The document describes the development of an integrated power delivery electrodialysis desalination system (IPDEDS) by a team of students. The IPDEDS uses electrodialysis, a membrane process, to remove salt from brackish and ocean water in an energy efficient manner. It is powered independently by a photovoltaic cell, requiring minimal energy. The team designed and tested plastic electrodialysis cells that successfully removed salt from saltwater samples. Their goal is for the IPDEDS to benefit water-stressed coastal communities and emergency situations by providing portable, low-cost desalination.

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Development of an Integrated Power Delivery Electrodialysis Desalination System!
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VARUN SHANKER
AUSTEN ZHU
SATYAJIT SARKAR
MADISON KENT
ANDREW WONG
DOW HIGH ELECTRODIALYSIS
DESALINATION SYSTEM

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Table!of!Contents!
Executive)Summary)................................................................................................................)3!
Project)Overview)..............................................................................................................................)3!
Impact)of)External)Factors)................................................................................................................)4!
Description)of)Innovation).................................................................................................................)5!
Global)Benefit)..................................................................................................................................)6!
Statement)of)Work).................................................................................................................)7!
Wooden)Experimental)Cell)...............................................................................................................)7!
Plastic)Batch)Cell)with)Flow)..............................................................................................................)9!
Plastic)Batch)Cell)Testing)................................................................................................................)11!
Data)Analysis).................................................................................................................................)19!
Early)Prototype)of)Integrated)Power)Delivery)Electrodialysis)Desalination)System)(IPDEDS))..........)20!
Market)Plan)...................................................................................................................................)23!
Research)and)Explanation)of)Existing)Technology)..................................................................)28!
Financial)Plan)........................................................................................................................)32!
Funding)..........................................................................................................................................)34!
Project)Management)&)Timeline)...........................................................................................)38!
Graphical)Representation)......................................................................................................)39!
Appendix)A)............................................................................................................................)43!
References)............................................................................................................................)49!
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Executive!Summary!
Project!Overview!
!
As the global population continues to rise and sources of freshwater become increasingly
depleted, water purification and desalination technologies are emerging as the most prominent
method to meet this fundamental need. The most rapidly growing approach to converting
saltwater to drinkable water is reverse osmosis, a method of desalination that removes water
molecules from salt water through pressure, leaving salt ions in a residual brine. However, more
cost-effective and sustainable alternatives such as electrochemical desalination are being
developed.
Electrochemical desalination processes exhibit the greatest future potential to meet the
world’s potable water needs. An electrochemical cell (schematic shown below) is a device that
utilizes electrical energy in order to facilitate chemical reactions. This technology can be applied
more specifically to desalination through electrodialysis: a membrane process, in which ions are
transported through a selectively semi-permeable membrane, under the influence of an electric
potential. The Dow High Team utilized and created advanced technologies developed an
innovative, low-cost, efficient, energy- independent electrodialysis system functioning to
desalinate brackish and ocean water, thereby producing pure, potable water.

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Through the product development process and scientific experimentation, the Dow High
team was successfully able to design, engineer, construct, and test and prove the innovative
electrodialysis method of desalination. Product development began by machining the structure of
the construct from chemically inert polypropylene plastic and continued into assembly of the
piping, tubing, and smaller hardware components. The final construct was experimentally tested
in numerous trials to ensure statistically robust and reliable data.
The Dow High electrodialysis cell has proven to be effective at removing salt from
simulated seawater samples. The complete model development is highly scalable, requires lower
infrastructure investment than reverse osmosis and other competing technologies, and is highly
energy efficient as salt concentrations approach brackish water levels. Designed to be energy-
independent, the electrodialysis system is powered by a photovoltaic cell (solar panel).
Impact!of!External!Factors!
!
Efficiently designed electrodialysis systems have a unique comparative advantage to
alternate methods of water conversion and desalination by mitigating and minimizing the impact
of uncontrollable external factors. Unlike other methods of desalination such as distillation and
the solar still, the electrodialysis system is able to function independent of the weather and
climate conditions. The only external input required is electricity. The design of the
electrodialysis system allows for convenient interchange of power supply. Most encouragingly,
the energy required to supply the system is minimal, easily generated by photovoltaic cells, and
can be stored in a battery enabling the cell to operate at night and on cloudy days. Depending on
the area of use, the power supplying photovoltaic cells can be substituted with other sources of
alternative energy such as Peltier tiles, which function by converting thermal gradients into
electrical energy.

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! 5!
One key advantage of the electrodialysis system is its lack of dependency on the
concentration and form of salt water. It was demonstrated, without fail, through numerous trials
that the electrodialysis system performs efficiently at removing salt from ocean and brackish
water at both high and low concentrations of salt. Additionally, the Dow High team’s
electrodialysis system has a unique comparative advantage to alternate forms of water
conversion in dually functioning to kill biological organisms and pathogens that may be present
in the salt water.
Description!of!Innovation!!
The integrated power delivery electrodialysis desalination system (IPDEDS) engineered
by the Dow High team is a unique combination of advanced technologies that meets a basic need
in broad applications. The complete desalination system is the integration of an independent
power source fueled by renewable energy with a uniquely designed robust and low maintenance
electrodialysis cell, based on sound fundamental scientific principles. The electrodialysis cell,
which incorporates hybrid membrane technology, was completely machined and assembled from
stock plastic and hardware components into a reliable and compact desalination device.
Consistently shown to desalinate saltwater with concentrations similar to ocean and brackish
water (upwards of 35g/L of salt in scientific experimentations) the electrodialysis cell
incorporated in the innovative IPDEDS proved to be more robust, cost-effective and sustainable
than competing methods of water conversion. While other systems of desalination such as
reverse osmosis and distillation have been used in large scale implementations, the portable
electrodialysis system proves to be far more economical and convenient for its target markets. At
the center of this innovative the electrodialysis system lies its unique value proposition. In

