Ecosan concept - Closing the Loop

Michael Kropac, seecon international, Switzerland

Ecosan Expert Training CourseCapacity Building for Ecological Sanitation in Bhutan

What does sanitation include?

What does sanitation include?

safe collection, storage, treatment and recycling of human excreta (faeces and urine) and sewage effluents

drainage and disposal (re-use, recycling) of household grey water

management/ recycling of (organic) solid wastes

treatment and disposal/ recycling of drainage of stormwater

collection and management of industrial waste products

management of hazardous wastes, including hospital wastes, and chemical/radioactive and other dangerous substances.Source: (3)

J.Heeb

E.Menger-Krug

M.Wafler

Ma

in F

oc

us o

f Ec

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an

Problems we currently face: No Sanitation…

Source: Joint Monitoring Programme for Water Supply and Sanitation (JMP). Progress on Drinking Water and Sanitation: Special Focus on Sanitation. UNICEF, New York and WHO, Geneva, 2008.

Sanitation Coverage Bhutan 2006

Shared; 5%

Open defecation;

12%Improved; 52%

Unimproved; 31%

Problems we currently face: Not working Sanitation…

• Users not involved in sanitation decisions

• Users do not acknowledge importance of sanitation

• Sanitation not adapted to local conditions

• No sense of ownership by the people• No or insufficient maintenance

Sanitation systems are working improperly… or not at all

Problems we currently face: Unimproved Sanitation…

• People don’t like using smelly toilets

• Toilets are not hygienic• Toilets are a health risk

Safe and healthy sanitation not ensured

Problems we currently face: (Ground)-water pollution…

On-site wastewater disposal systems like pit latrines or soak pits can contaminate groundwater (infiltration of wastewater) when the groundwater table is high

Source: (4)

Health risk: Polluted well-water

Problems we currently face: Flush Toilets waste water

*Based on the Swiss average for a toilet that uses about 8 L of Water per flush (11).

With conventional waterborne flush-toilets, we mix

roughly 50 kg of faecal matter (per person/year)

roughly 500 l of urine (per person/year)

with roughly 20’000l of clean flushwater*

50 kg

500 L

20’000 L

If this wastewater is discharged untreated into rivers, an even higher amount of water is polluted

© Arun

Problems we currently face: Conventional Waterborne Sanitation

What happens at the end of the pipe?

…are “flush and forget” sanitation solutions, where human wastes are flushed away with huge amounts of scarce freshwater, polluting rivers and the drinking water of people living further downstream.

Problems we currently face: Conventional Waterborne Sanitation

What happens at the end of the pipe?

If we are very lucky, there might be a “state of the art” conventional Sewage Treatment Plant:

Which will need:

• Long sewer network & pumps to get the wastewater to the plant

• Electricity for aeration, pumps and other moving parts

• Skilled (and thus expensive) operation & maintenance staff

• Backup generator for powercuts

• Diesel for generator

Who will pay for this?

Problems we currently face: Conventional Waterborne Sanitation

Problem is shifted downstream!

Who will pay for this?

Usually nobody!

• Wastewater is moved out of cities

• But worldwide, approx. 90% of the wastewater is not treated (properly)

• Environment & water sources further downstream are polluted

Conventional Sanitation: No Recycling of Water and Nutrients

• Nutrient recovery not done or often impossible in cities (due to the mixing of domestic wastewater with industrial wastewater)

• Huge demand for energy intensive artificial fertilisers, in response to the problem of decreasing soil fertility. (16)

Water Nutrients

?

Alternative, sustainable solutions are needed!

Sustainable sanitation solutions :

1. should be eco-friendly (no pollution of ground- and surface water)

2. need to be user-friendly

3. should need low maintenance

4. should be cost effective

5. should produce and not require energy (e.g. biogas)

6. are usually decentralized

7. should reuse nutrients, and water contained in wastewater

J. Heeb K. ConradinK. Conradin J. Heeb P. JenssenP. Jenssen K. Conradin

We need to rethink our sanitation approach; a new philosophy is needed!

