1. THE DESALINATION OF SEAWATER
THROUGH ELECTRODIALYSIS AND
THERMAL DISTILLATION
Melissa Guardado
Ming Suet Kwan
Brian Maynard
Pasadena City College

2. CALIFORNIA DROUGHT
As of January 14 2016: 42% of
the state is in D4 (Exceptional
Drought) status.

3. LAKE OROVILLE

4. CURRENT SOLUTIONS
1.Water Conservation
3.Water Reuse
2. Storm water Capture
4. Desalination

5. CARBON FOOTPRINT OF DESALINATION
High energy usage. Desalination requires a
substantial amount of energy input to purify water for
drinking purposes
High carbon emission. High energy usage
correlates with a greater amount of emissions released.
Carbon emissions are commonly associated with the
disapproval of desalination systems.
Source: http://www.pacinst.org/reports/desalination_2013/energy/

6. PROJECT SCOPE
CONSTRUCT A UNITTHAT IS:
• Efficient in desalination
• Able to treat Brackish water to fresh water
• A realistic solution to California drought

7. PV-ED UNIT

8. TREATMENT METHODS
THERMALTECHNOLOGIES
• Multistage Flash Distillation
• Multi Effect Distillation
MEMBRANETECHNOLOGIES
• Reverse Osmosis
• Electrodialysis
Thermal processes
(MSF, MED,VC)
Membrane processes
(RO)
Typical salt content of
feedwater (ppm)
30,000-100,000 1,000-45,000
Desalted water with low
total dissolved solids
concentrations (ppm)
10.0-20.0 100-550
Thermal energy
consumption (kWh/m^3)
12 0
Energy consumption
(kWh/m^3)
17-18 2.2-6.7
Recovery Factor 40-50% 40-80%
Capital costs high low
Operating costs high low
Desalted water cost
($/m3)
0.9-1.4 0.50-0.70

9. DISTILLATION SET UP AT PCC

10. WHY ELECTRODIALYSIS?
Efficiency. It is efficient and effective in
treating brackish water ranging from total
dissolved solids (TDS) of 1000-5000 mg/L.
According to the USGS, in many regions
where freshwater is lacking, there is an
abundance of brackish groundwater.
An alternative solution to provide fresh
water for barren, semi-arid, and remote
regions.
Electro Dialysis
Reversal (EDR) Plant
Barcelona, Spain
15,240 GPD

11. ELECTRODIALYSIS
ED stack
• Electrodes
• Anion and cation
permeable membrane
Flow path
• Dilute
• Concentrate
• Electrode Rinse

13. PCC ELECTRODIALYSIS DEVICE

14. PCC ED UNITTEST

15. PCC vs. CPP ED UNIT

16. DATA COMPARISON
Distillation EDS
Salinity 0.0%
(~ pure water)
0.6%
(~ red sea)
Energy used 2.00 kWh/m3 1.43 kWh/m3
Cost of
energy
$1.47/m3 $1.05/m3
• Distillation completely removed
all salts while EDS gave a very low
salinity in produced water.
• EDS uses 28.5% less energy than
Distillation
• Thus, EDS costs less.

17. Traditional desalination EDS
Energy consumption Requires more energy Requires less energy
Environmental effect • Higher emission of CO2
• Lower salinity discharged with 8-
10times inlet flow
• Lowering oxygen level by higher
temperature of discharged brine
• Additional chemicals:
- Biocide
- Scale control chemicals
- Antifoam
• Lower CO2 emission
• Higher salinity discharged with
3 times inlet flow
• Unaffected oxygen level due to
unchanging temperature
• Additional chemicals:
- Biocide
- Scale control chemicals
Sustainability ~40 years
Depending on the construction
materials
Replaceable membrane lifetime:
~20 years
Depending on membrane and
pretreatment
SIGNIFICANCE OF DATA

18. ACKNOWLEDGEMENTS
Pasadena City College
Dr.Veronica Jaramillo
Rafik Nazarpoor
Phu Nguyen
Cal Poly Pomona
Dr. Monica Palomo
Dr. Ali Sharbat
LucasTownsend
Kahao Lim
Dr. Graciela Matrajit
Brian Rucci
Kristine Schroeder
SHINE