Clean Water for Everyone

Biofilter Project

Presented on November 14, 2005

Problem Definition:

How can we provide clean water for the people of East Africa?

The real goal is clean water.

Ideally, this will be by designing a portable biofilter.

Research Topics:

Culture

Pathogens

Turbidity

Purification

Large and Small Particle Filtration

1.  The filter must produce safe drinking water 100% of the time.

2.  A simple water quality test must be available to establish the safety of the water output.

3.  Components of the filter must be accessible to rural areas (either present or available in the closest urban area).

4.  The filter must be able to function with manual power only.  Auxiliary power, if available, could be substituted for or augment manual power. 

Needs:

Wants• The components of the filter should be transportable

by human power or animal power to areas not accessible to vehicles.

• The filter should be as simple to assemble, operate and maintain as possible.

• The filter should be scalable to adjust to the amount of water and materials available.

• Deployment plans for filter implementation must consider the culture and technical sophistication of the people who will be using it.

Specifications

Clean Water:• The water should be less than 5 NTU and filtered to a

point .2 micronsSource: World Health Organization

Portability:• The people themselves could carry the filter, whether it is

one unit or is easily broken down, and put back together.

Deliverables and ConstraintsDeliverables:

A filter which meets the needs of the project.

Constraints:SimpleEconomicalUses native materialsReliableSAFE

Potential Filters Mediums:

1. Sand

2. Ceramic

3. Charcoal

4. ANU Coffee/Clay

5. Fabric

6. Many more…

BenefitsPortableEasily Renewable FiltersSpeedy FiltrationInexpensive

RisksMoving PartsInstruction Needed for ConstructionNot Tested

CONCEPT 1: LEVER PUMP FILTER

ProcessDirty water enters upper reservoirUpstroke on lever arm opens inlet valve,

dirty water enters pressure chamberDown stroke of lever arm closes inlet

valve, presses water through multistage filtration

Clean water enters clean water reservoir and stored

Repeat process as many times as needed

Water squirt indicator notifies user of filter exhaustion

CONCEPT 2: SLOW SAND FILTER

BenefitsInexpensiveTested and ProvenSimple ConstructionLarge Volumes of Water

RisksStationaryEducation for Use and MaintenanceBiological Layer Growth

ProcessWater enters the pre filter for large particle

filtration and turbidity filtration.Water enters the slow sand filter.Bacteria and remaining particles filtered with

the Schmutzdecke and multiple layers of sand

Clean drinking water exits.After time, Schmutzdecke needs to be

removed and grown again. Takes about a week with proper care.

SAND

WATER

GRAVEL

CONCEPT 3: SLOW SAND FILTER

BenefitsEasily Replaceable FiltersSpeedy FiltrationPortable

RisksComplicated DesignIntensive ConstructionNot Tested

Process1. Dirty water poured into

pump housing through spout

2. Turing hand crack presses water through the filter layers

3. Clean water stored in the bottom of the filter

4. Repeat as many times as needed

5. Water squirt indicator notifies user of filter exhaustion

Recommendation:

Slow Sand Lever Arm Press Pump

Risk Solutions 4 2.5 2

Portability 1 4 3

Safety* 4 3* 3

Cost 3 3 1

Feasibility 3 3 1

Design Matrix:

Total: 15 15.5 10

The team is committed to designing a better method of providing East Africa with clean water. We believe that with further research, and time the Lever Arm Design can do that while still being portable. However, permanent slow sand filters are proven, reliable, and can be improved upon.

Foreseeable Threats:1. Can we reliably detect and identify pathogens?

2. Will the coffee/clay filter work?

3. Will the filters used, meet those specifications expected?

Outlined Schedule:

•December: System Integration (Phase 3)

•January: Detail Design (Phase 4)

•February - March: Fabrication (Phase 5)

•March - April: Validation (Phase 6)

•End of April - Beginning of May: Delivery

Webpage:

http://seniordesign.engr.uidaho.edu/2005_2006/clearwater

Questions?

For more information, check outhttp://seniordesign.engr.uidaho.edu/2005_2006/clearwater/index.html

Or contact the teamBiofilter@uidaho.edu