University of Idaho



Table of Contents

Entry Page Number

Executive Summary 2

Problem Definition 3

Background 3

Project Learning 5

Concept Development 9

Lever Pump Design 9

Final Design 12

Backup Plan 14

Product Description 14

Overall Product 14

Product Performance 15

User Interface 15

Filtration Standards 15

Technical Product Testing 16

Turbidity Testing 16

Biological Testing 21

Economic and Business Testing 25

Business Plan Executive Summary 27

Conclusions and Reccommendations 29

Acknowledgements 31

Appendices

Appendix A: Figures 32

Appendix B: Tables 36

Appendix C: Moringa Seed Experiment Procedures 39

Appendix D: Specifications Documentation 49

Appendix E: Needs/Conclusions Analysis 53

Appendix F: Team Assessment 55

Appendix G: Updated Experiments 61

Attached:

DFMEA

CWA Business Plan

***For latest laboratory results, see Appendix F***

Executive Summary

Team Clearwater Aid’s goal was to design, build, and test a portable water filter for the people of East Africa and other Third-World Countries. This filter aims to reduce the mortality rate related to drinking unsafe water and improve the overall quality of life around the globe. Currently 2,500 African children die each day (EPA), team CWA worked to develop a low-tech and sustainable solution to help solve this problem. In order to meet safe drinking water regulations, the water needed to have a turbidity less than 5 NTU and eliminate bacteria down to 0.2 microns.

Water filtration was broken into two categories: turbidity and bacteria. To reduce turbidity levels the team used African native, Moringa seeds. These seeds act as a coagulant and cause suspended particles to settle out of the water. To eliminate bacteria, the team used a coffee/clay ANU filter. Both of these methods were implemented in the team’s first design: the lever pump. This design was tested in Kenya in order to receive realistic testing feedback. The pump filter cleaned the water, but the design was too complex and unsustainable in rural areas. Team CWA performed an additional design iteration: the Moringa seed and ANU filter pot. Adding roughly 1 seed per liter of water, turbidity levels decreased from 400 NTU to less than 5 NTU in 8 hours. Microbial tests are still inconclusive. One test session proved that the 50/50 ANU filter removed all E. coli contaminants but two additional tests returned positive E. coli contamination. Additional testing with various coffee clay filters need to be performed before the ANU filter can be negated or accepted. While the new design is a more sustainable solution, additional testing needs to be performed in the future. This testing will produce a filter with optimal life and application.

Also, a business plan was written to develop Clearwater Aid Nonprofit Organization. This organization will provide funding for continual filter development and clean water solutions using students here at the University of Idaho.

Problem Definition

The filter designed by team Clearwater Idaho Aid must reliably produce clean water. Clean water is that which is free of all harmful viruses, chemicals, organisms and particulate. CWA has created several specifications that as goals that constitute a high quality filter.

• Water must be less than 5 NTU (EPA)

• Filter must have pore sizes no larger than .2 microns (Industry Std.)

• Filter has a flow rate greater than or equal to 1 Liter per minute (Industry Std.)

• The filter must be intuitively understandable to the pilot population: Maasai

• Filter must be implement able into Maasai culture

• The filter must be affordable to either the people or a small scale fund raising organization

As stated earlier, Turbidity is a measurement of the amount of particulate in the water. Turbidity samples are commonly measured by passing Infrared light through the sample at a given wavelength and measuring the scatter through the sample. The concluding measurement is given in Nephelometric Turbidity Units (NTU).

Filtering out chemicals and viruses is much more difficult. Although all microorganisms are larger than .2 microns in size, most viruses are not. This means that without chemical purifiers, no filtration system is completely effective and removing viruses.

Eric Morris desires a long term solution to this problem. In order to create design development that is robust and effective, the Maasai tribe must not only have an understanding of the filter, but ownership over the problem. For that reason, it is essential that the solution is not only sensitive to their culture and worldview, but also affordable so that a multitude of people may have one.

Background

An estimated 1.5 billion people remain without safe drinking water in the world. While the global picture is not encouraging, Africa is much worse. In Africa 2,500 children die each day due to water-borne diseases (EPA). Africa has a 6% infant mortality rate [CIA], and that number is as high as 10% in regions of East Africa. Many of the infant deaths are related to unclean drinking water. This problem is especially troubling for nomadic tribes, such as the Maasai.

Eric Morris, the project client, is a missionary who travels to East Africa annually. Eric works with the people living in the slums and nomadic tribes living in the country. From his numerous visits, Eric has seen the need for pure drinking water for the African people. He hopes to reduce the infant mortality rate and to help eliminate the danger of waterborne disease.

The Maasai’s situation is worse because traditional portable filtration methods are not able to handle the high turbidity of East African water. Turbidity is a measurement of the amount of suspended particulate in the water. Existing portable filter designs work but have a limited life because the amount of particulate in the water clogs the filter itself, rendering it useless. Furthermore, much of the advanced filtration information is proprietary, and not patented. Successful filtration methods, such as a sand filter, are not portable, limiting the access to clean water. There is a need for clean drinking water not only in Africa but also in other third world countries.

Solving the problem for the Maasai tribe would be a step toward solving the problem for countless other peoples. By generating a solution that was created in light of the customs, beliefs and education of the user, the effectiveness and reliability of the filter would be much greater. Eric Morris’ desire was to solve the problem with the Maasai, for the people and nothing else.

In order to solve the problem, it was essential that CWA understood much of the Maasai culture. Jenn Miller, a member of the Clearwater Idaho Aid, traveled with Mr. Morris to Kenya in February 2006 to test the team’s first prototype. Upon her return the team found the prototype too expensive and complex to be easily integrated into the society.

It is therefore necessary to develop and implement a sustainable, simple and cheap filtration process. This requires the team to design a simple, portable, reliable and safe filter that achieves industry specifications. That filter must also be cheaply available to native Kenyans.

Project Learning

“Safe” Drinking Water:

Safe water is water that is fit to drink for extended periods of time. Water that has a turbidity level higher than 5 NTU is not safe. In addition, according to the World Health Organization water must be filtered down to 0.2 microns in order to be safe drinking water. Furthermore, water which contains dangerous viral, microbial, or bacterial life is unsafe. Water which has been distilled of all minerals slowly leaches vitamins from the body and is therefore unfit for prolonged consumption. Water that has been purified through the use of chlorine or iodine is also unsafe if used for long periods of time.

Turbidity:

Turbidity is a measurement of the clarity of water. Turbidity is measured by passing light through a sample of water, and recording the deflection and magnitude on the other side. It is commonly measured in Nephelometric Turbidity Units. The proper methods for measurement of turbidity are found in ISO 7027. Turbidity measurements may be affected by various particle size, shape and reflectivity.