Ecological Sanitation as a Sustainable Solution

NUTRIENTS NUTRIENTS

closing the loopbetween sanitation

and agriculture

FOODFOOD

Pathogen destruction

Source: (4)

The basic principle of ecological sanitation is to close the loop between sanitation and agriculture without compromising health

Ecological Sanitation as a Sustainable Solution

Ecosan is a new way of thinking

sanitation, not a specific technology!

Ecological Sanitation…•…regards all (dry and wet) “wastes” as resources …•…which can be recovered and safely reused and recycled after adequate treatment in agriculture.

Closing the Loop: Reuse of Urine and Faeces in Agriculture

Fertilizer Equivalence of Yearly per Capita Excreted Nutrients and Fertiliser Requirements for Producing

250 kg of Cereals

0

1

2

3

4

5

6

N N P P K K

Nut

rien

t (kg

)

cerealrequirements

faeces

urine

Source: (33)

N = Nitrogen

P = Phosphorus

K = Potassium Urine only

faeces & urine

none

source: Vinnerås, 2003

Closing the Loop: Urine as Fertilizer

Urine is an excellent nitrogen-rich fertilizer!

Sugar cane without urine Sugar cane with urine

Closing the Loop: Faeces as Compost

Treated faeces give excellent compost that improve the soil

source: Petter Jenssen

untreated soil

compost improved soil

After one week without water... Benefits of Compost:

Improves soil structure

Improves pore space

Increases water-holding

Better water supply for crops

Better storage and exchange capacity for (micro) nutrients

Reservoir of N P K S steadily released by mineralisation

etc.

!Attention!: There are many disease-causing pathogens in faeces proper treatment is necessary!

Closing the Loop: Other Reuse Possibilities

Biogas as a sustainable energy source from wastewater:

For cooking For heating For lights For electricity production

Reuse of water after treatment: Irrigation in agriculture Industry, flush for toilets Recharge of groundwater

Other Reuse Possibilities:

Advantages of ecosan Systems: Closing the Loop(s)

Watering garden

Recrea-tional water

Ground-water

recharge

Filtration (membrane, sand)

Biologi-cal Treat-

ment

Water (drinking

water)Nutrient

Energy

Fertilizer (N, P, K)

Soil amend-

mentAnaerobic treat-ment

(biogas)

Aerobic treat-ment

(composting)

Grey-water

Black-water

Organic

waste

Ecological Sanitation: Source Separation is often practiced

faeces(brownwater)

anaerobic digestion,drying, composting,mixing with organic

solid waste

biogas, soil

improvement

constructedwetlands, gardening, wastewater ponds,

biol.treatment

Greywater (showers, washing,

etc.)

irrigation,

groundwater recharge ordirect reuse

urine (yellowwater)

liquid or dry fertiliser

hygienisation by storage or

drying

filtration,biol. treatment

rainwater

water supply,groundwater

recharge

treatment

utilisation

substances

Advantages of ecosan Systems

• Improvement of health

• Promotion of recycling

• Conservation of resources

• Preference for modular, decentralised partial-flow systems

• Contribution to the preservation of soil fertility

• Improvement of agricultural productivity and hence contributes to food security

• Increasing user comfort/security, in particular for women and girls Promotion of a holistic, interdisciplinary approach.

• Cyclic Material-flow instead of disposal.Source: (18)

Source: (18)

There is not only one Ecosan Technology…

…many technology components can be used for Ecosan!

Urine-diversion flush toilets

Urine-diverting dehydration toilets

Constructed Wetlands

Toilet-linked Biogas Plants

…and many more!

Decentralized Wastewater Treatment Systems

Conclusion – Ecological Sanitation Approach

Ecosan is…

...not only about waterless toilets

…not a certain technology

...not only about wastewater treatment…

J. Heeb

Conclusion - Ecological Sanitation Approach

Ecosan…

…regards all (dry and wet) “wastes” as resources

…is all about reuse, recovery and recycling of nutrients & water

…is a new holistic

way of thinking,

not a specific

technology!

Ecosan Training Course

Capacity Building for Ecological Sanitation in India

Thank you very much for your attention!