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addition to offering portability and high efficiency, the system is easily scaled up in a modular
fashion, and is thereby able to increase total output at a marginal additional cost.
Global!Benefit!
! Although water scarcity can be an abstract concept, to many it is truly a stark reality– an
outcome of environmental, economic, and, geographic forces. While water constitutes 70 percent
of the world's surface, only 2.5% of it is freshwater, leaving the remainder as saline and ocean-
based. Moreover, 99% of this freshwater is in unusable forms such as snowfields and glaciers.
Simply put, 0.007% of the earth's water is accessible to meet the drastically increasing rate of
consumption of the world's seven-plus billion individuals. It is imperative to consider the
development of new water desalination technologies to accommodate the population’s needs.!
The IPDEDS is applicable to coastal communities of developing countries, military needs
and emergency situations. It is estimated that by 2025, over 1.8 billion people will be living in
water stressed regions. As a result, the independently powered electrodialysis system is capable
of providing a broad and prominent global impact. In a remote area, military troops can hydrate
themselves while traveling with the system. In coastal water stressed areas After a hurricane or
an earthquake strikes a coastal town contaminating its freshwater reserves, individuals will be
able to quickly desalinate highly concentrated saltwater to produce potable water. IPDEDS has
the potential to be a game-changing system that fulfills the need for water in such situations.
This innovative desalination system has the potential to revolutionize the water
purification and desalination industry and, in effect, provide widespread global impact benefiting
millions.!
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Statement!of!Work!
!
The team decided to focus on creating a device that could provide a reliable, modular and
portable, low cost, source of clean, sanitary water from sea water or other brackish water
sources. After initial research, the process of electrodialysis was chosen as the method of
desalination. Several intermediary goals were created. Chiefly, a robust electrodialysis cell
design was needed. Secondly, the team needed to prove that electrodialysis could be used on a
smaller, more portable scale. Finally, in order to create a product that would be relevant in
power-deprived areas, the team decided that alternative energy sources should power the
desalination process. The prototype would incorporate the electrodialysis cell design, alternative
energy resources in the form of solar panels, an organized system of piping and wiring, and a
plastic casing for portability.
Wooden!Experimental!Cell!!
!
Initially, the team decided to create a wooden batch cell. A batch cell desalinates a
“batch”, or fixed amount, of salt water until purification. In comparison, a flow cell continuously
processes and dilutes new salt water. This initial design consisted of a 8.5” x 8.5” x 9.5” cell with
an open top. 1” thick plywood was sourced from the school’s woodshop for construction, leaving
a 6.5” x 6.5” x 8.5” space for the salt water. This space was then separated into 3 chambers, each
2.166” x 6.5” x 8.5”. Along the divisions between each of these chambers, cavities were cut into
the wood to accommodate the needed membranes. In order to fix the membranes within these
cavities, a square hole of 5.5” x 5.5” would be cut from 7” x 7” plastic acrylic sheets. Two of
these frames would sandwich the 6” x 6” membrane, allowing the membrane to be exposed to
salt water through the inner opening. The space between each plastic frame-membrane construct

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was sealed with silicone sealant. The wooden joints were also sealed with the same sealant. Two
square 5” x 5” copper sheets were to be attached with epoxy onto the inside of the end pieces in
both the left and right chambers. The copper electrodes were to have a copper wire soldered onto
them to power the electrodialysis process.
For testing, these wires would have been connected to a power supply. A logger pro
voltage probe would have been attached to the two copper wires. Additionally, a salinity probe
would have been placed inside the center chamber (the product chamber).
However, as expected, a variety of issues were identified from this early prototype.
During the desalination process, dilute water is formed as a thin layer of water close to the
membranes in the product chamber. Because the water within this design does not circulate, the
water would not be homogenously desalinated thus requiring a mixing mechanism. Additionally,
because of this lack of flow within the cell, the anolyte (the portion of the electrolyte in the
immediate vicinity of the anode in an electrolytic cell)!and catholyte (the portion of the
electrolyte in the immediate vicinity of the cathode in an electrolytic cell) become extremely
concentrated with byproduct, creating a potentially potent solution. Using wood as the material
of the container also presented a major issue- it would absorb water and thus lose dimensional
Wooden&Experimental&Cell&with&Plastic&Frame&
inside&

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robustness and strength. As a result of this evaluation of the initial prototype design, the team
proceeded to design a secondary construct featuring external chambers allowing for mass
transport of solutions.
!
Plastic!Batch!Cell!with!Flow!!
!
The revised design addressed the two primary concerns: excessive volume (distance)
between the ion exchange membranes and lack of flow in all three chambers of the batch cell.
Additionally, polypropylene which is a commodity lightweight and chemically inert
thermoplastic was chosen to address the absorption issues.
Two polypropylene pieces of 7” x 7” x 1” were used as stock for the outer anolyte and
catholyte chambers. An inset square of 5.5” x 5.5” was milled out of the stock ¾” deep, resulting
in a fluid compartment (chamber) of 5.5” x 5.5” x .75”.
In order to house the membranes, four 7” x 7” rubber gaskets were used. Each rubber
gasket had a 5.5” x 5.5” square inset cut out. A 7” x 7” ionic exchange membrane was then
placed in between two rubber gaskets. This was repeated twice, once for the anionic and once for
the cationic membrane.
A polypropylene piece of 7” x 7” x ¼” was used as the inner product chamber. The same
5.5” x 5.5” square inset was cut out of this polypropylene piece.
The cell is built as a stack. Construction begins with an outer chamber. A 5” x 5”
electrode is placed within the milled cavity of this chamber. A membrane framed by two rubber
gaskets is placed on top. Next, the inner chamber is placed on the developing stack. Another
rubber gasket-membrane frame is added. Finally, the second outer chamber is added with a 5” x
5” electrode, finishing the stack.