Contaminants:

East African water contains a number of contaminants. CWA’s goal is to focus on filtering out the microscopic pathogens. Microscopic organisms are organisms that are too small to be seen by the naked eye. They include protozoa, bacteria and viruses. These are the smallest of the pathogens and consequently the organisms of concern to the water filter project.

Protozoa are single celled, eukaryotic organisms. Eukaryotes are organisms whose cells have membrane enclosed organelles. Protozoa are the biggest of the three types of microorganisms mentioned above. They range in size from 1 to 150 um. Many protozoa are pathogens causing illnesses such as: Toxoplasmosis, Giardiais, Amebiasis, Cryptopoidiosis, and Traveler’s Diarrhea. Toxoplasmosis is caused by Toxoplasma gondii. This organism is most dangerous in people with weakened immune systems. It is transferred through cat feces, contaminated blood or meat, and in contaminated water. Giardiasis, caused by Giardia intestinalis, is transmitted by swallowing water and food that has come into contact with infected feces. It causes diarrhea and is resistant to chlorine. Amebiasis is caused by Entamoeba histolytica. This disease is very common in developing countries and is transmitted by coming in contact with food or water infected with feces. Crytopoidiosis is caused by Cryptosporidium parvum. This disease causes diarrhea and is also contracted by swallowing food or water that has come into contact with infected feces. This protozoan is also resistant to chlorine. Traveler’s Diarrhea is caused by Cylcosporidium cayetanensis, Entamoeba hestolytica, and Dientameaba fragilis among other causes such as bacteria and viruses.

Bacteria are single celled prokaryotic microorganisms. Prokaryotes are organisms that have no membrane enclosed organelles. Bacteria are the second biggest microorganisms mentioned above. They range in size from 0.2 to 10 um. Bacterial Pathogens cause Hemolytic uremic syndrome, Typhoid Fever, Cholera, and Traveler’s Diarrhea. Hemolytic uremic syndrome is caused by Escherichia coli O157:H7 from contaminated uncooked foods, raw milk and from manure contaminated sources. Typhoid Fever is caused by Salmonella enterica Typhi and can be transmitted through infected water or food ingestion infected from an infected person handling them or by contaminated water. Cholera is caused by Vibrio cholerae which is characterized by severe diarrhea. Traveler’s Diarrhea is caused by a number of bacteria including Escherichia coli, Campylobacter jejuni, Salmonella spp., Shingella spp., Vibrio spp., Aeromonas hydrophila, Plesiomonas shingelloides, and Yersina enterocolitica.

Viruses are infectious agents that are debatably either alive or not alive since they are biologically inactive and do not reproduce until they are in a host cell. They consist of a protein coat and DNA or RNA. These are the smallest of the pathogens concerned. Viruses range in size from 25 to 400 nm. These sizes are most likely not practical to filter. Some of the diseases caused by viruses include Hepatitis A, Norovirus, and Polio. Hepatitis A can be transmitted person to person, through water, and food that has come into contact with sewage and causes liver damage. Norovirus is transmitted fecal to oral and causes gastroenteritis. Polioliomyelitis (Polio) is acquired by fecal to oral or oral to oral transmission and causes aspeptic meningitis and paralysis.

Purification:

Boiling:

Boiling kills most, but not all bacteria. It takes approximately 3 minutes for water at boiling temperatures to be effective. Furthermore, there are a number of parasites that are not affected by boiling. Boiling does not remove particulate or chemical pollutants.

Chemical

Chemical treatment does not remove particulate, but does reliably kill all viruses and bacteria found in the water.

Iodine

Iodine is an affective method of killing viruses. The colder the water that is being used, the longer the time iodine requires. It is extremely dangerous for women with thyroid problems. It should not be used by anyone more than 3 consecutive times. Iodine also leaves an unfavorable taste in the water.

Chlorine

Chlorine is similar to iodine. It is extremely poisonous if used incorrectly. It also should not be used consecutively for any amount of time.

Advanced water filtration methods

Activated Carbon is actually an absorption purification method. Carbon not only removes most bacteria, but also removes unpleasant tastes and odors from the water. It is formed by subjecting oxygen deprived charcoal to superheated steam. Activated Carbon is currently used in East Africa for other medicinal purposes, and is native to the area.

Reverse Osmosis uses electrical power to push water through a permeable layer, and separate it from the more dense particulates. It is one of the most reliable methods of water filtration. Reverse Osmosis requires advanced materials, and facilities. The parts which constitute a Reverse Osmosis filter also must be replaced frequently.

Ceramic filters are commonly used in destitute regions throughout the world. Ceramic filters are sturdy, reliable and safe. Furthermore, the filter may be impregnated with a colloidal silver to reduce bacteria growth within the filter itself.

Sand filtration is a proven method. A layer of sand is placed on top of gravel, and covered with approximately 18 inches of water. Under those conditions, it takes about 2 weeks for a biological layer forms over the sand. This layer helps absorb and filter out may harmful contaminants. The amount of sand necessary, and the stability required for the biological layer make a sand filter only feasible as a permanent fixture.

The Australian National University Filter consists of clay and coffee grinds that have been fired with cow manure. This filter was recently presented by an ANU doctor. No formal data has been presented to verify the effectiveness of the filter.

Relevant Domestic Facts:

A large amount of the aid is provided by Christian churches that are domestic, and abroad. This has created a trust between the churches and people of all beliefs. Furthermore, the native church leaders are the respected teachers of each tribe and are continually trusted for wisdom.

The area of East Africa has some relevant natural resources. Kenya exports large amounts of coffee, tea and charcoal. Much of the soil is terra cotta clay. The pilot population, the Maasai tribe, is a cattle herding people and use manure for everything from fuel to building.

An additional resource which is native to Africa is the Moringa Tree. This tree’s seeds can be used as a flocculent to settle suspended solids in water. In addition to the seeds water filtration applications, the tree leaves are highly nutritional. One teaspoon of leaf powder contains more protein than a steak and 100% daily value of vitamins A and C. The tree takes between two and three years to mature, and the seeds grow in large pods containing about 15 Moringa seeds.

Concept Development

The team initially started with three concept designs at the end of phase three: the lever pump, the press pump filter, and the slow sand filter. Of these three designs the lever pump filter was chosen as the final design to construct and test. The lever pump filter was successfully constructed and produced clean drinking water; however, on-site testing in Africa presented many improvements. Team Clearwater Aid decided to perform an additional design iteration for their final design: the coffee/clay pot and Moringa seed filter.

