Christopher Gordon
Professor Elisa Warford
WRIT 340
May 1, 2013
Water Filtration: Relieving the Water Crisis Through Innovation
As the world’s population expands, the need for water is becoming more apparent. Statistics
show that fresh water resources are depleting, causing engineers to think of new ways to create
potable water. By finding exactly what causes water-related deaths, engineers can pinpoint what
their filtration methods need to eliminate. Countries that have lacked access to clean water are
now able to attain clean water through original filtration methods and applications. Products
such as the Lifestraw and the MadiDrop provide impoverished nations with methods to obtain
drinkable water and live a more sustained life. Clean water presents multiple benefits to people,
including the obvious health benefits as well as community improvements.
The Need for Fresh Water
There is an increasing demand for water as the world’s population continues to grow at a rapid
pace. This demand is forcing people throughout the world to start discovering and innovating
new ways to help meet people’s basic need for water. However, the current situation implies
enough is not being done to help everyone. You may argue that there is plenty of water on Earth.
You would be right, as the Earth is comprised of about 70% water. Unfortunately, less than 1%
of this water is fresh, the type humans need for survival [1]. About 780 million people lack
access to clean water, with 3.4 million people dying each year from a water-related disease [2].
Such shocking numbers call for more measures to be implemented in order to help those who
have limited water resources. The statistics for children and water-related deaths paint a more
horrific picture (Fig. 1). Although the number of deaths has decreased since 2009, this number
can still improve.
Figure 1: Recent statistics on water
related deaths for children.
Source: water.org
The scarcity of water has caused an increase in conflicts regarding water. Out of the 181 reported
conflicts over water from 3000 B.C. to the end of 2007, 59 of these conflicts have occurred in the
21st century [3]. This increase indicates that people are growing tense as they recognize the
world’s water supply is slowly declining. Officials have also recognized the current need for new
resources of water. Interior Minister of Taiwan Lee Hung-yuan voiced his concern to citizens.
He warned the Taiwanese that their current supply of water will be inadequate by 2030, leading
to problems with food and energy in the near future [4].
With such concern, many professionals are hurrying to solve this global crisis. Engineers are
creating new water filtration methods and applications that will help alleviate these issues. These
applications have been continually developing and are now reaching to the parts of the world that
need it most.
Impurities in Water
Although these statistics are concerning, many of us in the United States find them difficult to
relate to. We have many clean resources of water as compared to struggling areas in Asia and
Africa. The water we typically receive is free from most impurities that are commonly found in
water. These impurities are the direct cause of these deaths, as well as the reason why fresh water
is becoming a valuable asset around the world. Pollutants such as sediment, arsenic, nitrates,
biological pathogens (waterborne organisms), calcium, magnesium, mercury, zinc, and copper
make water contaminated and unsuitable for human needs [5]. Many of these impurities have
been linked to multiple forms of cancer, the main reason for water-related deaths. Engineers
have pinpointed these sources of water-related deaths and have created innovative purification
methods that greatly reduce the number of contaminants. By recognizing the cause of these
deaths, they are able to design filtration methods and systems that directly eliminate these
unwanted elements.
Recent Filtration Methods and Applications: How They Work
Filtration systems have been utilized for many years, but many methods have developed during
the 21st century. With technological advances, engineers continue to invent products and
methods that help the water crisis. The more recent methods include ultraviolet and desalination
membrane filtration, which improve efficiency in reducing foreign objects in water compared to
past filtration procedures. Applications such as the Lifestraw and the MadiDrop are now being
used in parts of the world that desperately need new ways to create fresh water.
Ultraviolet Filtration
Ultraviolet filtration is a method that has been used recently in addressing the water crisis.
