feasibility study of a solar energy as a purifier for contaminated and salt water

Napnapan National High SchoolTigbauan, Iloilo

Feasibility study of a Solar Energy as a purifier of Contaminated

and Salt water

An Undergraduate Research Paper Presented to

Mrs. Josephine Impe

Napnapan National High School

Tigbauan, Iloilo

Stephen T. To-ong

Feasibility study of a Solar Energy as purifier for Contaminated and Salt Water 1


Acknowledgment

The researcher would like to extend his sincere thanks and

appreciation to the following people who have contributed, in one

way or another, to the realization of this study. Mrs.

Josephine Impe, research adviser, for the encouragement and

support from the conceptualization to the completion of the

study. Mr.Paul T. Tejero, for

the assistance and valuable suggestions and for the invaluable

tips to improve the quality of the research study;

To-ong and Tejero families,

the wind beneath my wings as I reach my goals in life, for the

unconditional love and prayers, for understanding, and moral

support, despite of the challenges that come along;

Most of all, to Almighty

God, for giving the researcher the courage, knowledge, guidance,

love and blessings.

Stephen T. To-ong



Stephen T. To-ong. Feasibility study of a Solar Energy as a Purifier for a contaminated and salt water. Unpublished Research Paper. Napnapan National High School, Tigbauan, Iloilo.

Abstract

Distillation is one of many process available for water

purification, and sunlight is one of several forms of heat energy

that can be used to power that process. Sunlight has the

advantage of zero fuel cost but it requires more space and

generally more costly equipment.

To dispel a common belief, it is not necessary to boil water

to distill it. Simply elevating its temperature, short ofboiling,

will adequately increase the evaporation rate. In fact, although

vigorous boiling hastens the distillation process it also can

force unwanted residue into the distillate, defeating

purification. Furthermore, to boil water with sunlight requires

more costly apparatus than is needed to distill it a little more

slowly without boiling. Many levels of

purification can be achieved with this process, depending upon

the intended application. Sterilized water for medical uses

requires different process that that used to make drinking water.

For people concerned



about the quality of their municipally-supplied drinking water

and unhappy with other methods of additional purification

available to them, solar distillation of tap water or brackish

groundwater can be a pleasant, energy-efficient option.

CHAPTER 1



INTRODUCTION

Background of the Study

Only a very small percentage of the earth’s water is

available for human use, since most is salty ocean water that

cannot be used for drinking, washing, irrigation, or industry.

Usable water can be created from salt water in a process called

desalination, but the process is controversial which is expensive

and requires a lot of energy. Solar

evaporation purification (or solar desalination) is a process

that is often used to make contaminated or saltwater drinkable.

It uses only the sun's energy to generate clean, potable water.

Solar desalination plants have been installed in areas that are

commonly plagued with potable water shortages, but you can use

this technology to make a small solar desalination unit in your

own back yard. Unlike other filtration methods, solar

desalination does not require expensive equipment or replacement

parts, making it an easy and environmentally friendly choice for

water purification. Solar water

purification involves purifying water for drinking and household

purposes through the usage of solar energy in many different

ways. Using solar energy for water treatment has become more



common as it is a usually low-technology solution that works to

capture the heat and energy from the sun to make water cleaner

and healthier for human use and consumption. Solar water

treatment is particularly beneficial for rural communities, as

they do not have other forms of water purification infrastructure

and more importantly, electricity to run such structures. The

most positive feature about solar water purification is that

there is no requirement of fuel. It's precisely due to the lack

of fuel that makes solar applications relatively superior than

conventional sources of energy as it does not cause pollution

(global warming, acid rain, ozone depletion) or health hazards

associated with pollution.

Statement of the problem

Specifically, it would answer the following questions:

a) Is the solar energy an effective substitute to purify

contaminated water?



b) Can we develop a cost effective heating and surface water

reclamation system necessary to support a greenhouse production

while maintaining a zero carbon footprint?

Hypothesis

a) Solar energy is a best substitute to purify contaminated

or salt water.

b) Contaminated water or salt water which was later purified

through the solar energy is safe to drink. c) I

believe that if I design and build and solar powered water

purification system, using an evaporator stage and a condenser

stage, then the total water productivity of the system will be

increased, as compared to a typical passive solar still design.

Significance of the study

The importance of this study is to help youth:

a) understand how the process of evaporation can be used to

purify salt water for drinking; and

b) to make them practice contributing to the progress of a

group engaged in a cooperative project.