Brainstorming &Concept Design

In order to generate optimal design solutions for the filter, team CWA held multiple brainstorming sessions. These meetings focused on developing ideas for individual filter functions: turbidity reduction, bacteria removal, and pump mechanism. These individual functions were then evaluated by the team and exemplar ideas were then incorporated in full system design ideas: the lever pump, the press pump, and the slow sand filter.

Original Design- The Lever Pump [FIG 1]

Turbidity Filtration

The turbidity filtration process starts by mixing one crushed Moringa seed per one liter of water, for five minutes, and letting the water sit for two hours. The Moringa seeds act as a flocculent, ionizing the suspended particles and causing them to attach to each other. When the particles clump, they become heavier and settle to the bottom of the container. The African people can add these crushed seeds to their water collected and once the mixing and settling process is complete they can pour from the top of the water container, leaving the settled particles at the bottom. Following the Moringa seed process the water travels through a holed PVC tube wrapped with polar fleece. This fleece acts as an additional turbidity screening to ensure that all large particles are filtered before the microbial filter.

Pump Mechanism

The hand pump for the filter works similar to that of a bike pump. On the upstroke of the pump water is sucked into the first check valve and flows into the pipe system. On the down stroke of the pump, the first check valve closes, and water is pushed through the second check valve and through the microbial filter. This process is continually repeated until enough water has been supplied. The pump mechanism seals inside PVC piping using cow hide. The leather expands once it’s contacted with water and seals the tube to give enough force to push the water through the microbial filter.

Microbial Filter

The microbial filter is responsible for removing harmful bacteria that are prevalent in the water and cause disease. These pathogens can be extremely small (0.2 microns) and are difficult to filter out of water. This design’s microbial filter uses technology developed at the Australia National University (ANU). The ANU filter uses coffee grounds and clay for its construction. Equal amounts of the coffee grounds and clay are mixed together and made into disks. The filters are left to dry and then are burned for an hour using a fuel source such as manure. The coffee grounds are burnt out of the filters, leaving small pours to filter out the bacteria from the water.

The microbial filter is encased in PVC hosing and is sealed using rubber O-rings. Ceramic filters commonly need around 70 psi (pounds per square inch) pressure force to push the water through the filter.

Figure 1: Lever Pump Design

Overall Mechanism

The entire filter uses basic construction materials or natural resources that are abundant in East Africa. The parts are PVC tubing, washers, nuts, a thread rod, two check valves, and a five gallon bucket to encase the entire filter. The filter is extremely portable weighing about five pounds. The main casing parts are expected to last around six to twelve months, and the polar fleece and microbial filter will need to be changed out weekly. Each filter will provide water for around six people.

Testing & Iteration

The lever pump was fully built and then later tested in Africa. In order to receive complete feedback from the end users of the filter, team member Jenn Miller traveled to Nairobi, Kenya. While there, the filter was tested in the Ngong Hills, outside of Nairobi, with the Maasai Tribe. The initial water conditions had turbidity levels around 900 NTU. Moringa seeds were crushed and added to the collected water (1 seed per liter of water). The Moringa powder and water mixture was stirred with a stick for five minutes and then sat for an hour and a half. After the water settled, the turbidity levels were roughly 60 NTU. Passing the water through the pump filter, pouring from the top of the collected water, water came out of the filter at 2 liters per minute. The final measured turbidity level was 0.35 NTU. Bacteria tests could not be performed due to hazards of transportation of the water and time effects.

While in Africa, Miller solicited advice from many aid workers and local citizens. Assessment of the filter design and use inspired many suggestions for future iterations.

- The pump mechanism is too complex for simple assembly

- The pump mechanism requires too many parts for a sustainable filter

- The filter should be easy to assemble and construct

- Filter cost has to be relatively close to free

- The filter needs to be able to be constructed by local people in order to build ownership and responsibility to ensure the filters use

- The filter needs to be promoted to the local communities

- Education about water filtration and disease needs to be taught along with the water filtration process

- The water must have a pleasant taste (“tasteless”)

- The filter needs to be developed further so that its technology can apply to large scale stationary communities and nomadic lifestyles. (Scalable)

- Providing filters to communities will not work because this does not develop community ownership. This does not promote a long term solution.

Final Filter Design—Moringa Seeds and Coffee Grounds/Clay Pot [FIG. 2]

Using the feedback that Miller brought back from her testing in Africa, team Clearwater Aid performed one more filter design iteration. This began with a focused brainstorming session which brought forth the final design: Moringa seeds and coffee grounds/clay pot design. This design was then built and tested against project specifications. These results are shown in Table 1.

[pic]

Figure 2: Coffee/Clay Pot Design

Table 1A: Qualitative and Quantitative Lever-Pump Filter performance

|Specification |Quantity |Pump Filter |Spec. Met? |

| | |Capability |(Yes/No) |

|Bacteria Filtration |< 0.2 Microns |Unknown |No |

|Flow Rate |> 1 L/min |2 L/min |Yes |

|Turbidity Reduction |< 5 NTU |0.35 NTU |Yes |

|Cost |< $5.00 |$35.00 |No |

|Native Materials |N/A |No |No |

Future Design Improvements

Team Clearwater Aid foresees filter improvements for future project teams. The filter has multiple areas of research and testing that need to be performed.

- Verification of coffee/clay filter’s capability to remove harmful bacteria

- Filter output and flow-rate optimization

- Filter scalability

- Optimization of filter size and shape

- Filter use process (make compatible with African lifestyle)

- Possible use of other materials, such as tea in filters

Table 1B: Qualitative and Quantitative Final Filter performance

|Specification |Quantity |Coffee/Clay & Moringa Capability |Spec. Met? (Yes/No) |

|Bacteria Filtration |< 0.2 Microns |Unknown |No |

|Flow Rate |> 1 L/min |.9 cups/hr |Yes |

|Turbidity Reduction |< 5 NTU |3.6 NTU |Yes |

|Cost |< $5.00 |< $4.50 |Yes |

|Native Materials |N/A |Yes |Yes |

Backup Plan

There are some precautionary measures that would ensure safe water from the filter if not all contaminants are removed. With modern water treatment facilities, disinfection finishes the treatment process to ensure the microbial contaminants are killed. Disinfection is also possible for our design. Using some inexpensive chlorine tablets, which are commonly used by backpackers and campers, would ensure the safety of the water from our filter. The most important aspect of the project is to provide safe water to drink. Although this option increases the cost of the product, it would provide safe water. Chlorox bleach droplets can be used to disinfect water bacteria. Another possible option would be to boil the filtered water to kill the remaining organisms. This does require time, fuel, and energy, but it would result in safe water.

