MATERNAL AND CHILD HEALTH CLINICLAS MERCEDES, HONDURASPreliminary Design (30%)January 27, 2009Janelle Barth, Stephanie Chang, Walter Li, Greer Mackebee

road: church side

field side

STRUCTURAL DESIGN

Weighting Criteria

Constructability: Is it easy to build? Will we need more materials? Bricks, wood, or tin? Is it easy to access/install the solar panel?

Access to water source: How much piping (and labor) will be needed to obtain fresh water

Access to sewage disposal: How much piping (and labor) will be needed to dispose of sewage properly? Will it even be possible to dispose of it properly from location of kitchen?

Ventilation: Can air flow easily in AND out of the building? Are there obstructions?

Concrete Masonry Units (CMUs) in the Las Mercedes Primary school

Adobe bricks

Structural Design Decision Matrix0.2 0.3 0.35 0.15 1

Option ConstructabilityAccess to

water source

Access to sewage disposal

Ventilation Weighted Total

1) kitchen on side,

gable7 8 8 5 7.35

2) kitchen in back,

gable7 10 5 10 7.65

3) kitchen on side, single pitch

9 8 8 5 7.75

4) kitchen in back, single pitch

9 10 5 10 8.05

Decisions Made So Far

Optimal location: lowest area on site slope change is minimal needs for clinic limit our choices of location (because

of size) Optimal size, dimensions: 30’x70’

fits necessary lodging, kitchen, medical needs rectangle allows for more sunlight, ventilation fits topographical lines more appropriately

Farmer’s crops right next to clinic site

Next Steps

Ventilation system to prevent spread of airborne disease: Wind tunnel? Fans in windows Screen in windows

Next Steps

Internal structure (layout of rooms) Preferably at least one large room for serving as a

community meeting-place or treating large groups of people

Bedroom for full-year nurse staffer Office with laptops for keeping records, refrigerator for

short-term storage of vaccines/medications Smaller exam rooms (1-2?) for private treatment or

curtain/other dividers for the large room Dormitory for volunteers (8 bunk beds?) Waiting room (?) Simple “kitchen” with smoke-diverting wood-burning stove

(?)

WATER SYSTEMS

Water from stream (in the

tank)

Water from stream (in the

tank)Physical FilterPhysical Filter Disinfection /

TreatmentDisinfection /

Treatment

Back into the EnvironmentBack into the Environment

Waste Removal System

Waste Removal System

Clinic UseClinic Use

Water Path

Latrine WasteLatrine Waste

Graywater

Blackwater

Two Areas of Interest

1. Water Purification Needs to be effective

Filter particles Treat water for diseases

Should be low cost Should be possible to construct with locally available materials Needs to be easy to maintain

2. Waste Management Must effectively contain harmful materials Should be low maintenance Cannot require any unavailable technologies Soil permeability can be found through percolation

Water Purification System

Ultraviolet Disinfection

Equipment: UV bulb, quartz sleeve Effectiveness: 1-log reduction of Giardia, 4-log

reduction of viruses, effective for Cryptosporidium Cost: US$ 80-300 Lifetime: bulb lasts 10 to 12 months Maintenance: replace bulbs; check quartz sleeve

every 6 months; monitor for scaling and overall effectiveness

Ultraviolet Disinfection

Pros: Capable of disinfecting

water faster than chlorine No cumbersome retention

tanks or potentially harmful materials

Cost effective No residual effect (change

in water taste, odor, pH, or conductivity)

“Operator friendly”

Cons: Doesn’t remove dissolved organics,

inorganic compounds, or particles in the water

Needs electricity Bulb needs to be replaced every 10-

12 months; old bulbs need proper disposal

Replacement of parts Bulbs – every 10-12 months (need

proper disposal) Ballast – 10 years Quartz sleeve – 5 years

More difficult equipment repair and regular cleaning required

UV Disinfection

Factors that reduce UV disinfection effectiveness include: Iron manganese Total dissolved solids (TDS) Turbidity (inability of light to travel through water) Suspended solids

May need to be used in conjunction with another filtration system (possibly a membrane or sand-gravel system)

Chlorine

Pros: Can be cheap (only need

tablets, pump, tank for water storage, filter)

Very effective at fighting E. coli

Somewhat easy to maintain

Electricity not necessarily required

Upstream treatment possible for school and Regino’s house because of residual

Cons: Chemical dosing hard to

regulate Possible to overdose the

water Would require another

type of purification to remove excess chlorine

Pressures must be dealt with (might require a separate pump system)

Unreliable in fighting Giardia

Undesirable taste Requires purchase of

chlorine

Evaluation of Treatment Options

0.4 0.1 0.3 0.2 1

Technology Effectiveness Low CostEase of Maint.