Scope and limitation

This study limits on the study of the feasibility of the

solar energy as a purifier of a contaminated or salt water. Solar

water purification is a much safer method of water treatment,

which has no possibility of chemicals decomposing themselves

during the treatment of water, thereby producing products harmful

to health. However it should be noted, that this method and its

products is relatively less known to the general population.

The materials were

limited to the 5-gallon transparent plastic bucket, 1-gallon

glass jar, Transparent plastic sheeting, Masking tape, waterproof

glue, Saltwater or contaminated water.

The study was conducted at Napnapan National

High School, Napnapan Sur, Tigbauan, Iloilo on January 18-23,

2013.

Definition of terms

For reasons of clarity and better understanding of the

study, certain important terms were defined operationally and

conceptually:



Contaminated water- undesirable state of the natural

environment being contaminated with harmful substances as a

consequence of human activities.

Feasibility study- is an evaluation and analysis of the

potential of the proposed project which is based on extensive

investigation and research to give full comfort to the decisions

makers.

Purifier- to clear from material defilement or imperfection

Salt water- Consisting of or living in salty water,

especially seawater. Solar

Energy- Solar energy refers primarily to the use of solar

radiation for practical ends. However, all renewable energies,

other than geothermal and tidal, derive their energy from the

sun.


http://en.wikipedia.org/wiki/Tidal_power

http://en.wikipedia.org/wiki/Geothermal_power

http://en.wikipedia.org/wiki/Solar_radiation

http://en.wikipedia.org/wiki/Solar_radiation


CHAPTER II

REVIEW OF RELATED LITERATURE

More than a billion people in the world today lack access to

clean drinking water and there are more people in the world’s

hospitals today suffering from water-borne diseases than any

other ailment.

As glaciers shrink, droughts increase and salt-water

intrusion spreads, the world’s current fresh water shortage is

set to worsen. But treating water is a power-intensive and hence

expensive business. It’s also one that can only become more

costly as the price of fossil-fueled electricity in social,

political, environmental and economic terms becomes apparent. The

world needs to find ways of cleaning, desalinating and

distributing water to its citizens. And it is an area for which

the use of renewable energy seems particularly apt.

However, to talk of renewable generation as a single entity

is misleading. Wind and solar power — the most likely candidates

for water treatment in non-coastal areas — are very different

beasts. Even within the category of solar power there are myriad

technologies. And each one has distinct properties that affect

where and how it can best be deployed.



Naturally, the prevailing weather conditions will be the

major factor. There is no point in erecting wind turbines in an

area where the wind is but an occasional occurrence. The reality

is that the areas where availability of clean water is currently

the most pressing issue, and the countries where it is most

likely to become one, are best suited to solar power.

In particular, concentrated photovoltaics (CPV) may prove to

be the likeliest candidate for water treatment. Like other solar

technologies, CPV converts the power of the sunlight into usable

energy. But the advanced design of its solar cells delivers far

higher energy yields than standard photovoltaics. CPV units also

have an optics system, which magnifies the power of the sun even

further, and a sun-tracker unit so that the cells follow the path

of the sun and are able to “harvest” a larger fraction of the

sun’s rays. The result is a

system that is incredibly efficient and capable of delivering far

greater levels of power from a single unit than other forms of

solar electricity generation. The net result is a system that has

the potential to be much more cost-effective.

The high efficiency

of CPV also makes it suitable for micro-generation. In the

developed world, micro-generation is often seen as a well-



intentioned whimsy on the part of wealthy but committed

environmentalists. But in the developing world, where significant

proportions of the population live in off-grid rural areas or in

overcrowded, unplanned urban sprawl, micro-generation has

immediate and obvious benefits. Like micro-finance before it,

thinking small can help solve big problems. But perhaps the

biggest advantage of linking technologies like CPV to very

specific functions such as water treatment and desalination plant

is that they make perfect demonstration projects in which the

benefits of renewables can be immediately seen. In an industry

that needs to boost its profile, demonstrate effectiveness and

encourage greater investment, this is exactly the kind of venture

that developers like. It creates something of a virtuous circle

where greater investment leads to greater penetration, which in

turn leads to lower costs which encourages further deployment.

There is no one easy answer to

the world’s water problems. And certainly CPV does not provide

the complete solution. But it does tick a lot of immediate boxes,

and could play a significant role in ensuring that clean, healthy

water doesn’t become the preserve of the wealthy few. But more

than that, it opens the door to a whole host of other renewable

energy alternatives.



Water may look clean, but it can host harmful microbes that

cause illnesses. It's easy to purify water, however, with simple

materials and solar power. Solar

water purification system is a water purification system at

household level based on solar radiation treatment and water

distillation with additional use of solar heating. It is a

combination of two water purification processes, the Solar Water

Disinfection System (SODIS)and the solar distillation process.