Ultraviolet filtration deactivates almost all pathogens in the unclean water. The water is passed
under an ultraviolet (UV) light source (Fig. 2), which eliminates the pathogens. Engineers have
recently designed a UV system that kills bacteria effectively while also saving energy and
expenses. The system utilizes microwaves which energize lamps to generate a particular UV
wavelength of 245 nanometers (nm), which is optimal for removing pathogens [7]. UV light kills
bacteria in the water by damaging its DNA. The nucleic bonds are broken and then incorrectly
paired back together. This causes DNA to be misread, causing the bacteria to be unable to
function normally or reproduce. However, this method is typically used along with other filters
as it is unable to remove dirt or particles from the water.
Advances in engineering have increased the lifetime of these lamps, causing systems to operate
more consistently and providing fresh water with greater regularity. However, a drawback is its
limited availability as it requires electricity to be used. This likely prevents its usage in less
developed areas, as they typically lack access to electricity. Engineers could expand research on
ultraviolet filtration to potentially provide it to impoverished areas without electricity.
Figure 2: Close up view of multiple
ultraviolet filters.
Source: wateronline.com
Desalination Membrane Filtration
The latest advances in filtration methods have been explored by the Massachusetts Institute of
Technology (MIT). Scientists there are attempting to create a membrane which can efficiently
purify seawater, a process known as desalination. The membrane is on the nano scale, which is
10−9 meters. This is also referred to as a molecular scale. The membrane consists of graphene,
which is a sheet of bonded carbon atoms that would be arranged in a hexagonal, honeycomb
structure (Fig. 3). As water passes through this membrane, the larger salt molecules will not be
able to flow through the molecular membrane. This results in only small water molecules passing
through the pores, resulting in purified water.
Scientists at MIT are still attempting to find the correct pore size to filter seawater adequately.
With this issue, they are also hypothesizing ways to puncture the graphene to make the desired
structure [8]. Research in this area is especially intriguing as most of the water on Earth is stored
in our oceans. In comparison to other desalination methods, the graphene membrane requires
much less energy for water purification. If completed successfully, the membrane would bring
about technological advances that could potentially give fresh water access to populations living
near the ocean.
Figure 3: Water membrane filtering
seawater. Membrane is shown as
blue. Water molecules are red and
white. Sodium and chlorine are
displayed in green and purple.
Source: earthsky.org
Lifestraw
Lifestraw is a recent invention that has directly impacted the lives of those who do not have easy
access to potable water. Lifestraw is a simple, tubular device that can filter water without the use
of electrical power (Fig. 4). The Lifestraw has filters inside of it that filter the water as it passes
through the tube. This means the device can be placed directly in unclean water and will filter to
become clean water before it enters the user’s mouth [9]. The Lifestraw only requires that air be
blown through the tube periodically in order to keep the filters clean and unclogged. Such simple
technology is changing the lives of people in Africa. Millions of Lifestraws have been sent to
areas throughout Africa that need clean water. The company is helping the water crisis by going
to many of the affected areas directly. Many users saw improvements in their lifestyle simply
because they were given a portable water filter. The Lifestraw continues to provide people in
Africa water filters, and engineers of the company continue to invent new products that these
people can easily use.
Figure 4: The Lifestraw.
Source: gizmag.com
MadiDrop
The MadiDrop is a tablet created by a nonprofit organization from the University of Virginia.
This clay tablet (Fig. 5)—comparable to the size of a coaster—contains nanoparticles of silver
which filter and disinfect unclean water. Silver is able to filter water because its ions are able to
reach the core of bacteria and bond to various sections of the cell, such as the DNA, proteins, and
enzymes. The support systems of the cell become disabled, resulting in a stoppage of cellular
growth and division. This ultimately leads to the bacteria dying, leaving only water molecules
present. The MadiDrop is simply placed in the undrinkable water, and the tablet removes
pathogens [10]. Although the tablet does not remove sediment, it is simple to use and cheap to
transport. The creators of the MadiDrop have sent many of these devices to areas in South
Africa. They also intend to teach the people there how to create more of these tablets, as the
MadiDrop is effective for only a six month period. The organization also created a similar
product which is called the PureMadi. Instead of only being a small tablet, it is a normal sized
vase which can filter water much more efficiently. Technology in the MadiDrop and the
PureMadi is as simple as the Lifestraw, and also helps to solve a very complex problem.