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Coincident holes were punched into the membranes, the chambers, and the rubber
gaskets. In order to fix the stack together, it was compressed with a combination of screws and
washers. Using a drill press, twelve holes were drilled along the ¾’’ border of the plastic pieces
in the external and internal polypropylene plastic. Using the drill pressed holes, coinciding holes
were punched through the membranes, ensuring that the holes were flush. These holes were used
to secure #10 machine screws which are purposed to hold the entire cell construct together.
Subsequently, a ¼’’ hole was drilled through the center of the outer chambers to
accommodate a quarter inch fitting to fit 8-gauge wire. The hole was tapped and a fitting was
threaded in with Teflon tape. The 8-gauge was soldered to a copper electrode on the open end of
the outer chamber and hooked to a positive/negative lead on a power supply on the other.
The final machining was the creation of two distinct holes for the pumps to provide water
flow in each chamber. For the inner product chamber, the ¼” piece was clamped upright on a
drill press bench with one of the ¼” inch thick edges facing down. A 3/32’’ hole was drilled
straight down the center of the top ¼” thick face, ¾’’ deep. Then, a hole 1/8” in diameter was
Outer&Chamber& Inner&Chamber&

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drilled in the same location approximately 3/8’’ deep. This was the hole for the inflow tube. This
process was repeated on the opposite face to create the outflow tube. For the outer chambers, the
inflow and outflow were two holes that were drilled 3/2’’ from the center electrode hole towards
opposite diagonals. The holes accommodate fittings for ¼’’ polyethylene tubing. These holes
were also tapped for the proper threading and the fittings were threaded in with Teflon tape.
The first finished assembly of the cell consisted of an outer chamber, a copper cathode
flush against the chamber, rubber gasket, anion exchange membrane, rubber gasket, the product
chamber, a rubber gasket, cation exchange membrane, a rubber gasket, a copper anode, and a
final outer chamber respectively.
Plastic!Batch!Cell!Testing!
!
Proper scientific experimentation was used to determine the functionality and performance of the
electrodialysis cell. Salt solution at 35 parts per thousand was used as the testing solution in
order to simulate the salinity of ocean water. Thus, the resulting final salinity upon completion of
desalination is a reliable indicator of the cell’s performance with ocean water. An uninterrupted
Cell&Assembly&Creating&the&holes&with&Drill&Press

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! 12!
power source (UPS) was connected to the electrodes of the electrodialysis cell in order to
provide current. The resulting voltage, which changed in response to the varying internal
resistance of the cell, was monitored using a multimeter. As the current was supplied to the cell,
both salinity and voltage readings were logged as a function of time on a Vernier Logger Pro.
Readings were taken every two seconds until the salinity of the product water reached 0.0 parts
per thousand.
Experimental Setup

13. !
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1st
Trial: The power supply was set to 2 Ampere-hours (Ah). Each external chamber was filled
with 600 mL of 35 ppt salt water. The experiment was allowed to run for 10 hours.
Note: A 30-point moving average is used to smooth out the data in each trial.
Results: The salt water reached 0.0 ppt salinity after 6.5 hrs. Voltage data was not collected
properly because the logger pro’s voltage clips are maxed at 10 V. To get around this max
voltage reading, a series of resistors was attached to the clips, scaling the logger pro’s voltage
,5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
0.0000 2.0000 4.0000 6.0000 8.0000 10.0000 12.0000
Salinity!(ppt)
Time!(hrs)
Electrodialysis!Cell!Trial!1
Salinity!(ppt)
,5
0
5
10
15
20
25
30
35
0.0000 2.0000 4.0000 6.0000 8.0000 10.0000 12.0000
Salinity!(ppt)
Time!(hrs)
Trial!1!
30,Point!Moving!Average!
Salinity!(ppt)

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! 14!
readings down by a scale of 0.325. The corrosion of the copper electrodes also became a
problem. Because copper is fairly reactive, the copper electrodes were corroded by the HCl
produced as a byproduct of the electrodialysis reaction. Therefore, they would be unable to go
through the desalination process a second time.
As a result, these copper electrodes were replaced by 304 stainless steel electrodes.
Coated with chromium, this metal is much less reactive making it less susceptible to corrosion.
2nd
Trial: The power supplied was increased from an initial 2 Ah to 5 Ah by the end of the trial.
600 mL’s of 35 ppt salt water was placed in each external compartment to begin the trial. The
experiment was allowed to run for 3.75 hours.
Copper&Electrodes& Copper&Electrodes&Corroded&
304&Stainless&Steel&Electrodes
,5
0
5
10
15
20
25
30
35
40
0 0.5 1 1.5 2 2.5 3 3.5 4
Time!(hrs)
Electrodialysis!Cell!Trial!2
Salinity!(ppt)
Voltage!(V)

15. !
! 15!
Note: The voltage data has been multiplied by a factor of 2.333 to account for the series of
resistors.
Results: The salt water reached a purified 0.0 ppt after 3.75 hrs. However, because the power
supplied was increased as the trial continued, the data provided could not yield an accurate
voltage data. More trials were required in order to determine voltage curve at a constant Ah.
3rd
– 5th
Trials: These experiments were run at 5Ah with 500 mL, 35 ppt salt water in each of the
chambers. The primary goal of these trials was to determine a voltage curve. This voltage curve
was used in the programming of the Arduino in the final model. Trial 4 had 600mL.
0
5
10
15
20
25
30
35
40
0 0.5 1 1.5 2 2.5 3 3.5 4
Time!(hrs)
Trial!2
30,Point!Moving!Average
Salinity!(ppt)
Voltage!(V)
0
10
20
30
40
50
60
70
0 0.5 1 1.5 2 2.5 3
Time!(hrs)
Electrodialysis!Trial!3:!5!Ah!
Salinity!(ppt)
Voltage!(V)

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3rd
Trial Results: The salt water reached a salinity of 0.0 ppt after 2.5 hrs. 450 mL of this water
were recovered for a 90% product efficiency. The graph experiences a few spikes due a probe
being out of place – handling the probes caused a fluctuation in readings.
0
10
20
30
40
50
60
0 0.5 1 1.5 2 2.5 3
Time!(hrs)
Trial!3
30,Point!Moving!Average
Salinity!(ppt)
Voltage!(V)
,5
0
5
10
15
20
25
30
35
0 0.5 1 1.5 2 2.5
Time!(hrs)
Electrodialysis!Trial!4:!5!Ah
Salinity!(ppt)
Voltage!(V)

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! 17!
4th
Trial Results: This trial was allowed to run for 12 hours. The graph reflects a focused portion
of the data. The salt water reached a salinity of 0.0 ppt after 2.5 hours. Approximately 550 mL
were recovered, yielding a 92% product efficiency.
,5
0
5
10
15
20
25
30
35
0 0.5 1 1.5 2 2.5
Time!(hrs)
Trial!4!
30,Point!Moving!Average
Salinity!(ppt)
Voltage!(V)
,5
0
5
10
15
20
25
30
35
40
0 0.5 1 1.5 2 2.5 3
Time!(hrs)
Electrodialysis!Trial!5:!5!Ah
Salinity!(ppt)
Voltage!(V)

