1. “UV Tube” Water Disinfection P07402
Sponsored by
Dr. Andres Carrano and Dr. Brian Thorn of the KGCOE ISE Department
Final Project Review • 18 May 2007

2. P07402: UV Water Disinfection Project
Anna Murray Project Management (ME)
Miguel Bazan Design for Manufacture (ISE)
Micah Brewer Material Selection, CAD (ME)
Manaal Eisa Life Cycle Assessment (ISE)
Gregory Hupp Product Testing, CAD (ME)
Robert Norquest Fluids Analysis (ME)
Brendan Richard Electrical Design (EE)
KGCOE Multidisciplinary Sr. Design

3. KGCOE Multidisciplinary Sr. Design
Outline
Project Background
Needs assessment & specifications
Concept Generation and Selection
Final Design
Testing Results
Summary of Design Improvements
Next Phase Considerations
KGCOE Multidisciplinary Sr. Design

4. KGCOE Multidisciplinary Sr. Design
Project Motivation
1 in 6 people in the world lack access to “improved” drinking water source
Water borne illness claims the lives of 1.7 million people annually (World Health Organization)
Photos courtesy of Sarah Brownell
KGCOE Multidisciplinary Sr. Design

5. KGCOE Multidisciplinary Sr. Design
UV Disinfection
Function of light Intensity and tube residence time
KGCOE Multidisciplinary Sr. Design

6. KGCOE Multidisciplinary Sr. Design
Project Description
Point-of use device used to disinfect water using exposure to UV radiation
Target user: residents rural areas of developing countries (Venezuela)
Building upon a current design
KGCOE Multidisciplinary Sr. Design
Photo courtesy of Sarah Brownell

7. Issues of Current Design
Accessibility of bulb for repair
Difficult to manufacture
Rolling/drilling stainless steel
Leakage
Water turbidity
No safety design
KGCOE Multidisciplinary Sr. Design

8. KGCOE Multidisciplinary Sr. Design
Customer Needs
Tier I
Tier II
Tier III
Easy to build, install and use. User should know when the device is on.
Easy to take apart, clean, and repair.
Safe from electric shock and UV exposure. Effective at sterilization and child proof.
Inexpensive to build and maintain.
Utilizes power grid, alternative power source available.
Adaptable fluid input.
Reliable. Doesn’t leak or clog.
Lasts and is sturdy.
Build & repair with local materials.
Environmentally benign.
Power efficient, works quickly.
Small and lightweight.
Looks good.
Water output is clear, odor-free, good taste.
Multilingual operations and maintenance manual provided with universal symbols.
KGCOE Multidisciplinary Sr. Design

9. KGCOE Multidisciplinary Sr. Design
Specifications
Metric
Units
Marginal Value
Ideal Value
Number of installation steps
Number 50 30
Usability test-Ease of use %
90%
95%
Number of total parts 20
Water flow rate
L/Min 3 6
Filter output Size
Microns 10 5
Filter turbidity output
FTU
Usability test- construction
Time to disassemble
Minutes 1
Cost of materials
USD
100 40
Power consumed per year
KWhr
50   5
Cost to operate per year
20  2 
UV dose
J/m2
400
800
Weight Kg 7
Volume m3
0.1
0.075
Max footprint m2
0.3
User is not exposed to UV radiation
Binary
Yes
Enclosure of core components (ballast, bulb)
Device indicates On/Off
Table 2: Target Specifications
KGCOE Multidisciplinary Sr. Design

10. Functional Diagram Grid (AC) Power UV Bulb Energy Alternative
Disinfect water
Disinfected Water
Water input sources
Water flow through cavity
Materials
Filter water
infected water
sediment
Sediment, Dirt
KGCOE Multidisciplinary Sr. Design

11. Selected Design Concept
Sand pre-filter
Stainless steel channel with removable wooden lid
Bag filter in reservoir
DC Generator to 12 volt battery
KGCOE Multidisciplinary Sr. Design

12. Design Concept: Tube Detail
KGCOE Multidisciplinary Sr. Design

13. KGCOE Multidisciplinary Sr. Design
Final Design
KGCOE Multidisciplinary Sr. Design

14. KGCOE Multidisciplinary Sr. Design
Final Design
Canvas filter
Electrical system
Bag filter
Safety switch
Outlet and Drain
Tube
UV bulb
KGCOE Multidisciplinary Sr. Design

15. Prototype Construction
KGCOE Multidisciplinary Sr. Design

16. KGCOE Multidisciplinary Sr. Design
Solar System
300 mA, 4.5 Watt panel
8 Amp-hour, 12 V Battery
KGCOE Multidisciplinary Sr. Design

17. KGCOE Multidisciplinary Sr. Design
Product Testing
Filter Testing
Flow Testing
Aluminum/UV Interaction Testing
Biological Testing
Solar System Testing
Usability
Ease of construction
Ease of use
KGCOE Multidisciplinary Sr. Design

18. Filter, Flow and Aluminum Testing Results
Filter Testing
Reduction from 300 to 2 FTU using 4 layers of canvas.
Chosen for lightweight, relative consistency and ease of use
Flow Testing
Range (based on fluence model): 3-6 L/min
Test: 2.9 – 4.1 L/min
Aluminum/UV Interaction
EPA Recommended limit: 0.05 mg/L
Test results: 3.18 mg/L
KGCOE Multidisciplinary Sr. Design

19. Minimum Theoretical Fluence Average Experiemtnal Fluence
Biological Testing
MS2 Bacteriophage
2 samples
Log reductions of 5.45 and 5.15
Corresponding UV dose of 1335 and 1265 J/m2
Minimum Theoretical Fluence
Average Experiemtnal Fluence
KGCOE Multidisciplinary Sr. Design

20. KGCOE Multidisciplinary Sr. Design
Electrical Testing
Standard Power Testing (120V AC)
Total Yearly Power Consumption: 6 KWh
Alternative Power Testing (Solar)
300 minutes to charge battery to 75%
Can run for 3 consecutive days without recharging.
KGCOE Multidisciplinary Sr. Design

21. Usability Testing: construction
Average Assembly Time:
1.6 hours for experienced
1.9 hours for inexperienced
Perceived Difficulty to Assemble:
85% thought it was of “medium” difficulty or easier
Ease of Use:
100% thought it was “easy” to “very easy” to use
KGCOE Multidisciplinary Sr. Design

22. Summary of Design Improvements
Solar Option
Ease of repair, maintenance, construction
Top-down construction, easy access to bulb.
Use of locally available materials
Standard sizes of wood, hose, etc.
Elimination of some PVC
Safety features
Switch interference
Sealing of light by wooden enclosure
Improved tube drainage between uses
Filtration system: Turbidity reduction
Cost
Materials: $ (retail)
Maintenance: ~$11
KGCOE Multidisciplinary Sr. Design

23. KGCOE Multidisciplinary Sr. Design
Future Work
Eliminate all PVC (new end cap material)
Better water and light sealing
Allow tube to drain fully
Research use of LEDs
New tube material testing: cheaper, safe w/UVC
Easier removal of top
Water input adaptability for use with pressurized systems
More affordable alternative power
Long-term field or use testing
Design for mass production: expands material, design options and will reduce number of components, dependence on fasteners and cost, as well as allowing easier assembly operations.
KGCOE Multidisciplinary Sr. Design

24. Questions?