Since SODIS, initiated by Professor Aftim Acra, is only ideal to

disinfect small quantities of low turbidity, micro-biologically

contaminated water, a solar heated still is added to the system

to address the issue of heavily contaminated water( such as sea

water, water with high turbidity and water contaminated by heavy

metal or pathogenic microorganisms).

For the cases where low turbidity water is not available,

contaminated water will be distilled to drinking water using the solar

heated still to remove any non-volatile solid impurities such as

salts, sediment, heavy metals and microorganisms. Water from some

wells or rivulets may be visibly clear, but it may not be drinkable

since the water may still contain pathogenic microorganisms. To solve

this problem, the contaminated water would be contained in clean,

transparent bottles and are exposed to the sunlight for a certain

amount time (depending on the intensity of the sunlight) allowing the


http://en.wikipedia.org/wiki/Microorganisms

http://en.wikipedia.org/wiki/Turbidity

http://ddc.aub.edu.lb/projects/health/solar-water/acra.html

http://www.sodis.ch/

http://www.sodis.ch/


solar radiation to deactivate any waterborne pathogens in the

contaminated water. Solar water disinfection is an effective way to

disinfect drinking water as it is recommended by World Health

Organization. The solar water purification system uses only solar

energy and can be built using recycling materials, thus, the system is

environmentally sustainable.

Principle Water

distillation is a physical process that filter solid impurities

out of fluid based on the difference in the volatility. At a

given temperature and pressure, substances with higher volatility

(water in this case) vaporizes more readily than the

substances(solid impurities) with lower volatility. The water

vapor is then directed to a cool region which condenses the water

vapor back to liquid state, leaving all the non-volatile solid

impurities such as salts, sediment, pathogenic microorganisms and

heavy metals behind. However, the distilled water may not be

suitable for drinking since it may still contain some volatile

organic compounds. The rate of vaporization is proportional to

the vapor pressure, fluid surface area and the fluid temperature.

The principle of SODIS is based on Ultraviolet water

treatment . It uses two components of the sunlight for the water


http://www.appropedia.org/Uv_water_treatment#Aftim_Acra_.26_SODIS

http://www.appropedia.org/Uv_water_treatment#Aftim_Acra_.26_SODIS

http://en.wikipedia.org/wiki/Volatile_organic_compound

http://en.wikipedia.org/wiki/Volatile_organic_compound

http://en.wikipedia.org/wiki/Volatility_(physics)

http://www.who.int/en/

http://www.who.int/en/

http://en.wikipedia.org/wiki/Waterborne_diseases


disinfection process :Ultraviolet radiationand infrared

radiation. UV-A radiation(wavelength 320-400 nm) interacts with

the DNA, nucleic acids and enzymes of the organic cell, destroys

the cell molecular structures which leads to cell deaths. UV-A

radiation also reacts with oxygen dissolved in the water

producing highly reactive forms of oxygen (oxygen free radicals

and Hydrogen peroxide], that can help the germicidal process.

Infrared radiation is a long-wave form of sun radiation, it can

be felt as heat, as it is responsible for raising the fluid

temperature. Studies had proven that 99.9% of microorganisms in

the water are eliminated if the water is heated to 50-60°C for

one hour. In order to disinfect contaminated water for drinking

effectively, it is recommended to expose the contaminated water

to full sunlight using clear PET bottles for 6 hours.If water

temperatures exceed 50°C, one hour of exposure is sufficient to

obtain safe drinking water.When the weather is cloudy for more

than 50% , the contaminated water need to be exposed for 2

consecutive days. The treatment efficiency can be improved by

raising the fluid temperature and exposing the contaminated water

to additional reflecting surfaces such as aluminium or corrugated

iron sheets.


http://en.wikipedia.org/wiki/Hydrogen_peroxide

http://en.wikipedia.org/wiki/Infrared_radiation

http://en.wikipedia.org/wiki/Infrared_radiation

http://en.wikipedia.org/wiki/Ultraviolet


Solar Energy Collector

The idea is first developed by Cansolair Inc., converting

solar energy to house heating energy using aluminum can. Solar

energy collector is composed of columns of painted black aluminum

can, a frame to house the columns and a ventilation for the heat

transportation. Before all the cans are glued together to form a

collected column, the top and the bottom of aluminum can is

needed to be removed. When placed under the sunlight, the columns

absorb the solar radiation and heat is convected to the air

inside the columns. Due to difference in the air density , warm

air would raise to the top of the columns and cool air would be

sucked into the columns from the bottom. The warm air flow is

then collected at the top of the columns. The columns are painted

in black to enhance the radiation absorbability and the size of

the columns can be varied for different requirement. Note that

the total height of the column is not equal to the sum of exact

height of each can since aluminum cans are designed to fit on top

of each other with use of groove.