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! 18!
5th
Trial Results: The salt water reached a salinity of 0.0 ppt after slightly over 2.5 hours.
Approximately 500 mL of this purified water were recovered, achieving a 100% product
efficiency.
,5
0
5
10
15
20
25
30
35
0 0.5 1 1.5 2 2.5 3
Time!(hrs)
Trial!5
30,Point!Moving!Average
Salinity!(ppt)
Voltage
2.457777778,!
30.67814754
0
5
10
15
20
25
30
35
0 0.5 1 1.5 2 2.5 3
Time!(hrs)
Average!Voltage!Curve!5!Ah
Trials!3,5
Voltage!(V)

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! 19!
Clear&Purified&Water&from&Trials&1,&5,&3&respectively& & Purified&Water&from&all&trials&2,&1,&5,&3,&4&respectively&&
Data!Analysis!
!
As observed in the above images, the purified water from trial 2 is slightly yellow. In this
trial 2, the cell continued to run after the salinity reached 0.0 ppt. The yellow discoloration could
be a result of the cell continuing to function – when Na+
ions are scarce, electrodialysis shows a
preference for transporting Fe3+
ions. In this case, after complete desalination of the salt water,
electrodialysis begins to transport the Fe within the stainless steel electrodes, transporting it
across both membranes, discoloring the purified water. As iron mixed in water is harmless to the
human body, water with the Fe3+
is still consumable. However, to combat this problem, the team
decided to control the power supply with an Arduino, preventing water discoloration as a result
of electrodialysis.
The experimental data revealed that the electrodialysis system consistently and
without fail removed all of the salt from the salt water as the solution within the product
chamber reached a salinity of 0.0 ppt. However, additional data analysis was required to
program the Arduino, which needed to shut the power supply to the cell as the salt water reached

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a salinity of 0.0 ppt. At 5 Ah, the cell fully desalinated the salt water after 2.476 hours. The 5Ah
voltage curve also reached an upper limit of 30.678 volts. This data was used to program the
Arduino to control the supply of power to the cell in the final model.
Early!Prototype!of!Integrated!Power!Delivery!Electrodialysis!Desalination!
System!(IPDEDS)!
!
The final model was designed to incorporate the original electrodialysis cell design, solar
panels, and a plastic case for portability, producing a fully power independent desalination
system.
The team built an early prototype of this final design. Three circular containers formed
the external chambers for the salt water. Each container is placed tangent to the others, forming a
shape loosely resembling a triangle. On top of each of these three containers is piping that
connects to a cross fitting. An inlet tube extends from the cross fitting to a funnel.
In the final model, the electrodialysis cell lies horizontally, with the electrode wire
pointing upwards, below these three containers, separated by a series of rubber stoppers. This
electrode wire is in empty space formed by the three circular containers. Rubber stoppers are
located on the side of the cell facing the ground, propping it up so that the electrode wire does
not touch the ground.
Insulated wiring connects the electrodes to a voltage regulator. This voltage regulator is
then connected by more wiring to a battery. The battery has a capacity of 15000 mAh (=15 Ah),
with a max voltage of 12V. The voltage regulator allows the 12 V battery to power a cell that hits
upwards of 30V. As the cell desalinates the salt water, the voltage returned to the battery from
the cell increases. However, the voltage regulator ensures the battery receives a constant voltage,
ensuring the flow of power.

21. !
! 21!
The battery is then connected to an Arduino (a programmable micro-controller) for
control. The Arduino is connected to a voltage sensor that is connected to the two electrodes. The
Arduino receives voltage readings in order to determine when to turn the battery off. The off/on
process is determined by the average voltage curve derived from trials 3-5.
For water flow, angle fittings are used with the 1/4” piping. Small holes are drilled into
the small containers for ease of access. The pumps (connected to the tubing) are placed within
each circular container. Wires also connect the pumps to the main battery.
When the Arduino has detected completion of the desalination process, it cuts power to
the cell while retaining power to the pumps and switching power a series of UV lights located in
the circular product container, which serve to sanitize. The Arduino controls the UV lights and
pumps for a two-minute cycle, allowing the product compartment to fully cycle all of the potable
water, ensuring disablement and death of all biological organisms and pathogens (product
compartment flow rate = 1.5 min p500mL).
These components are placed within a plastic casing of 10” x 10” x 10”. To create a
robust functionality allowing for easy user convenience of refilling the system with salt water, a
funnel is fixed into an external hole in the plastic casing. An LED indicator is also present on the
top of the plastic casing. When the Arduino continues to supply power to the battery, the LED
remains on. Once the Arduino cuts off the supply of energy, the LED turns off, signaling to the
user that the water is completely purified.
On the surface of the plastic casing, a solar panel is fixed onto one of the external sides.
Wiring connects these solar panels to the series of batteries on the inside.
As the desalination process achieves completion, an external switch allows the two
byproduct streams meet up in a separate internal chamber. This allows the two byproducts to

22. !
! 22!
neutralize each other. This also leads to an external spigot that allows safe disposal of dangerous
byproducts.
Finally, within the product compartment (both cell product chamber and the external
circular product container) a piece of tubing is positioned functioning to connect to an external
spigot for convenient output of water. ! !
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Market!Plan!
Freshwater availability is the greatest global risk based on impact to society, as a measure
of devastation (World Economic Forum, 2015). Only 2.5% of the earth’s water resources are
freshwater. 70% of that 2.5% is frozen in the ice caps of Antarctica and Greenland; only 0.7% of
the world’s total water resources is available for use. Currently, this means that 900 million
people rely on unimproved drinking water. By 2025, domestic freshwater use is expected to rise
by 150%. Within the next 50 years, as developing countries increase their water needs, experts
predict that a volume of freshwater analogous to 3-5 planets will be needed.
However, even these statistics do not account for another potentially troubling factor:
climate change. Climate change intensifies the water cycle, causing the processes of evaporation
and transpiration to become faster decreasing the world’s freshwater availability. Global
warming also intensifies the process of precipitation, causing the atmosphere to hold a greater
amount of water, which in turn leads to heavier rainfall when the air cools. Although increased
Expected&Water&Availability&in&2025&

