110 60–110 None None

Electrical equivalent of thermal energy (kWh/m3)

9.5–19.5 5–8.5 None None

Total equivalent electrical energy (kWh/m3)

13.5–25.5 6.5–11 7–12 3–5.5

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DRAWBACKS

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VIDEO

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REFERENCES

• HTTPS://EN.WIKIPEDIA.ORG/WIKI/DESALINATION• HTTPS://EN.WIKIPEDIA.ORG/WIKI/THERMOHALINE_CIRCULATION• HOW SEAWATER DESALINATION WORKS (YOUTUBE)

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THANKS FOR YOUR ATTENTIONANY QUESTIONS?

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