High Temperature Waste Pasteurizer

Brian KilgerKyle Cohn

Kyle WestonStephanie Mauro

P13411

The Team

Kyle Weston- Team Leader

Stephanie Mauro- Thermal Engineer

Kyle Cohn- Alternative Energy Engineer

Brian Kilger- Materials Engineer

Agenda

• Feedback (expectations and priorities for review)• Review from systems design review• Solar cooker experiment• The selected design and key features• Construction plan• Thermal analysis of the design• Updated risk assessment and project plan going

into MSDII

Feedback We are Looking for from This Review

• Comments on selected design and material selection

• Pros and cons of the proposed test plan

• Compatibility of our ideas with Haiti

Problem Statement

• The primary objective of this project is to transform human waste into a safe to use fertilizer using renewable energy. The waste pasteurizer will be designed to meet the needs of a Haitian family (3-5 liters) while keeping the cost per unit under $50 USD.

Customer Needs

Engineering Specifications

Functional Decomposition

Systems Architecture

The Simplified Project Scope

Remaining Schedule Task List

The Solar Cooker Experiments• 3 separate experiments– Trial 1:

• No Adjustments• Small Stainless Steel Pot• Not Peak Sunlight

– Trial 2: • Adjustments• Small Stainless Steel Pot• Not Peak Sunlight

– Trial 3: • Adjustments• Large Pot• Peak Sunlight

The Summarized Results

0 50 100 150 200 25040

60

80

100

120

140

160

180

Temperature of Water

Experiment 1 Water TempExperiment 2 Water TempExperiment 3 Water Temp

Time (Min)

Degr

ees (

F)

0 50 100 150 200 25040

90

140

190

240

290

Temperature of Box

Experiment 1 Box TempExperiment 2 Box TempExperiment 3 Box Temp

Time (Min)

Degr

ees (

F)

The Summarized ResultsExperiment 1

Time Elapsed 150mMax Temperature of Box 162FMax Temperature of Water 90FMinutes to 149F requirement NA

Experiment 2Time Elapsed 180mMax Temperature of Box 238FMax Temperature of Water 144FMinutes to 149F requirement NA

Experiment 3Time Elapsed 240Max Temperature of Box 232Max Temperature of Water 170Minutes to 149F requirement ~150m

The Selected Design• Cylindrical container for

waste handling inside another cylindrical container, using air as insulation

• Heated from direct sunlight to top and reflected light from side flaps

• Removable lid and inner container

• Temperature indicator tool sticking through the lid

The Selected Design

• Cross-Sectional View • Fully Assembled Unit

Test Plan

Bill of Materials

What is a WAPI

• Sight dependent• All parts submerged

in water• Need to take out and

flip over

The Modified WAPI Idea(iPooP)

• Touch dependent• No touching parts submerged in

waste• Spring loaded so wax won’t stick

Sealing MechanismLid design for use with latch• Grooves cut into tab of same

material as lid (acrylic) for latch to grab.

Possible Latches• Attach larger part to side of

outer bucket• Pull either from grooved tab

attached to lid or screw loop into side of lid and pull down from there.

Feasibility

• Solar irradiance data was collected from Puerto Rico using the average conditions by day for the past 40 years

• Determined how many days the minimum wattage was met for 5 hours

• Calculations show that 306 days will meet our needs

Material Properties for Thermal AnalysisComposition of Human Waste in Developing countries

Component % Sub-components % Thermal Conductivity [W/mK]

Effective Thermal Conductivity ofWaste [W/mK]

Water 0.9 none none 0.563

2.5269652Dry Composition 0.1

Organic Matter 0.256 0.15Nitrogen 0.07 0.234

Phosphorus (P2O5) 0.054 0.118Potassium (K2O) 0.025 85

Carbon 0.55 21Calcium (CaO) 0.045 143.7

Summary of Materials Used

Component MaterialThermal

Conductivity [W/mK]

Plastic Bucket Polyethelene 0.42Graniteware Pot Steel, Porcelain 8.75

Lid Acrylic 0.2Insulation Air 0.027

Input Waste 2.527Stand/Support Concrete 0.1

• Composition of Waste gathered from Appropriate Technology for Water Supply and Sanitation composed by World Bank in December 1980.

Steady State Thermal Analysis• Components of Analysis

– Outer bucket– Inner bucket– Air as insulation– Waste– Acrylic Lid

• Thermal Loads Applied– Insulated at axis of symmetry– Convection along outer

bucket side and bottom– Energy Applied to top surface

of lid in W

Waste

Air

Air

Lid

Axis of symmetry

Inner bucket

Outer bucket

Results of Thermal Analysis

Waste between 62.35 and 71.17 °C

50W applied to top of lid: 60W applied to top of lid:

Waste between 69.42and 80.01 °C

Results of Thermal Analysis Continued

Waste between 60.55 and 71.64°C

75W applied to top of lid: • Using Concrete as

support/stand for inner bucket.– Requires a significant

amount more of energy to heat the waste to the desired temperature.

– Using kconcrete=0.1 W/mK

Updated Risk Assessment

Updated Risk Assessment

Updated Risk Assessment

Updated Risk Assessment

Updated Risk Assessment

MSD II First Steps

• Address any outstanding items from the Project Review

• Develop a project plan for MSD II• Purchase necessary materials• Initiate contact with those in charge of

testing equipment• Begin assembly

Any Additional Questions?

Thank You All for Your Time and Feedback