Product Description [FIG 2]

The final filter design from Team Clearwater Aid is simple, lightweight, portable and easily fabricated. Instead of one more complicated filtration apparatus, the team developed a two part system, requiring only buckets, and the ANU filter. This requires that the user own a bucket, but allows the user to fabricate a filter in a matter of hours.

Furthermore, the ability for end-user fabrication consequently creates end-user ownership. The native population will be able to solve their own problems through following the education provided by the Clearwater Aid team, and subsequently their village leaders.

The final product therefore meets all of the client’s needs, and fulfills some wants. The filtration system is as it is: (1) simple, (2) renewable, (3) portable, (4) teachable, (5) given to ownership, (6) natively fabricate able, (7) not a chemical solution, and (8) created with solution to the greater worldwide need in mind.

Overall Product:

The filtration process begins by mixing a flocculent with the collected water. The flocculent used is the crushed Moringa seeds, as discussed in the Concept Development Section. The powder is mixed with the water at a ratio of 1 seed to 1 liter water. Once the water has been left for a number of hours, most of the particulate should be settled on the bottom of the bucket. That water is then carefully pulled into the filter.

The filter consists of a filtering median that has been shaped into a bowl and placed on top of a common 5-gallon bucket. The median is a mixture of 1 gram coffee grounds (or tea grounds) to 1 gram terra cotta clay. The mixture is shaped into a bowl, and then fired at an extremely high heat. The firing may be done in a kiln, a wood fire, or a fire that is fueled by manure. It then must be flushed with water once, before it is ready for use.

Product Performance:

The turbidity flocculent of Moringa seeds have longed been used in other applications. Moringa seeds have been used medicinally, and the tree itself is used as a major source of protein. When pounded into powder, the natural charge of the seeds attracts dirt and biological matter. This then, increases the mass of each individual particle. The increased mass means that a larger percentage of the particulate is no longer able to remain suspended within the water and therefore settles to the bottom.

The ANU is a relatively new discovery, and therefore much of the method to its success is still unknown. As top institutes and universities around the world are gathering data on its performance, it is believed that its primary mode of water cleansing is through filtration. This is done because the coffee grounds are being burnt out at the high firing heat, leaving micro-pores which do not allow any of the biological matter through.

User Interface:

As stated, the natives of Kenya would be able to construct this filter using the resources around them. Because the religious leaders are so trusted, once they are educated, the villages will begin to be able to sustain themselves with clean water. The Maasai tribe could use the quickly replenishing Moringa tree, and the very earth under their feet to make their filter molds. Once those are made, the Maasai cattle men can build up fires using the abundant cow manure and then fire their filters. This is advantageous as it not only allows for the people to create new filters at any time, but also teaches an aspect of ownership and renewability.

Filtration Standards:

The filtration system itself does make a few sacrifices to ensure end-user impact. Testing is still ongoing to determine the filter median life, however ease of fabrication may alleviate concerns to shortened filter life. Also, although the “Lever-Pump” design exceeded industry standards of chamber pressure and flow rate, the current design offers little user control over filter flow rate. Initial microbial tests have been negative to E. coli contamination, but more tests must be performed to ensure that the filter is completely reliable.

Technical Product Testing

As stated earlier, the filtration performance was separated into two major categories 1) Turbidity filtration using Moringa seeds, and 2) Microbial filtration. These were addressed because of the CWA redesign, solved many of the weaknesses illustrated by the DFMEA, but not these concerns. [Appendix E] The following section discusses the laboratory results for each section.

Moringa Seed Testing and Analysis

The first information needed was how efficient Moringa seeds were at reducing turbidity. The focus of the initial testing was to determine the flocculation efficiency of Moringa seeds, and compare the Moringa seeds to a common water treatment coagulant, alum (aluminum sulfate). To test the efficiency, the experiment was setup similar to a Jar test, which is a common flocculation test and determining optimal doses for the coagulant. The beakers were placed on a large stir place with 5 sites to uniformly stir the mixtures. The seeds were crushed to powder and specific quantities measured to achieve predetermined concentrations of 0.5, 1.0, 2.0, and 4.0 g/L. The alum quantity was measured for 0.15 g/L concentration. The coagulant quantities were mixed into turbid water from Paradise Creek, which consisted of both colloidal and settleable particles. The initial average turbidity was 95 NTU. These beakers were stirred for 20 minutes, and allowed to settle for 1 hour. A control beaker with no coagulant was set aside for comparison.

During the stirring, it was observed that the alum was flocculating well and clearing up the water. The Moringa seeds did not exhibit much difference. After stirring, the alum settled quickly showing a significant visual difference in water clarity. The four Moringa seed mixtures started to show improvement, compared to the control, during the settling period. The Moringa seed concentrations of 0.5 g/L and 1.0 g/L were flocculating the best, which suggested the lower concentrations were more effective. With this in mind, another mixture with a concentration of 0.2 g/L was setup.

Turbidity measurements were taken after the 1-hour settling period. The average turbidity ranged from 16.36 NTU for 0.2 g/L Moringa seed mixture to 58 NTU for the control. There were issues with the turbidimeter with inconsistent measurements and reading values that were visually wrong. This was due to operator and equipment error. By visual observation, the concentrations were ranked in the following order, starting with the best: alum, 0.2 g/L, 0.5 g/L, 1.0 g/L, 2.0 g/L, 4.0 g/L, and control. These results suggest the Moringa seed is an adequate coagulant, but not as efficient as alum.

The mixtures were left to sit overnight for 2 days (approximately 44 hours after initial testing began). There were significant improvements in both the alum and Moringa seed water mixtures. The average turbidity measurements ranged from 4.24 NTU for 0.2 g/L Moringa seed mixture to 32.95 NTU for the control. Again, error with the turbidimeter occurred, and by visual observation, the alum mixture was clearer than 0.2 g/L Moringa seed. The visual rank of the concentrations was the same as before, except the 2.0 and 4.0 g/L were approximately the same. From these results, it was concluded Moringa seeds are as efficient as the standard alum, although the process is slower and the seed mixtures need more time to settle out the particles. It was determined one Moringa seed had an average of 0.173 g of powder, suggesting one Moringa seed per liter would be a necessary dose, which is an easy, friendly measurement.

It is not realistic for people in Africa to use a stir plate to mix the Moringa seeds into turbid water. The practical use of the Moringa seed needed to be tested. From the previous experiment, it was observed that the seeds were a little moist. Another goal of this experiment was to determine if dried seeds worked better than the regular, non-dried seeds. To dry the seeds, they were placed in an oven at 98°C for 50 minutes. Each of the regular and dried seed powder quantities were measured to obtain three predetermined concentration mixtures of 0.1 g/L, 0.2 g/L, and 0.5 g/L. The powder was mixed with Paradise Creek water with an average turbidity of 326.3 NTU. For the practical use procedure, each water sample was stirred with a stick for 5 minutes, and the left to settle. A control of untreated water was also prepared.