Solar Distillation System

Solar distillation system is composed of a vaporizer that

holds the water, a vapor condenser that collects and condenses


http://www.cansolair.com/


steam and a water collector that collects distilled water. The

rate of vaporization is proportional to the fluid surface area

and the fluid temperature. The improve the performance of the

still, the vaporizer should be made as large as possible. Also,

at the bottom of the vaporizer, there are some serpentine gas

channels where warm air flow from the solar energy collector is

directed into. Due to the temperature difference between the

water and the air flow, heat is transfered into the vaporizer,

causing the water temperature to raise, thus, speed up the

vaporization process. Other methods such as using thermal

conductive materials, painting the vaporizer to black and using

some reflective surfaces to concentrate the radiation can be used

to improve the performance of the system.

Solar water disinfection system

To improve the efficiency of solar water disinfection system

, reflective surfaces can be used to intensify the solar

radiation toward the contaminated water. Another way to improve

the system performance is to increase the fluid temperature.

According to study, if water temperatures exceed 50°C, one hour

of exposure is sufficient to obtain safe drinking water. This is

when the solar energy comes in place. A portion of the thermal



energy collected from the solar energy collector is directed to

the heat up the bottled water.

SODIS Water Bottle Disinfecter

This method, while simple, is effective enough to be used

around the world. To disinfect water with the SODIS method, pour

untreated water into a clean, clear, plastic bottle and leave it

in the sun for at least six hours. It will heat up enough to kill

all the germs in the water, making it safe to drink.

There are concerns about this method. Some plastic bottles

may leach toxic chemicals into the water. In addition, the source

water must be relatively clear for solar pasteurization to work.

Nonetheless, the SODIS method is considered safe to use and has

saved lives in many regions that do not have access to clean

water.

Solar Box Method Solar

box cookers are easy to make and can be used to cook food as well

as to purify water. You will need two cardboard boxes, one of

which fits inside the other with about an inch of space on all

sides. Paint the inside of the smaller box black. Line the larger

box with newspaper for insulation, and place the smaller box

inside. Paint the outside of a covered pot black, and fill it



with water. Place it inside the black box, and cover the box with

plastic or clear glass. Leave the box in the sun for a few hours.

It will heat the water enough to kill any microbes.

This method can pasteurize a gallon of water in about three

hours in a sunny climate, according to SolarCooking.org. The

water must reach 150 degrees Fahrenheit and stay at that

temperature for a few minutes. This method, unlike the solar

still, doesn't remove chemical contaminants.

Design and Compare Water Purifying Methods

Design and compare three systems of water filtration. A

simple idea would be to compare bottles of water that have been

boiled, filtered through a cloth and ionized. Then test the pH

balance of the water to determine which method is most effective.

At higher grade levels, use more advanced filtration methods such

as reverse osmosis and carbon, and ultraviolet purification

systems.

Desalinization vs. Recycled Water

Using recycled water continues to be controversial in many

countries, and drought-stricken nations such as Australia have

long debated the high costs of desalinization. Conduct an



experiment wherein waste and salt water are treated with these

methods. Test both of these samples for their "purity," meaning

the presence of micro-organisms and bacteria, acidity, coloration

and even taste. Look further into the costs of each technique and

analyze the pros and cons of both.

Cost

Using solar energy as a source of power for products is

currently high on absolute costs compared to other sources of

power, say coal or kerosene in some states. Potential users of

solar water purification systems find themselves unable to pay

the full price of the solar still as they simply can't afford the

higher up-front capital cost.

Evaluation issues

Even if the design experts of solar water purifiers are

fully experienced and possess the expertise in the topic of solar

water purification, a few of them can understand the conditions

under which these purifiers would work in a community. Only a

resident could tell if the purifiers were easy to use and what

could be done to improve it. Without such crucial inputs, the



spread of solar water purification methods is effectively

reduced.

Make a Water Filter

Water filters are typically made with plastic bottles or

containers, sometimes with tree bark. A water filtration project

may also call for activated charcoal, napkins or paper towels,

salt, coarse and fine sand, and cotton and/or pebbles. Non-

poisonous grass can be used for a mesh. Muddy or dirty water,

once filtered and running clear, is not necessarily bacteria

free.