Figure 5: Multiple MadiDrop tablets,
compared to the size of a quarter.
Source: news.virginia.edu
Benefits of Clean Water
Engineers must consider the purpose of providing clean water to those in need. With the statistics
shown earlier, engineers can recognize the impact that clean water has on a person’s life. Fresh
water prevents dehydration effectively, which is especially crucial in warmer climates. Access to
drinkable water also provides energy to a person and allows the body to absorb nutrients more
successfully. Potable water decreases the chances of getting ailments such as kidney stones.
Clean water also prevents gastrointestinal issues such as constipation or diarrhea, the major
source of water-related deaths. In addition to personal physical health, there is also a societal
impact that clean water provides. By offering potable water to children, their education is
improved because they no longer have to miss class due to water-related sickness. The
improvement in enrollment correlates with improved knowledge and an awareness of the dangers
of contaminated water. Areas also see an improvement in agriculture as the filtered water can
now be used for growing multiple crops. Another result of clean water access is that areas which
previously did not receive such water may observe a rise in income. This increase comes from
more tourists visiting along with businesses potentially expanding their networks to these areas
[6]. With clean water becoming more accessible, the surrounding property also becomes more
valuable. Engineers acknowledge clean water’s multiple benefits as their motivation to design
such water filtration systems.
Water Filters: Creating the New Liquid Gold
Water is essential to our lives. Everyone needs a source of fresh water. Without it, people across
the world will continue to suffer from water-related diseases which usually lead to death.
Engineers are hard at work designing new ways to reduce pollutants in water. Conscious of the
benefits that clean water provides, engineers continue innovating filtration methods such as
ultraviolet disinfection and new desalination techniques. They have also created applications,
including the Lifestraw and the MadiDrop, which are being used in areas affected directly by
lack of clean water. Engineers continue to strive for creating a better planet, and water
purification is one solid step in completing this task.
References
[1] U.S. Department of the Interior. (2013, Jan. 10). How much water is there on, in, and above
the Earth? [Online]. Available: http://ga.water.usgs.gov/edu/earthhowmuch.html
[2] Water.org volunteers. (2013, Feb. 5). Water Facts [Online]. Available:
http://water.org/water-crisis/water-facts/water/
[3] H. Bigas. (2012). The Global Water Crisis: Addressing an Urgent Security Issue [Online].
Available:
http://www.inweh.unu.edu/WaterSecurity/documents/WaterSecurity_FINAL_Aug2012.pdf
[4] S. Wu. (2013, Feb. 3). China Times: Take heed of looming water crisis [Online]. Available:
http://focustaiwan.tw/ShowNews/WebNews_Detail.aspx?ID=201302030012&Type=aOPN
[5] Excel Water Technologies Inc. (2012). Common Water Problems [Online]. Available:
http://www.excelwater.com/eng/b2c/about_4.php
[6] G. Hutton. (2012). World Health Organization: Global costs and benefits of drinking-water
supply and sanitation interventions to reach the MDG target and universal coverage [Online].
Available: http://www.who.int/water_sanitation_health/publications/2012/globalcosts.pdf
[7] Severn Trent Services. (2013, Jan. 28). UV Disinfection System Kills Bacteria in Municipal
Wastewater [Online]. Available: http://news.thomasnet.com/fullstory/UV-Disinfection-Systemkills-bacteria-in-municipal-wastewater-20002035
[8] D. Conners. (2013, Jan. 21). New Water Desalination Technology Shows Promise [Online].
Available: http://earthsky.org/human-world/new-water-desalination-technology-shows-promise
[9] Lifestraw representatives (2012). Lifestraw-Features [Online]. Available:
http://www.vestergaard-frandsen.com/lifestraw/lifestraw/features
[10] University of Virginia (2013, Feb. 9). An Innovative Nanotech Water Purification Tablet for
Developing World (w/ video) [Online]. Available:
http://www.nanowerk.com/news2/newsid=28935.php