24. !
! 24!
rainfall may lead to temporarily increased freshwater resources in some areas, heavier rainfall
also means that water moves more rapidly from the atmosphere to the oceans, reducing our
ability to store and use it, thus decreasing freshwater availability. An increase of 2˚C would also
cause a 5-15% depletion of groundwater resources. Additionally, global warming would
cause the glaciers to melt, converting over 70% of the world’s freshwater resources to salt
water.
While the situation may be dire, there is great opportunity in utilizing a major untapped
reservoir: the ocean. Although desalination techniques exist, there are a very limited number in a
portable form; most processes are only capable of function on an industrial level. A portable
purification and desalination device would revolutionize the water supply industry. However,
converting salt water to clean drinking water on a portable scale presents a dilemma: the leading
desalination processes, reverse osmosis and nanofiltration, require huge pressures ranging from
50 to 1,000 psig, and is therefore energy and capital intensive. In contrast, electrodialysis is a low
pressure desalination process requiring lower power (electricity), making it the most suitable
choice for a portable device.
The IPDEDS meets the unmet needs of segments of population having access to sea
or brackish water, limited power supply and low investment time and capital. Populations
such as people in poor coastal regions, defense personnel in tactical and advance units, and
populations affected by natural disasters are primary targets for this device.
Out of the 900 million people living in water stressed areas, 37% live in Africa, with a
majority living along the northern and southern coasts. With the potential to desalinate 4.8 L per
day, many of these coastal countries will experience massively decreased water stress. In
addition, with 80% of illnesses in developing countries related to poor water conditions, the

25. !
! 25!
device can also lead to an increase in life expectancy by contributing to decrease in disease and
deaths.
Increased freshwater availability also tackles another hard fought problem: economic
development. Every dollar spent on water and desalination generates another $8 as a result of
saved time, increased productivity, and reduced health care costs. By increasing freshwater
resources, African countries can potentially achieve 5-25% gains in GDP.
The portable salt water desalination system can also be used for military applications. For
example, it could be used by troops in long distance combat missions, as an emergency kit for
naval departures, or as a resource for long-term stays in coastal regions. The device provides a
reliable source of clean water, regardless of initial water condition. With increased US defense
presence in the Middle East and other water stressed areas, this device could be of great utility to
the tactical and advanced forces in the field. Historically, military personnel have suffered from a
lack of clean water. For example, 2/3 of the soldiers who fought in the American Civil War died
from poor water and sanitation conditions. With this device in place, units will be kept fit and
healthy, avoiding possible illness or death from water-related causes.
Troops are currently supplied with the life straw, a device that separates water from
impurities through pressure created by the vacuum of your mouth. However, this device does not
filter out salt; it only separates micro-organic particles. Although this device is lightweight, the
life straw cannot create drinkable water for troops stationed near saltwater, effectively curtailing
its practical usage. In contrast, the electrodialysis device is practical for brine and brackish water.
Another possible use for the desalination system is in survival applications such as
hurricanes, earthquakes, and shipwrecks. As an interesting observation, two large ships are lost
at sea every week worldwide. When resources are low, the portable desalination system could

26. !
! 26!
supply the crew of these ships with water from the ocean around them, preventing dehydration.
In the worst case scenario of a shipwreck, survivors are often isolated with few supplies. In a life
raft supplied with the device, shipwreck survivors would have a supply of life-supporting water,
living up to 8 to 10 days longer, providing a greater period of time for rescuers to find them.
Most life rafts are equipped with solar stills. Solar stills desalinate water by using the heat
of the sun to evaporate water, cooling the device, and then collecting the water. However, they
are unpredictable and inefficient due to their reliance on external factors. Solar stills rely on
favorable weather conditions to operate at the maximum efficiency of 0.8 liters per kWh – it
needs a clear and sunny day, in addition to considerably warm temperatures, to operate
efficiently. If the weather conditions are not favorable, the solar still could be easily destroyed or
simply not effective. In the U.S. alone there are up to 60-70 major and minor storms on a yearly
basis. Thus, relying on a solar still during a shipwreck a gamble. In contrast, the electrodialysis
device relies solely on electricity, making it more reliable during storms and other weather
conditions. In addition, the device is more efficient, producing 2 liters per day on 2 Ah, scaling
up to 4.8 liters per day on 5 Ah.
Overall, the portability of a salt desalination system can make a huge impact on the
market. With 900 million people lacking adequate water supplies, there is a market for 225
million devices, assuming a family of 4. With an active frontline personnel population of 1.4
million and an average platoon size of 25 men, there is another market for 56,000 devices in the
military alone. As a survival device, there is a market of over 12.077 million devices as there are
430 naval ships in active service and the reserve fleet, 86,733 commercial ships, and 11.99
million recreational boats

27. !
! 27!
Military, survival, and even third world needs are just a few of the significant
applications the portable salt water purifier can satisfy. As a device more efficient and effective
than alternate forms of water desalination and purification, there is a promising market potential
for this innovative product. In summary, there is a very sizable market opportunity for IPDEDS.