After 1 hour of settling, the average turbidity ranged from 21.48 NTU for the regular seed concentration of 0.1 g/L to 237.67 NTU for the control. As seen in Table 3 the Moringa seed significantly reduced the turbidity. The control did not settle much, suggesting the water sample contained more colloidal particles than those that can be settled. Something did not work well for the 0.2 g/L regular seed. It should have been less turbid. By visual observation, the concentrations were ranked in the following order, starting with the best: 0.1 g/L regular, 0.5 g/L regular, 0.5 g/L dried and 0.1 g/L dried, 0.2 g/L dried, 0.2 g/L regular, and control. The turbidities were comparably similar, except the 0.2 g/L regular seed and the control. This suggests the dried seeds do not improve the flocculation efficiency.

The samples were left over night to settle (approximately 18 hours after initial testing began). The average turbidity ranged from 1.26 NTU for the 0.5 g/L dried seed to 139.33 NTU for the control. By visual observations, all six looked similar and no visual difference in turbidity between them. As seen in Figures 3, the decrease in turbidity was significant during the first hour and then gradually continued to decrease. With the similar results and no significant differences between the dried and the regular seed, it will be more practical and easier for the African people to use the Moringa seeds without drying. The simply procedure of stirring with a stick for five minutes and leaving the water to settle worked well, reducing the initial turbidity of 326 NTU to less than 5 NTU.

Table 3: Turbidity Measurements from Experiment 2: Practical Use.

A) Turbidity measurements for control;

B) Turbidity measurements for the regular, non-dried moringa seeds; and

C) Turbidity measurements for dried moringa seeds.

A)

|Control |Turbidity (NTU) @ t = 1 hr |Turbidity (NTU) @ t = 18 hr |

| - |

|Concentration (g/L) |Turbidity (NTU) @ t = 1 hr |Turbidity (NTU) @ t = 18 hr |

|  |

|Concentration (g/L) |Turbidity (NTU) @ t = 1 hr |Turbidity (NTU) @ t = 18 hr |

|  |1 |2 |3 |

|Bacteria Filtration |< 0.2 Microns |Unknown |No |

|Flow Rate |> 1 L/min |.9 cups/hr |Yes |

|Turbidity Reduction |< 5 NTU |3.6 NTU |Yes |

|Cost |< $10.00 |< $10.00 |Yes |

|Native Materials |N/A |Yes |Yes |

Table 2: Lever Pump BOM

Table 3: Turbidity Measurements from Experiment 2: Practical Use.

A) Turbidity measurements for control;

B) Turbidity measurements for the regular, non-dried moringa seeds; and

C) Turbidity measurements for dried moringa seeds.

A)

|Control |Turbidity (NTU) @ t = 1 hr |Turbidity (NTU) @ t = 18 hr |

| - |

|Concentration (g/L) |Turbidity (NTU) @ t = 1 hr |Turbidity (NTU) @ t = 18 hr |

|  |

|Concentration (g/L) |Turbidity (NTU) @ t = 1 hr |Turbidity (NTU) @ t = 18 hr |

|  |1 |2 |

|  |1 |2 |3 |Average |1 |2 |3 |Average |

|Turbid Water |241 |237 |235 |237.67 |140 |139 |139 |139.33 |

|DI Water |0.05 |  |  |  | 0.04 |  |  |  |

|Regular Moringa Seeds |

|Concentration (g/L) |Turbidity (NTU) @ t = 1 hr |Turbidity (NTU) @ t = 18 hr |

|  |1 |2 |3 |Average |1 |2 |3 |Average |

|0.1 |23.43 |20.11 |20.91 |21.483 |2.70 |2.29 |2.16 |2.383 |

|0.2 |51.00 |49.92 |46.62 |49.180 |2.96 |2.85 |3.08 |2.963 |

|0.5 |37.84 |32.92 |33.71 |34.823 |2.48 |3.33 |3.23 |3.013 |

|Dried Moringa Seeds |

|Concentration (g/L) |Turbidity @ t = 1 hr |Turbidity @ t = 18 hr |

|  |1 |2 |3 |Average |1 |2 |3 |Average |

|0.1 |36.13 |32.22 |34.11 |34.153 |2.59 |2.61 |2.55 |2.583 |

|0.2 |30.36 |28.84 |28.26 |29.153 |2.34 |2.48 |2.41 |2.410 |

|0.5 |34.40 |37.48 |36.00 |35.960 |0.89 |1.16 |1.74 |1.263 |

[pic]

[pic]

Moringa Seed Experiment

Trial 3

3/29 – 3/30/06

Goal: To compare the flocculation capabilities of the Himalayan and African native moringa seeds under practical use application and determine the optimal settling detention time.

Procedure:

1. Crushed two types of seeds to a powder, both the Himalayan (India) and African native, with mortar and pestle

2. Measured the initial turbidity of the moderately high turbidity samples from Paradise Creek

3. 500 ml of turbid water measured into five 600 ml beakers: 4 experimental (2 for each of the India and African seeds) and 1 control

4. Measured the moringa seed quantities with analytical scale for the determined two concentration amounts: 0.1 g/L, and 0.25 g/L

5. Added the measured crush seed powdered into the designated beakers and stirred with a stick for 5 minutes; repeated for each beaker except the control

6. Let the water-moringa seed mixture sit for approximately 2 hours and 20 minutes

7. Measured the turbidity for each sample and recorded the data

8. Let the water-moringa seed mixture sit for an additional 3 hours and 20 minutes (approx. 5 hours and 40 minutes total)

9. Measured the turbidity for each sample and recorded the data

10. Let the water-moringa seed mixture sit for an additional 2 hours and 20 minutes (approx. 8 hours total)

11. Measured the turbidity for each sample and recorded the data

12. Let the water-moringa seed mixture sit overnight (approx 25 hours and 30 minutes total)

13. Measured the final turbidity for each sample and recorded the data

Results/Conclusions:

Initial Turbidity average: 299 NTU

Average African moringa powder in one seed: 0.266 g

Visual Observations:

• Himalayan/India native seeds: small seeds, round, cream color powder, used for the previous 2 moringa seed experiments

• African native seeds: large seeds, oval shape (football shape), yellowish color powder

• After 2.3 hours, the India native seed-mixture looks a little clearer than the water with the African seeds. The Africa seed water has a little bit of white coloration, especially the 0.5 g/L

• The type of Paradise Creek water used has several settleable particles, so the control has done better than the other controls in the previous experiments

• After 2.3 hours, visually the concentrations were ranked in the following order starting with the best and decreasing in quality: 0.2 g/L India, 0.5 g/L India, 0.2 g/L Africa, 0.5 g/L Africa, and control.