Michael Kropac, seecon international, Switzerland

++ References

(1) Werner, Ch. Panesar, A. Bracken, P., Mang, H.P., Huba-Mang, E. Gerold, A.M., Demsat, S., Eicher, I. (GTZ) (2004): An ecosan source book for the preparation and implementation of ecological sanitation projects. 3rd draft, February 2004. GTZ.

(2) Environmental Sanitation Working Group of the Water Supply and Sanitation Collaborative Council WSSCC (2004): Bellagio statement: Clean, healthy and productive living: A new approach to environmental sanitation.

(3) Evans, B. (2004): Whatever Happened to Sanitation? - Practical steps to achieving a core Development Goal. Millennium Project: Task Force on Water and Sanitation in March 2004.

(4) Werner, Ch., Mang H.-P., Klingel, F. Bracken, P. (2004): General overview of ecosan. PowerPoint-Presentation. Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH ecological sanitation programme.

(5) Evans, R. (1990): Tod in Hamburg. Stadt, Gesellschaft und Politik in den Cholerajahren 1830-1910. Rowohlt. (6) Ecosanres (2005): Fact Sheet No 1: The Sanitation Crisis. Ecological Sanitation Research/SIDA, Sweden. Available at:

http://www.ecosanres.org/PDF%20files/Fact_sheets/ESR1lowres.pdf (Accessed 9.11.2005).(7) NOVAQUATIS, EAWAG (2005): Nova 5 Workpackages: Micropollutants. Available at:

http://www.novaquatis.eawag.ch/Downloads/Nova_05.pdf (Accessed 27.10.2005).(8) Encyclopaedia Britannica Online: Eutrophication http://search.eb.com/eb/article-9033307?query=eutrophication&ct= (Accessed

27.10.2005)(9) GTZ: ecosan – Ecological Sanitation: Shortcomings of conventional sanitation systems. Available at:

http://www2.gtz.de/ecosan/english/thema1.htm (Accessed 9.11.2005).(10) Deplazes, G. & Hieber, M (2005): Handlungsbedarf beim Abwasser im ländlichen Raum. – In: Schweizer Gemeinde 10/2005.(11) BUWAL Bundesamt für Umwelt, Wald und Landschaft (2005): http://www.trinkwasser.ch/dt/html/bildergallerie/frameset.htm

(accessed 28.09.2005)(12) Alsén, K.W. & Jenssen, P.D. (2004): Ecological Sanitation. For mankind and nature. Norwegian University of Life Sciences. (13) Encyclopaedia Britannica Online: Runoff. http://search.eb.com/eb/article-9064427?query=runoff&ct= (Accessed 11.11.2005)(14) Ecosanres (2005): Fact Sheet No 2: The Main Features of Ecological Sanitation. Ecological Sanitation Research/SIDA, Sweden.

Available at: http://www.ecosanres.org/PDF%20files/Fact_sheets/ESR2lowres.pdf (Accessed 9.11.2005).(15) Esrey, S. A., Andersson, I. Hillers, A., Sawyer, R. (2001): Closing the Loop. Ecological Sanitation for Food Security. Publications on

Water Resources No. 18. UNDP, SIDA. (16) Jenssen, P. D. (2005): Ecological Sanitation – a technology assessment. Norwegian University of Life Sciences. PowerPoint-

Presentation, held at the 9th. International conference on ”Ecological Sanitation” Mumbai India, November 25th, 2005. (17) Werner, Ch., Abdoulaye Fall, P., Schlick, J. & H.-P. Mang (2003): Reasons and principles for ecological sanitation. 2nd

International Symposium on Ecological Sanitation, April 2003. Lubeck, Germany. Available at: www.gtz.de/de/dokumente/en-ecosan-reasons-and-principles-2004.pdf

(18) GTZ: ecosan – Ecological Sanitation: Advantages of ecosan concepts. Available at: http://www2.gtz.de/ecosan/english/thema2.htm (Accessed 9.11.2005).

(19) Werner, Ch. (2004):Ecological sanitation – principles, urban application and challenges. PP-Presentation at the UN Commission on Sustainable Development, 12th Session - New York, 14-30 April 2004. Available at: www2.gtz.de/ecosan/download/CSD12-ecosan-werner.pdf