28. !
! 28!
Research!and!Explanation!of!Existing!
Technology!
In recent decades, one of the most prevalent issues worldwide has been the need for an
easily-accessible, potable water supply. It has been projected that there will be a 53% increase in
the global needs of water, from 4500 billion m3
to 6900 billion m3
, by the year 2030.
Consequently, as scientists have turned to a previously ignored source of water, the oceans, to
prevent further shortages. In the past 50 years, scientists have developed two distinct methods of
desalinating ocean water, thermal distillation and membrane technologies. While these
technologies have demonstrated potential in the industrial setting, each newly developed
technique possesses the same major flaws when applied to fundamental use: high energy usage
and extremely high capital and/or operating costs.
The Dow High team worked to combat these issues by constructing an energy-
independent, cost-effective electrodialysis cell that utilizes membrane technologies on a small
scale to produce 500-600 milliliters of drinking water in a 2.5 hour time period. Current
electrodialysis technologies are primarily used in the industrial setting to desalinate brackish
water, rather than seawater, because of the large energy usage of the ion-exchange membranes
necessary at high salinity levels. The Dow High electrodialysis cell utilized hybrid dimethyl
membranes which dramatically reduce the energy consumption of the cell, while still recovering
large volumes of water. While existing electrodialysis technologies are not primarily used for
desalination, a major problem in these technologies is the need for the resulting water to be
treated for pathogens before it is safe to drink. Another major problem in current electrodialysis
technologies is the need for the resulting water to be treated for pathogens before it is safe to
drink. The Dow High team addressed this problem by implementing 250-260 nanometers

29. !
! 29!
wavelength UV lights into the design. This UV light disinfects the water by breaking molecular
bonds within bacterial and viral DNA, thereby killing and disabling the microorganisms. The
team also worked to create a technology that was entirely energy-independent and portable by
utilizing photovoltaic cells to supply both the current for ion exchange and minimal power
required for the pumps. This innovation allows for the cell to function in a broad range of
applications, such as emergency survival and military equipment, unlike the static industrial
water conversion plants. Dow High’s electrodialysis cell exhibits promising future potential as
well. The team has the ability to further optimize the efficacy of the electrodialysis cell by
reducing the distance between the cation and anion membranes, in order to decrease the
electrical resistance. Increasing the flux of the membranes so larger volumes of ions are able to
pass through would also improve the performance of the cell, allowing more potable water to be
recovered in an even shorter time frame.
In comparison to thermal technologies, the earliest attempts at the desalination of water,
electrodialysis demonstrates far greater efficiency at both lower energy and financial costs.
Thermal desalination operates by heating saline water to a boil and collecting the condensed
vapor in order to produce potable water. This process, called distillation, has been divided into
three groups of technologies based on the heat source and pressure under which the system
functions. These groups include Multi-Stage Flash Distillation (MSF), Multi-Effect Distillation
(MED), and Vapor Compression Distillation. MSF Distillation alone produces 42% of the
worldwide desalination capacity. However, this process works at an incredibly low efficiency
and involves exceptionally high costs. Only a small percentage of feed water—water that is led
into the cell to be desalinated—is actually converted into water vapor and condensed, leading
this process to be inefficient and time consuming. In comparison, the electrodialysis cell operates

30. !
! 30!
at nearly 100% efficiency, dramatically reducing costs and the duration of the desalination
process. The design of the MSF unit itself has a high opportunity cost as well, in that the MSF
plants are subject to corrosion, erosion, and impingement attacks unless stainless steel is used for
every piece of equipment, which leads to skyrocketing expenses. Another disadvantage of this
distillation process is the energy need to desalinate 500 milliliters of seawater. Due to the high
enthalpy of vaporization of water, MSF distillation requires 1131 kilojoules to boil 500 milliliters
of water, whereas electrodialysis requires only 57.8 kilojoules. This is expressed as an almost 20
fold decrease in energy usage for the Dow High electrodialysis cell. The less widely used MED
process also requires large amounts of energy for very little water production due to the low
pressures of the system. Finally, Vapor Compression Distillation is externally dependent and
requires a mechanical compressor to generate heat for the evaporation process. The technology is
also small in capacity, resulting in reduced water output for similar energy costs .
Another membrane technology comparable to electrodialysis, reverse osmosis, utilizes
pressure to force seawater through a semi-permeable membrane, leaving the salt behind. One
disadvantage of this mechanism is the need for pretreatments of the water such as coagulation,
sand filtration, or ultrafiltration. This pre-conditioning of water is needed to protect the
membranes, and the extent of these pre-treatment requirements depends on a variety of factors,
such as seawater composition and temperature, seawater intake, membrane materials, and
recovery ratio. This leads to high upfront costs that are not necessary for the electrodialysis cell
since water does not pass through the membranes during the electrodialysis desalination process.
Reverse osmosis also requires high pressure pumps that range from 800-1,000 psi, compared to
the pumps needed for electrodialysis which are both cheaper and more efficient because they
operate at a much lower pressure of 70 psi, with a comparable flow rate of 100 milliliters in 20

31. !
! 31!
seconds. Furthermore, reverse osmosis is only approximately 50% efficient for seawater because
a large portion of feed water must be discharged as concentrate, in order to prevent the super-
saturation of salts within the unit. Ultimately, electrodialysis proves to have a higher efficacy
than reverse osmosis because it is selectively permeable to ions, thereby not allowing the
movement of large water molecules through the membranes, resulting in a faster rate of
desalination.
!
! !

32. !
! 32!
Financial!Plan!
Electrodialysis Cell Budget! ! !
!
!
!!
BUDGETED AMOUNT
$1,000.00
$1,000.00! !
TOTAL COSTS $907.91! !
$907.91
91%! !
DIFFERENCE 9%! !
$92.09
Expenditure Location Notes Cost
Carbon Paper Staples Filter for initial water ! $19.99
300V Rubber Cord 1/4" x4 Home Depot $1.72
Clear Acrylic Sheet (.22x24x28) Home Depot $59.97
Noninsulated Alligator Clips Home Depot! Testing ! $4.38
10' Vinyl Tube 1/4" Home Depot $5.16
LOCTITE M&C Epoxy Home Depot! ! $4.99 !
LOCTITE Plastic Epoxy Home Depot! ! $5.47 !
Silicone Sealant Home Depot! Used for initial Wood Cell ! $5.68 !
Terminal and Crimping Tool Kit Home Depot! ! $5.95 !
Clear Acrylic Sheet (0.93x11x14) Home Depot! Used for initial Wood Cell ! $33.46 !
25' Polyethylene Tubing 1/4" McMaster! Not used in final experimental cell ! $18.50 !
24"x24" Polypropylene Sheet 1/4" McMaster ! Polyethylene is resistant to both base ! $33.32 !
12"x24" Polypropylene Sheet 1" McMaster! and acid ! $63.89 !
2' 36" Width Neoprene Rubber 1/8" McMaster! ! $72.20 !
AMI-7001S Anion Membrane Sheet 48"x20" Membranes Int. ! ! $125.00 !
CMI-7000S Cation Membrane Sheet 48" x 20" Membranes Int. ! ! $125.00 !
12" Stainless Steel Tubing 1/8" McMaster! Not used in final experimental cell ! $8.04 !
UV lights (380 nm) x10 SuperBright LEDs! ! $6.70 !
Male Connector 1/8" tube x 1/8" MNPT x2 Midland Valve! ! $15.00 !
Ferrule Set 1/4" Tube x4 Midland Valve! ! $3.72 !
Polyethylene 1/4" x15' Lowe's! ! $2.85 !
6' Solid Bare Copper Tubing 1/8" Lowe's! ! $1.78 !
No 10 Screws x 12 Lowe's! ! $1.96 !
No 10 Flat Washers 24 CT Lowe's! ! $0.98 !
1/4" P2C x 1/8" MIP x4 Lowe's! ! $12.76 !
$0.00
$200.00
$400.00
$600.00
$800.00
$1,000.00
$1,200.00
EXPENSES
Initial Costs Avaliable
Budget
Expenditures Avaliable