• After 2.3 hours, based on the NTU measurements, the concentrations were ranked in the following order starting with the best and decreasing in quality: 0.2 g/L India, 0.2 g/L Africa, 0.5 g/L India, 0.5 g/L Africa, and control.

• After 5.6 hours, visually the concentrations were ranked in the following order starting with the best and decreasing in quality: 0.2 g/L India and 0.5 g/L India, 0.2 g/L Africa, 0.5 g/L Africa, and control.

• After 5.6 hours, based on the NTU measurements, the concentrations were ranked in the following order starting with the best and decreasing in quality: 0.2 g/L India, 0.5 g/L India, 0.2 g/L Africa, 0.5 g/L Africa, and control.

• After 8 hours, visually the concentrations were ranked in the same order as previous.

• After 8 hours, based on the NTU measurements, the concentrations were ranked in the same order as previous (0.2 g/L India, 0.5 g/L India, 0.2 g/L Africa, 0.5 g/L Africa, and control).

• India native seeds appear to do better than the African native seeds

• After 25.5 hours, visually the concentrations were ranked in the following order starting with the best and decreasing in quality: 0.2 g/L India, 0.2 g/L Africa and 0.5 g/L India all about the same, 0.5 g/L Africa, and control.

• After 25.5 hours, based on the NTU measurements, the concentrations were ranked in the following order starting with the best and decreasing in quality: 0.2 g/L Africa, 0.2 g/L India, 0.5 g/L India, 0.5 g/L Africa, and control.

• It appears the African seeds are more sensitive at higher concentrations, but does just as well as the Himalayan seed at lower concentrations.

• The control did better than the previous controls because this water sample had more settleables than the other experiments.

|Control |Turbidity @ t = 2.3 hr |Turbidity @ t = 5.6 hr |Turbidity @ t = 8 hr |Turbidity @ t = 25.5 hr |

|  |1 |2 |Average |1 |

|  |1 |2 |3 |Average |

|1 |  |Purity of water filtered |1 |micron |

|2 |  |Portability |1 |None |

|3 |  |Time to replace filter (Maintenance) |2 |min |

|4 |  |Level of turbidity filter can handle |2 |units? |

|5 |  |Filter dimensions |2 |M |

|6 |  |Weight of filter |3 |kg |

|7 |  |Tools required for maintenance |3 |list |

|8 |  |Rate of filtration |3 |Gal/min |

|9 |  |Material accessibility |3 |  |

|10 |  |Life of the filter |3 |Gal |

|11 |  |Ease of use |3 |  |

|12 |  |Lab tools needed for water testing |4 |list |

|13 |  |Durability |4 |  |

|14 |  |Time to assemble |5 |min |

|15 |  |Nozzle size |5 |M |

|16 |  |Inlet size |5 |M |

2. Gather benchmarking information.

a. compare filter against other filters available (Canadian filter?)

3. Set ideal (challenging) and acceptable target values.

|Metric |At Least |At Most |Between |Exactly |

|Purity of water filtered | 0.0002mm |  |  |  |

|Portability |  |  |  | Adult |

|Time to replace filter (Maintenance) |  | 1 hr |  |  |

|Level of turbidity filter can handle |  |  | | Any |

|Filter dimensions | Transportable |  |  |  |

|Weight of filter |  | 40 lbs |  |  |

|Tools required for maintenance |  |  |  | None |

|Rate of filtration | 125 Gal/ Day |  |  |  |

|Material accessibility |  |  |  | Available |

|Life of the filter | 2 years |Infinite |  |  |

|Ease of use | 10 years old |Anyone |  |  |

|Lab tools needed for water testing |  |  |  | N/A |

|Durability | Wear and Tear |Not too heavy |  |  |

|Time to assemble |  | 3 hrs |  |  |

4. Align with needs.

[pic]

5. Complete the target specs document

[pic]

6. Dialogue with client

7. Iterate

Stage 3: Assess Performance & Complete This Task

1. Assess Team Performance

a. Identify strengths

i. broad view of the specifications required

ii. numerical values and units

iii. fulfilling needs, defining them with the specs

b. Identify improvements in future performance

i. Break apart specs created by “needs” and “wants”

ii. Have more specifications

c. List insights

i. More attention at the beginning and clearer definitions of the meaning of need and specification would have saved a lot of work.

Appendix E: Needs/Conclusions Analysis

1. This document specifically lists needs in the format of an overall topic followed by more descriptions which are ranked in order of importance. (Ranking is arranged from one to three stars, three being the most important )

2. This documents has been comprised using information from a team/client interview, faculty advisors, and a team brainstorming session.

3. This document will be compared to team progress and natural Need evolution.

|Needs Analysis |Conclusion Analysis |

|The water needs to be drinkable |The water needs to be drinkable |

|*** Filters out bacteria and other pathogens |*** Filter has successfully filtered out indicator organism of E.|

|*** Kills water borne diseases |coli |

|** Filters out sand, dirt, clay, etc. |*** The filter has not been tested on organisms smaller than 1 |

|** If uses chemical to kill bacteria the chemical must be cheap |micron, and does not filter viruses |

|and readily available to the area |** Moringa seed process reduces Turbidity from over 900 NTU to |

| |less than 1 NTU in hours |

| |** No chemicals are used |

| | |

| | |

|The filter needs to be portable |The filter needs to be portable |

|*** The filter can be carried by two or tree people |*** The filter can be carried single-handedly by one person |

|** The filter is light weight |** The filter is less than 5 lbs |

|* The filter can have built in backpack straps to make it easy to|* The filter uses a 3 gallon bucket with a handle |

|carry |* The filter can be made using abundant natural resources |

|* If the filter is cheap to make then it can be positioned at | |

|many locations, and will not need to be carried | |

|* The filter can be carried by one person | |

|Needs Analysis (cont.) |Conclusion Analysis (cont.) |

| | |

|Materials |Materials |

|*** The filter is made from materials that are abundant to East |*** The filter is made from materials that are abundant to East |

|Africa |Africa |

|** The filter is made from materials that are renewable resources|** The filter is made from materials that are renewable resources|

|** The filter materials have a low initial cost |** The filter materials have no initial cost |

|* The filter materials should be durable, reliable, and sturdy |* The filter materials are not durable, reliable, and sturdy, but|

| |are easily constructed |

| | |

|Filter Assembly |Filter Assembly |

|*** The filter is made of few parts |*** The filter has no moving parts |

|*** The filter does not need special tools for maintenance |*** The filter does not need special tools for maintenance |