Filter Particle Size

Sand particle size may affect the effectiveness of a sand

water filter. Grains should not be too soft or fine, nor should

they be too large. Grains of sand used in a water filtration

system should range from small to medium sized, and the larger

particles should be separated from the smaller particles. A

science project for kids to experiment with different types of

sand is to run "dirtied" water through them to see which sediment

size makes the clearest water. Dirtied water can be made up by

adding mud, cooking oil, or some other non-toxic contaminant.



Water Filtration and Purification

Clean water is a must for survival. Water that is free of

impurities and pollution is called potable water. Filtered water

is not bacteria-free and is still capable of making a person ill,

sometimes even fatally.

CHAPTER III

METHODOLOGY

A. Equipments and materials

5-gallon transparent plastic bucket



1-gallon glass jar

Transparent plastic sheeting

Masking tape

Nontoxic, waterproof glue

Saltwater or contaminated water

B. General procedure

1)Glue the weight to the base of your glass jar. The weight

will be submerged in water, so make sure that you are using

nontoxic, waterproof glue that is strong enough to hold both

the weight and the glass jar. If possible, find a cylindrical

weight that fits the base of your glass jar;

2) Place the glass jar (with weight attached) inside your 5-

gallon bucket. The jar should be centered on the floor of the

bucket, a few inches below the rim and should allow room for

the bucket to fill with water;

3)Fill the space around the jar with contaminated water or

saltwater. Make sure you are not putting any water inside the

glass jar; rather, between the outside of the jar and the walls

of the bucket. Imagine a moat around your jar. The weight

should hold the jar in place;

4)Cover the top opening of the bucket with transparent



plastic sheeting. Make sure your piece of sheeting is large

enough to fully cover the bucket's opening without leaving any

spaces through which water vapor could escape;

5)Secure the sheeting by looping masking tape around the

rims of the bucket. The sheeting should be tight, with only a

slight bit of give;

6)Place the weight in the middle of the plastic sheeting

over your bucket. The weight should slightly curve the plastic

sheeting downward toward the center;

7)Leave your bucket in an open area that gets a good amount

of sunlight. Solar energy will evaporate the water, which will

then condense on the plastic sheeting, roll down the curve

created by the weight, and drop into the glass jar, leaving

salt and solid contaminants in the bottom of the 5-gallon

bucket.

Operating Procedures

Glue the 1 lb. weight to the base of your glass jar



Place the glass jar (with weight attached) inside your 5-gallon

bucket.

Fill the space around the jar with contaminated water or

saltwater.

Cover the top opening of the bucket with transparent plastic

sheeting.

Secure the sheeting by looping masking tape around the rims of

the bucket.

Leave

your bucket in an open area that gets a good amount of sunlight.

CHAPTER IV

RESULTS AND DISCUSSIONS

In this study, the water turned out clear. The sun warmed

the water in the bowl until the water evaporated and became gas.



When the gas rose and hit the plastic, it condensed there in

dropets (just like water vapor condenses into clouds). The

droplets rolleddown the plastic toward the weight and eventually

fell into the glass (like rain falling from the sky). The salt

was left behind in the bowl, making the water in the glass pure

enough to drink.

CHAPTER V

CONCLUSION AND RECOMMENDATION

In conclusion, I know now for sure that water can be

purified using solar energy at a temperature less than boiling,



as I stated in my hypothesis. But I feel this area of research

needs to be recognized by more people. I think more testing is

needed for final results to this experiment. So, I hope, by my

investigation, I am able to educate these people that can not

afford purified water to realize that boiling is not the only

way. I want to help thesepeople by finding a new way to purify

their water through solar energy.

My design can be applicable to modern day water problems.

Because it is solar powered, my system can be deployed to remote

locations, that do not have a significant power source, to

provide fresh water from contaminated or other undrinkable water.

A current example is being contaminated by sea water, and there

is no fresh water to drink on the island. In addition, the

developed system can be deployed in disaster areas to provide

purified drinking water. Examples include flooding due to

moonsoons, or tsunamis. A pertinent example is the tsunami and

subsequent radioactive contamination of water sources.

Chapter VI

Recommendations

1.)The current investigation did not rely on detailed

calculations for the sizing of the condenser.improved



thermodynamic analysis will likely point to an increase in the

size of the condenser to improve efficienc.

2.)Increasing the evaporator contact area between the warmth

water and the air will likely improve the amount of water that

can be absorbed by the air at a given flow rate.

REFERENCES

http://www.solarknoxville.org/for-students/science-projects/

http://www1.eere.energy.gov/education/pdfs/solar_rainmachine.pdf


http://www1.eere.energy.gov/education/pdfs/solar_rainmachine.pdf