33. !
! 33!
Arduino Uno GearBest! ! $5.52 !
Portable DC 12V 15000mAh Li-ion Battery x2 Ebay! ! $66.38 !
DC-DC Adjustable Voltage Regulator Module Vetco Electronics! ! $6.95 !
Global Pipe Fitting 90 Degree Tee Global Industrial! ! $4.70 !
1/4" OD Tube x 1/4" OD Tube LIQUIfit Union Elbow x10 US Plastic Corp. ! ! $19.20 !
PowerFilm OEM Flexible Solar Paneling x4 SolarMade! ! $112.68 !
X2Power Rechargeable NiMH D Battery 2 Pack Batteries and Bulbs! ! $30.99 !
Benziomatic Silver Solder Kit w/Flux Home Depot! ! $5.97 !
Lead Free Silver Solder Home Depot! ! $4.61 !
Hose Clamp 7/32" to 5/8" SS x8 Home Depot! ! $11.92 !
304 Stainless Steel Sheets 5"x5" x2 Midland Steel! ! $0.52 !
Cost Analysis for Experimental Electrodialysis Cell
Note: Costs in Bulk estimated from producers price! !
Item Comments! Cost ! Cost in Bulk!
7"x7" Anion Membrane $6.38 ! $2.72 !
7"x7" Cation Membrane $6.38 ! $2.72 !
7"x7" w/ 5.5"x5.5" cutout rubber gaskets x4 $2.09 ! $0.78 !
1/4" 7"x7" w/ 5.5"x5.5" cutout Polyproplene Sheet Inner Compartment! $1.08 ! $0.27 !
1" 7"x7" w/ 5.5"x5.5"x.0.75" milled out Polyproplene Sheet x2 Outer Compartment! $10.87 ! $1.08 !
304 Stainless Steel 5"x5" Sheet x2 Estimated Price! $0.52 ! $0.52 !
6" Solid Bare Copper Tubing 1/8" $0.15 ! $0.15 !
1/4 of Ferrule Set 1/4 Tube $0.23 ! $0.11 !
No 10 Screws x 12 $1.96 ! $0.55 !
No 10 Flat Washers x12 $0.49 ! $0.15 !
Male Connector 1/8" tube x 1/8" MNPT x2! ! $15.00 ! $3.56 !
1/4" P2C x 1/8" MIP x4! ! $12.76 ! $4.09 !
Polyethylene Tubing 1/4" 2' $0.38 ! $0.38 !
Total: $58.29 ! $17.08 !
Cost Analysis for Inclusive Final Model
Note: Costs in Bulk estimated from producer’s price! !
Item! Notes! Cost! Cost in Bulk!
Electrodialysis Cell (from above) After Process Economics! $58.29 ! $17.08 !
Plastic Shell (3D Printed) 1'x1'x1' Estimated Price! $0.16 ! $0.16 !
X2 Power Rechargeable NiMH D Battery (1) $15.49 ! $15.49 !
PowerFilm OEM Flexible Solar Paneling x1! $28.17 ! $11.68 !
1/4" OD Tube x 1/4" OD Tube LIQUIfit Union Elbow x8! $15.36 ! $10.24 !
DC-DC Adjustable Voltage Regulator Module ! $6.95 ! $0.57 !
Global Pipe Fitting 90 Degree Tee (cross fitting)! $4.70 ! $2.74 !
Arduino Uno! ! $5.52 ! $5.52 !
UV lights (380 nm) x3! ! $2.01 ! $2.01 !
LED (1) Estimated Price! $0.15 ! $0.15 !
Wiring Estimated Price! $0.20 ! $0.20 !
Total: $137.00 ! $65.84 !
!
!

34. !
! 34!
Funding!
!
! The team used the $1,000 grant to purchase the materials necessary to produce, test,
and improve on two iterations of their electrodialysis cell, as well as produce an early prototype
of the IPDEDS, a potential product Due to many of the materials being industrial-grade and not
commonly available to individual consumers, 91% of the grant was used.
The first iteration of the cell expended 14.66% of the grant. The largest cost was clear
acrylic sheets, items that would not be used in further development. Plywood, a potentially large
cost, was sourced for free from the school’s woodshop. A few of the items bought in this stage
were tools for future testing – the alligator clips, sealant, and epoxies were used for the plastic
cell and the final model. On the other hand, many of the items bought were not used in either
further testing or construction. For example, the rubber cord, vinyl tubing, and acrylic sheets
were deserted.
Although the total initial cost of the cell was only $58.29, 49.1% of the grant was used in
the second iteration of the cell. Many products were industrial materials not readily available to
the average consumer, causing inflated costs. Specifically, many of the fittings and plastics are
far cheaper in huge quantities. Some of these industrial materials also came in sizes or quantities
not ideal for development, and extra funds were spent on acquiring excessive material. For
example, the ionic exchange membranes were 19.5x larger than necessary. During the
development of this second iteration, some of the materials were bought and then exchanged for
other materials. The polyethylene tubing bought from McMaster was too thick to fit into fittings,
and was eventually swapped for polyethylene tubing from Lowe’s.
Costs derived from the development of the final model amounted to 26.4% of the grant.
Costs were inflated for similar reasons: fittings were far more expensive in small quantities and