|** Each phase of the filter is made of separate parts that are |** The filter is made of 2 distinct parts that are set together |

|separate and therefore easy to replace |and easily taken apart |

|** The filter can be fixed in the field |** The filter can be fixed in the field |

| | |

|Water Quantity |Water Quantity |

|*** The filters must be able to be large scale enough to supply |*** The filters are smaller in scale, suitable only for personal |

|drinking water for the people of East Africa |or small family use |

|** The filter provides enough drinking water for a family |** The filter needs to be tested for flow rate v. pressure and |

|* The filter provides enough water for 30 people |wall thickness |

| |* The filter needs to be tested for Volume output against the |

|Filter Operation |average consumption for the Maasai tribe |

|*** The filter is easy to operate | |

|** The filter is self or natured powered |Filter Operation |

|** The filter has a reasonably fast flow rate |*** The filter is easy to operate |

|** The filtration process can be a two part process |** The filter is gravity powered |

| |** The filter needs testing for flow rate |

| |** The filtration process is a two part process: (1) Moringa |

| |Seed, (2) ANU Filter |

Appendix F: Team Assessment

1. Work Breakdown Structure

The major tool used for team productivity was a detailed WBS. This not only stopped too many tasks from “falling through the cracks”, but it also allowed for greater peace of mind when it came to the project, and visual balancing of responsibilities for the whole team. In this way, “high perfoming” members were not worn down in early February, but instead were able to contribute throughout the year.

2. Early Prototyping

The next lesson learned is to start the iterations of prototyping earlier and to start with each component as it is decided upon. For our project the hardest part to prototype was the microbial filter. It took the longest to set up and to get results from. It was also a component that we knew was need from the very start and had already decided which ones we were going to try early on. As soon as we did some research we should have started prototyping for it instead of waiting until we had the rest of the design. Then we could have received feedback and able to make changes accordingly.

3. Defining Clear Goals

Team Clearwater Aid found that it was very time efficient to first define the goal of our tasks before setting out to work on a task. CWA implemented this weekly at team meetings and found that the meetings were much more time efficient and purposeful. Defining the goal of a meeting or task only takes a couple minutes and provides guidance as well as ensures that everyone involved is on the same page. Setting aside time to specify a task’s goal also allowed the team to scope what was about to be accomplished and how much time should be spent. Using this method minimizes time lagging and keeps the team focused.

4. Create Efficient and Organized Research Method

The fourth lesson the team learned was the need to develop efficient and organized project learning processes. It is important on any project for the team members to understand the underlying principles required in the project. This project learning also has to be done in a timely manner to ensure early development on the project. All the team members need to understand the basics, and a process is needed to ensure all the research done individual makes it make into the minds of the rest of the group, keeping the cross-over researching.

5. Project Immersion

Project Immersion is key to understanding the scope and limits of the project. With our project, seeing what resources were available, what conditions the product was going to be subjected to would have given the team a huge head start on the project. Other information that could be gathered by visiting and seeing the project target area would eliminate research time and correspondence time waiting for answers to simple questions. If this option is not available, contacting people or groups that are already working on similar projects can provide valuable information.

Sam Creason

1. Spend more time creating “buy-in”. This is easy to say, but it would be important to create a list of goals for each major action, and a person responsible for keeping accountability. That way the team is making their own mini-specs/needs document for each action.

2. In addition to the WBS above, it would be neat if the Project Manager had constant access to an internet posted WBS. This way, each member could go on and print out an updated WBS at any time. It would also give added accountability to perform the tasks given on time. I think that a website that is set up sooner, so that it is interactive for the team (easy download of documents, etc.) would push team productivity.

3. Develop clear roles. Each role needs a set of responsibilities. The project manager is expected to continually update the WBS. The rest of the team would then “volunteer” for the tasks that were in their “job description” (ie Client Contact, Microbial Researcher, etc)

4. Prototype earlier. It is important to get “hands on” early to help with design generation. This also gives some understanding to “how things work”

5. Have good log books. It would be a wise investment to have the team buy nice, structured books that allow them to spend less time preparing their log books and more time just doing real-time entries. Also, some continuity amongst log books would allow for easier information transfer.

Nate Cropper:

1. Documenting research in a way that is easy accessible and referenced would help immensely. The team spent two weeks at the beginning of the project just learning about what is currently being done and what wont work. A lot of this information was cited, but looking through a 4 inch thick notebook for the one page of useful information was not appealing.

2. I think one of the most useful processes the team did was making multiple prototypes. Many of the pump prototypes, for example, didn’t work revealing a pertinent aspect of the design that could be implemented on the second iteration. Information about the prototypes also needs to be documented in a manner as listed in the first lesson to validate the design process.

3. Involving people with all sorts of knowledge bases opens doors and reveals new options. Over the course of the project I had dozens of conversations with people who had absolutely no experience to large experience in the area of our project. If you are willing to explain, share and listen, often times design inspiration, improvements and alternatives can be suggested. There is a world full of knowledge, and the 6 people directly related to the project don’t know even a 1/8th of the knowledge available.

4. I learned that if people treat others as peers and do so professionally a lot more can be accomplished. This idea can and should be applied to the team dynamics, but also with people outside of the team. In other words, if faculty, professors, mentors, and professionals treat students as peers, learning is promoted as well as a professional atmosphere. I think if this idea were carried through out all areas of academia and the professional world, conflict and personal hang-ups would be reduced.

5. As a team manager, it is important to find where each person’s interests and skills are, and assign them tasks that allow those skills to be exercised. If the person likes what he or she is doing, they are much more likely to excel, to be creative and to be productive. As a team, you want to utilize the skills available for the benefit of the team and the client.

Cami Johnson:

1. My first lesson I learned was how to be an effective project manager, using the work breakdown structure as a tool. I learned what an effective project manager does, how to make sure the project progresses as scheduled, and how to work with the rest of the team as a project manager. Throughout the year, I have been able to improve my skills as manager, as well as planning and layout out a large senior project.

2. The second lesson I learned was the overall design process, and how to accomplish a project through the different phases. Understanding this process allowed me to visualize each of the smaller steps to reach the larger one, and it helped in planning out the year, making sure we had a product for our client. I learned the essential elements at different stages of a large design product, which will help me in any further projects, large or small.

3. The third lesson I learned was to begin prototyping earlier. A basic knowledge is required before the initial prototyping, but prototyping helps one gain a better understanding of how something works, especially if I do not have much experience in the area.

4. The fourth lesson I learned was how to use the WBS to achieve tasks. The WBS let me visualize what all needed to be done before a certain time, where each of the things needed to be delivered to, and what everyone else was doing. Working on a project in a team requires understanding what everyone is doing, especially when my tasks rely on completed tasks and deliverables from someone else. This tool helps break the large task into numerous smaller tasks, making it appear less intimidating.

