26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECT

Integrating Composting Toilets withinthe Concept of an Eco-Beach

Richard Forbes - PhysicsGemma Gotch - ChemistryPanagiotis Grigorakis – Electrical EngineeringJudith Martyns-Yellowe – Environmental Engineering

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTOverview

• Background• Eco-Beach Concept• Project Objectives• Beach Classification• Feasibility of Wind & Solar• Composting Theory• ESP-r Model & Results• Composting Toilet Design• Environmental & Economic Impact• Conclusion

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECT

• Waste on Beach - Mainly landfilled by local

authorities

- Estimated £585,000 spent

on beach cleaning in 2006

• Facilities- Few toilets and kiosks

(centralized)

- Restricted locations

Background

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTEco-Beach Concept

A framework that delivers a comprehensive approach to sustainable beach management

Key:

= Education

= Kiosk

= Composting Toilet

= Recycling Point

= Transport

= Access Route

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTProject Objectives

• Define Eco-Beach Concept

• Develop a beach classification guide

• Feasibility Study of Wind & Solar Energy

• Design a composting toilet

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTBeach Classification

Guideline for determining requirements of an

Eco-Beach.

Category 1

Category 2

Category 3

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTBeach Classification 2

Category 1: Remote Beach, South Harris

Best Environmental option to leave beaches as they are.

Category 2: Ayr Beach

Composting Toilet, Recycling facilities, Access for disabled use, Educational notices.

Category 3: St Andrew’s (West Sands)

Composting Toilets, Recycling facilities, public transport service, Educational activities on the beach, sustainable kiosk possibility.

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTWind and Solar Power

• Wind

• PV– Good match with demand– Low intensity (and structures are small)

• Solar Water Heating– Good match with demand

Velocity Exceedence Curve for Irvine

0

2

4

6

8

10

0 50 100 150 200

time / days

velo

city

/ m

s-1

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTWind and Solar

• Structures requiring power: Kiosk, Ice Cream Van, Toilet

ApplicationElectrical Appliance

Rating

Renewable Supply Option

Area required

(m2)

Cost (£’000s)

Cooking 3 kW Biofuel N/A

Hot Water 1 kWSolar

Collector0.5

Ice Cream Maker

800 W PV 8.4 6

Cold Storage

100 W PV 1.4 1

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTSupplying Cold Storage

Fridge & Freezer Profile

0

50

100

150

200

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Time (Hr)

Po

wer

Co

nsu

mp

tio

n (

W)

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTComposting Toilet

• Composting Process:

• Heat produced can result in T ~ 70oC• Composting toilets don’t achieve this

Composting Pile

Micro Organisms

Finished Product

O2

Heat

CO2H2O

Human Waste

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTComposting Toilets

• Can high temperatures be achieved?– Insulation– Optimal conditions (moisture, C:N ratio, air flow)

• Insulation requirements determined by dynamic modelling and experiments

• Conditions controlled by features of overall design

• Calorific Value ~ 25 MJ / kg

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECT

01020

3040

07:1

2

09:3

6

12:0

0

14:2

4

16:4

8

19:1

2

21:3

6

Time

Tem

p /

oC

Composting

• Peak heating power ~ 84 W / kg

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTESP-r Model

• Objective

• Construction

• 250W Gain – 3kg of faeces

• Airflow – 36 m3/hr

• Control – 55-70 °C

• Insulation

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTESP-r Results

• Mean temperature is 62 °C• Insulation → 10cm polystyrene

Compost temperature

Mean temperature

Ambient Temperature

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTComposting Toilet Design

Key considerations in our design• Maintaining optimum conditions for a thermophillic process• Low energy toilet• Ease of maintenance• Multifunctional• A finished product that is safe to handle

Achieving optimum conditions• Moisture control – Diverting and composting urine• Aeration – Ventilation and Exhaust powered by 10W PV panel• C:N ratio – Saw dust provides the carbon required to maintain

a C:N ratio of 30:1• Temperature – Insulating chamber with 10cm polystyrene

boards• Design of a saw dust dispenser

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECT

0.40

0.30 Sawdust flusher

All dimensions in meters

2.80

0.10

2.00

0.50

1.80

1.00

0.05 1.7

0

2.00

1.3

0 1.0

0

Dry urinals

Urine composter

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTBenefits of the Eco-beach Concept

Environment• Reduced energy consumption

• Pollution and nutrification reduction

• Re-use of waste, less use of landfills

• Improved environmental & sustainability awareness

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTBenefits (II)

Socio-Economic• Enhanced tourism

• More revenue for councils• Improved accessibility• Alternative uses for beach litter – waste becomes a

resource• Cost of land filling waste is reduced considerably

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTLimitations & Recommendations

• Lack of accurate data from local councils• Experimental conditions

• Design of an Eco centre for educational activities, café, shops which would be powered entirely by renewable supply

• Comprehensive cost study of waste management on the beach

• Consider other applications for the toilet

such as festivals, construction sites• Sophisticated control system

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECTConclusions

• Defined the concept of the Eco beach• Beach classification model• Solar resource most suited for the beach -

there are limitations• High temperature composting is possible

without heaters• Toilet design

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECT

Thank you for listening…………

Any Questions?

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECT

Food

Human Waste

Toilet

Compost

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECT

Drinking WaterFresh Water

Energy, Chemicals

Foul Water

Human Waste

Food

Energy

Contaminated Water

Water for discharge to sea

Sludge

Anaerobic Digestion

Aerobic Digestion

Compost

26th April 2007

ECO-BEACH PROJECTECO-BEACH PROJECT