35. !
! 35!
excess solar paneling was bought. Upon concluding development, the final model’s initial costs
amounted to $137.00. However, when buying in bulk, the cost of the final model decreases to
$65.84. Upon the development of streamlined processes involved in procurement and creation,
the cost of production decreases to $50.00.
In order to the secure the funding required to achieve these economies of scale, the Dow
High Team will apply to a variety of grants. The funding would allow for the further
development of the IPDEDS. The team would seek to receive a grant from the US Department of
the Interior Bureau of Reclamation’s Desalination and Water Purification Research Program.
This program allows research and studies to receive up to a maximum of $5 million per year.
The team believes that the IPDEDS has a key advantage in applying for this grant: in contrast to
other desalination techniques the IPDEDS is mobile and extremely valuable on a local scale.
The team also aims to gain funding from the California Department of Water Resources.
This department offers $8.7-$21.5 million dollars for the development of water desalination. The
team believes that the IPDEDS is positioned to win funding due to California’s current
conditions. It has been forecasted that in 12-18 months, 22 million people will be without
freshwater. The IPDEDS could provide a source of freshwater to an area severely impacted by
drought.
In addition, the team plans on seeking funding from the United States Senate Drinking
Water State Revolving Fund Loan Program. Each state has a fund of $8,787,000 to $82,674,000
to use in funding for the development of drinking water systems. The IPDEDS is a revolutionary
product in drinking water production because of its ability to portably desalinate salt water. This
ability dramatically increases the availability of salt water in coastal regions.

36. !
! 36!
The team also aims to secure their intellectual property through a variety of patents. The
IPDEDS will be secured through an integrated systems patent, providing 12-14 years to develop
better versions of the device. The design and construction methods of the cell will also be
patented, providing additional security.
!
The graph above demonstrates the process economics of the three distinct levels of
production. In the current prototype stage, material and production costs remain high. However,
as production begins to increase into the hundreds, cost of materials and production is driven
down by the quantity produced. In the final commercial stage, the costs are further lowered with
a massive increase in quantity produced. A profit margin of 20% is applied to the costs in all
levels of production. The process economics of the IPDEDS clearly demonstrates the ability to
lower the price of the device with an increase in quantity produced. The projected commercial
price is a testament to the cost- effective nature of the IPDEDS.!

37. !
! 37!
!The graph above shows the increased cost effectiveness of the electrodialysis cell with
modular scaling. The addition of one product chamber, which only adds ½” to the overall
IPDEDS size, effectively doubles the purified water output only at a linear marginal cost of
$1.56 per unit. While one product chamber yields a cost of 2.5 cents per liter of water, an
increase of 4 modules decreases the cost of each liter to an astonishing half cent.

38. !
! 38!
Project!Management!&!Timeline!
!
!
!
!
!
!
!
!
!
!
!
!
!
!

39. !
! 39!
Graphical!Representation!
!

40. !
! 40!
1
1
2
2
3
3
4
4
A A
B B
C C
D D
SHEET 1 OF 1
DRAWN
CHECKED
QA
MFG
APPROVED
sarkars 3/8/2016
DWG NO
Expanded Assembly
TITLE
SIZE
C
SCALE
REV

41. !
! 41!
! !
1
1
2
2
3
3
4
4
A A
B B
C C
D D
SHEET 1 OF 1
DRAWN
CHECKED
QA
MFG
APPROVED
sarkars 2/29/2016
DWG NO
Outer Membrane
TITLE
SIZE
C
SCALE
REV
7.00
7.00
5.50
5.50
1.00
.375
.50
3.50
3.50
.125
2.00 2.00
.375
2.00 2.00
Outer Membrane
Electrode Rod
1
1
2
2
3
3
4
4
A A
B B
C C
D D
SHEET 1 OF 1
DRAWN
CHECKED
QA
MFG
APPROVED
sarkars 2/29/2016
DWG NO
Inner Membrane
TITLE
SIZE
C
SCALE
REV
7.00
7.00
3.50
5.50
5.50
2.00
2.00 .196
.375
.375
Clearance Hole
Water Tubes
Inner Membrane
2.00 2.00
.125

42. !
! 42!
1
1
2
2
3
3
4
4
A A
B B
C C
D D
SHEET 1 OF 1
DRAWN
CHECKED
QA
MFG
APPROVED
Abhijit 3/31/2016
DWG NO
Assembled Assembly Assembly
TITLE
SIZE
C
SCALE
REV

43. !
! 43!
Appendix!A!
!
!
Cell&Assembly&
Cell&Assembly&
Electrodialysis&Cell&Experimentation&Setup& Pure&Water&Recovery&PostKExperimentation&

44. !
! 44!
!
Rubber&Gasket&
Outer&Chamber&
Cell&Vertical&View& Cell&Horizontal&View&

45. !
! 45!
!
Inner&Chamber&Side&View&
Inner&Chamber&Front&View&
Copper&Electrode&w/o&Electrode&Wire&
Outer&Chamber&with&Copper&electrode&and&Electrode&Wire&
Inner&View&

46. !
! 46!
!
Inner&Chamber&with&Copper&Piping&and&Fittings&
!
!
Outer&Chamber&with&Electrode&and&Electrode&WIre&Outer&
View&
Blowtorch&Soldering&Copper&Wire&to&Electrode&
Cell&Side&View&

47. !
! 47!
!
Cell&Side&View&
!
!
Blowtorch&Soldering&Copper&Wire&to&Stainless&Steel&Electrode&
!
Cell&Side&View&
Stainless&Steel&w/&Copper&Wire&in&Outer&
Chambers&

48. !
! 48!
!
Early&Drawing&of&the&IPDEDS&
! !

49. !
! 49!
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Krishna, H. J. (n.d.). Introduction to Desalination Technologies. Retrieved March 31, 2016, from
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! 50!
Leflaive, X. (2012, May 21). Water Outlook to 2050: The OECD calls for early and strategic
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early-and-strategic-action/
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Mcintyre, N. (2012, October 21). How will climate change impact on water security? Retrieved
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!
!