Locally Avail.   Weighted Total

UV disinfection 10 2 7 1 6.5

Chlorination 8 5 5 2 5.6

Waste System

Percolation

Percolation

Septic Tank / Aqua Privy

Pros: Most efficient Water tight Very sanitary if

functioning properly

Cons: Sludge from tank must

be emptied mechanically every 1 to 5 years

Needs lots of area to function

Uses a high volume of water per flush

Regular maintenance unavailable

Offset Single Pit Toilet Pros:

Versatile Inexpensive to construct and

maintain (only has to be cleaned daily with some water and disinfectant)

Sludge can be used as fertilizer after being buried

Cons: If not cleaned properly, risk

of disease and groundwater contamination

Must be reconstructed annually in a different location

Possible for the pipe (U-trap) to become blocked, rendering the whole system unusable

Toilet paper and other bulky materials cannot be used

Must be 6 meters away from building; cannot be indoor

Offset Double Pit Toilet

Pros: Very versatile Safer pit sludge Inexpensive (US$ 75-

212) Sludge can be used as a

fertilizer No need for yearly

reconstruction (while one pit is full and decomposing, the other pit is in use)

Water Seal

Cons: Similar to those for

single pit

Offset Double Pit Toilet

Compost Latrine

Pros: Produces fertilizer Vaults don’t have to

be moved (like in the Offset Double Pit Latrine)

Capable of decomposing most household waste, also

Easy to install

Cons: More expensive than

Pour-Flush systems Grass, weeds, or

sawdust must be added daily to reduce odor

Must be dosed with disinfectant daily

Floor must be scrubbed daily

Simple Pit Latrine

Pros: Very cheap Very easy to build

Cons: Not sustainable (must

be moved to a new site after a year)

Bad odor Uncomfortable No seal

Evaluation of Waste Disposal Options

0.15 0.05 0.25 0.09 0.23 0.23 1

Technology Effectiveness Low Cost Ease of Maint. Locally Avail. Installation Sustainability Weighted Total

Septic System 9 3 2 7 4 8 5.39

Compost Latrine 6 6 4 10 9 6 6.55

Aqua Privy 8 3 2 7 5 8 5.47

Offset Double Pit Toilet 8 8 6 10 8 6 7.22

Offset Single Pit Toilet 6 9 5 10 9 5 6.72

Simple Pit Latrine 5 9 5 10 9 2 5.88

Moving Forward: Concerns

Location? The waste removal system needs enough water to keep

“things” moving Proximity to agriculture / water Amount of power necessary for the UV filtration system Reasons for pit latrine failure:

Soil incapable of absorbing water High water table Pit collapse No water available Housing structure damaged Improper maintenance

PHOTOVOLTAIC ENERGY SYSTEM

Determining System Capacity

Depends on appliance load Known appliances

Electric lighting 2-3 laptops Refrigerator (?) for vaccines, medicines Electric fan (?) Possibly UV water purification system

Be prepared for extra appliances (medical equipment?)

Appliance Evaluation Criteria

Cost – how expensive? Performance – can it reliably maintain a proper

temperature for vaccine/medication/diagnostic sample storage?

Power consumption – how much power does it draw?

Availability – can we get how much will it from in-country or regionally at about the same cost?

Durability – how long will it last? (may not be an important criterion)

Cost Performance Power consumption Weighted Total

Refrigeration 0.2 0.3 0.5 1

Electrolux 50 DC fridge5 6 2 3.8

BP Solar VR 50 (38liters/5 liters)

2 9 6 6.1

SunFrost 51/343 8 8 7

SunDanzer 51 liters9 3 9 7.2

GE Small Fridge 48liters10 3 3 4.4

Computer0.2 ? 0.8 1

Inveneo5 ? 7 6.6

Netbook9 ? 10 9.8

Next Steps

Rate appliances on other criteria; reevaluate decisions

Add other appliance types Lighting UV purification Fan

Next Steps

1. Confirming necessary/desired appliances with Dr. Clements (by 2/3)

2. Calculate system component specifications (by 2/10) Crystalline silicon PV panels (cheapest, but not necessarily most

efficient) Charge controller Deep-cycle battery Inverter (conversion from DC to AC for laptops) Check calculations with Dr. Paul Klenk of the ECE department

3. Preliminary mounting design (by 2/17)4. Identify parts and suppliers (by 2/24)

Work out transportation/shipping logistics (by 3/10)5. Estimate costs (by 2/24)6. Final system design and possible prototype/testing (by 3/31)