5. The fifth lesson I learned was achieving efficient team work of an interdisciplinary team, as well as the communication barriers and other obstacles that prevent a team from achieving its full potential. This experience and knowledge will help me in further projects on how to become part of a new group and what is required and missing to work efficiently as a team.

Jenn Miller:

1. Set aside time for assessment at relatively infrequent intervals— The team should perform assessment about every one to two months. This allows time for members to improve and also ensures that the assessment will be taken seriously. If assessment is too frequent (weekly), then the team tends to disregard it; however, assessment time should be set so that it is performed and not a spontaneous reaction.

2. Prototyping should be done simultaneously with background research—In order to fully understand what the team is researching the team should do quick prototypes to test the theories that are being presented. This prototyping should be specific and quickly done (maybe an hour). I felt that the team did not fully absorb the research that was done until we did a hands on example.

3. Don’t get bogged down by frivolous documentation—When documenting work it was important to take short cuts. What was being documented needed to be explained fully, but for example, if one was doing a write up on a prototyping session a simple one page description sufficed. Throughout the year I learned that while meeting with others it is always important to write down action items that I or the team members were accountable for. Overall, I found that logbook documentation became innate because I tailored its use to fit my lifestyle.

4. Goal oriented tasks— Once the team implemented defined goals for each of our tasks, we saved a lot of time. We were able to outline a specific task, what we aimed to accomplish, and how long we were going to spend. This kept our work purposeful and time efficient, without a lot of distractions.

5. Using the WBS— The team found it very useful to use the WBS to keep track of tasks and to keep member’s accountable in a non-accusational manner. This document drove team meetings and kept work loads relatively static throughout the semester.

Michelle Lebaron:

1. The first lesson learned on this project was to be organized and set small goals for yourself. I project can seem overwhelming at first but when broken down into small pieces and each of those laid out in a timely matter until completion you the project feels obtainable. The WBS really helped out with that. I could actually see myself getting things done that I could check off a list and it made the ultimate goal seem within reach.

2. The next lesson learned was how to research as a team. To research yourself, you find the information, read about it and narrow your research based on your previous research. For a team you research then you have to present your research to your team and justify why you went the way you did with your research. You also have to write summaries of the research and where you got it so the team can refer to it. It actually helps you to organize and think about the research as well and has influenced how I will even make my personal research more effective by doing it in the same manner.

3. The next lesson learned as that it is harder to work on a multidisciplinary team. That was forewarned but I didn’t realize it would make a difference on our team as we were all still engineers within the same college. There was a line between the two sides however as we did our project. Each side had been taught in a different way and had very different expertise. It was hard to inter mingle to two different ways of thinking. I will be prepared for this on my future projects now and try and not take the knowledge as knowledge everybody has and vice versa.

4. The next lesson learned is to start the iterations of prototyping earlier and to start with each component as it is decided upon. For our project the hardest part to prototype was the microbial filter. It took the longest to set up and to get results from. It was also a component that we knew was need from the very start and had already decided which ones we were going to try early on. As soon as we did some research we should have started prototyping for it instead of waiting until we had the rest of the design. Then we could have received feedback and able to make changes accordingly.

5. The last lesson learned was that there are many different ways to design a system. Some my be better than others but as long as they work at some point you just have to say I am going this way and move forward. You cannot spend all your time trying to find a better way or you will never move forward on your design. Pick a system, design it, test it, and make changes accordingly. You are never going to have the system right or even close the first time and there will always be more than one way to design a system effectively.

Appendix G: New Testing

Microbial Test #5

Performed on 4/25/06

Goal:

To test four filters for there effectiveness in removing E.coli.

2 – 75/25 ANU filters

2 – 66/22 ANU filters

Procedure:

Pour 250ml of E.coli water at a concentration of 10^6 organisms per ml. into each apparatus and let filter.

Collect filtrate and put 5ml in 10ml of an LB broth.

Incubate for 24 hours @ 37oC

Check for growth/ no growth of E. coli

*Vaseline seal and a gravity feed was used for all tests*

Observations/ Results:

66/33 -1

Few small cracks on top but they don’t appear to go all the way through.

Only able to pour 200ml of E. coli mix into apparatus.

Diameter was about 0.75 inches for mixture to filter through.

Some Vaseline got on outlet of filter and could slow flow rate.

Flow rate was very slow, only 40ml overnight or about 12 hours

Result: Negative for E. coli

66/33 -2

Few small cracks on top but they don’t appear to go all the way through.

Diameter was about 1 inch for mixture to filter through.

Flow rate was slow at about 1 drop per 2 minutes.

Result: Positive for E. coli

75/25 -1

Some cracks on top

Only able to pour 200ml of E. coli mix into apparatus.

Diameter was about 1 inch for mixture to filter through.

Flow rate was decent at about 100ml/ 30min

Result: Positive for E. coli

75/25 -2

Large cracks on top but no cracks on bottom

Diameter was about 1 inch for mixture to filter through.

Flow rate was very slow at about 50ml/12hours

Result: Positive for E. coli

Conclusions:

Based on Dr. Minnich’s best guess the E.coli is still getting through the 66/33 filters at about 10 organisms per liter. The filters are probably not consistent enough in there pour spaces and may have too many cracks in them. The 75/25 filters are probably having the same problems. The flow rate for any working filter is still too small to be practical and need a pressurized design.

-----------------------

Filter Material

Coffee Grounds / Tea

Free

5 Gal Bucket

$2.50

Clay

$1.00

Moringa Seeds

$1.00

Manufacturing Materials

Wood/ Manure

N/A

Water

N/A

Bowl

N/A

Plastic Grocerie Bag

N/A

Matches/ Lighter

N/A

Total

$4.50

Funnel—Entrance to turbidity filter

PVC piping with holes, covered by polar fleece turbidity filter.

Check valve 1—Turbidity filtered water enters into piping system

Grounds & clay.

Check valve 2—water pushed through piping into microbial filter.

Clean drinking water exit

Hand-pump—pushes water through ceramic filter

Leather disk—seals PVC casing

PVC casing, connections, and tubing.

Ceramic filter casing with O-rings for sealant

Water enters from Moringa seed settled water

All thread rod, washers, and nuts

Filter Material

Coffee Grounds / Tea

Free

5 Gal Bucket

$2.50

Clay

$1.00

Moringa Seeds

$1.00

Manufacturing Materials

Wood/ Manure

N/A

Water

N/A

Bowl

N/A

Plastic Grocerie Bag

N/A

Matches/ Lighter

N/A

Total

$4.50

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