ECOlogical SANitation - closing the loop between waste to food...
- Its a concept of producing food material from the waste material produced from the household ...Form of pollution management technique.
2. The Challenge
• Cities, towns and rural areas – people live and raise their children in highly polluted Envt.
• Cities expanded and population increases – Situation will grow worse and need for safe,
sustainable and affordable sanitation systems.
• Environmental pollution = The intake capacity and overloading of the natural environment -
Toxic algal bloom.
• Limitation of natural resources - Peak phosphorus crisis
• The main focus of sanitation has changed from health aspects to the reduction of environment
impacts.
Every 20 seconds a child dies as a result of poor sanitation.
2.5 billion people still lack improved sanitation. 1.1 billion people
still practice open defecation, that’s 15% of the world population.
3. Perceptionof faecal material, which is
considered as repulsiveand not to be
touched.
The design of the technologies is - based
on the premise that excretaare waste and
that waste is only suitable.
Small quantitiesof potentially harmful
substances with large amounts of water -
magnitude of the problem is multiplied.
Conventional sanitation concepts
4. 400-500 l of urines and 50 l of faeces
- flushed away with 15,000 l of pure water.
Via a pipe system the bath, kitchen and laundry waste (Grey water)-add up another 15,000-30,000 l
for each person / year.
Pollution Magnification
Final destiny - No treatment
Out of about 38000 million liter per day of sewage generated treatment
capacity exists for only about 12000 million liter per day – CPCB, 2010.
5. • The pit toilet is based on containment and
indefinite storage of human excreta.
• Common and Simple sanitation system in the
world.
• Drawbacks :
- Can’t used in crowded areas, rocky ground and
the place where groundwater level is high.
- Over flow during rainy season, fly breeding and
pit collapse.
Approximately 1.77 billion people around the world use pit latrines // 2 billion people depend on
groundwater for their primary drinking water supply
Groundwater contamination from pit latrines frequently detected it, and studies observed travel distances of
up to 25 m, 50 m, and 26 m for unsafe concentrations of bacteria, viruses, and chemicals, respectively ( Graham
et al., 2013).
9. History
The term "ecosan" was first used in about the 1990s (or perhaps even late 1980s) by an NGO in
Ethiopia called Sudea - urine-diverting dry toilets coupled with reuse activities.
It was further used and defined by Swedish experts - Stockholm Environment Institute which had
a program, called EcosanRes, running from 2001-2011 where they did research on ecosan.
‘Safety of reuse’ - taken up in the WHO Guidelines from 2006.
The recovery and use of urine and feces in "dry sanitation systems", i.e. without sewers - reuse
was not limited to agricultural production.
The Roman – bleaching attribute of the ammonia within urine and used it to whiten clothing.
The most renowned example of the organised collection and use of human excreta to support
food production is that of China - "night soil" as a fertilizer - the collection of excreta from cities
and its transportation to fields.
The Chinese were aware of the benefits of using excreta in crop production more than 2500 years
ago.
11. Potential of Sewage
• N and P
Source: UN Department of Technical Cooperation for Development (1985)
• The nutrient value of this water is between Rs 75 per hectare per annum and Rs 400 per hectare per annum.
•
• The only way out is to set up systems wherein this water can be used for irrigation and fertilisation in fields
and horticultural areas.
• The fertilizers along with wastewater worth Rs 1091.20 million are discharged in to the coastal waters from
coastal cities and towns annually (CPCB, 2010).
Category (mg/l) Strong Medium Weak
Nitrogen (as N) 85 40 20
Phosphorus (as P) 20 10 6
12. Potential of Urine
Adult may produce 400 l of urine/year – containing 4 kg N, 0.4 kg P and 0.9 kg K.
Readymade form
Heavy metal concentration is much lower than the fertiliser.
Urine contains most of the nutrients but generally no pathogens – so no further processing needed.
Application
# Open soil – Undiluted form
# Plants – Diluted form to prevent scorching (one part to 2-5 parts of water)
Potential of Faeces
Consists mainly of undigested organic matter mainly carbon.
25-50 kg/person/year – containing up to 0.55 kg N, 0.18 of P and 0.37 kg of K.
Fewer nutrients than urine, they are valuable soil conditioner.
13. options - vision
Expand existing sanitation approaches, with all limitations and weaknesses.
Seek entirely new solution
3 Fundamental Aspects
Rendering human excreta safe
Preventing pollution rather than attempting it after we pollute
Using safe products of sanitized human excreta for Agri purposes
14. Ecosan
• It is a cycle – a sustainable, closed loop system.
• It treats human excreta are processed on site and then, if necessary further processed off site until
they are completely free of disease organisms.
• …… Is not a specific technology, but a new philosophy of dealing with what is presently
regarded as waste and wastewater for disposal
*Resource minded not Waste minded
• The principle underlying Ecosan are not novel.
• Widely used in East and South East Asia.
15. Resource Recovery
Criteria
1.Prevent Diseases
2.Affordable
3.Protect the event
4.Acceptable
5.Simple
Diversion – Urine diverted away from faeces
Separation– Urine & faeces are mixed together then separated from each other
Combined processing - Urine and faeces are mixed together, processed and their resource value is captured together
Urine-Typhoid, Paratyphoid and bilharzia
Human excreta – Including diarrhoea and ,malnutrition
4 main groups : Bacteria, Viruses, Protozoa and Helminths
16. Stepwise pathogen destruction
1. Keep the volume of dangerous material small – by diverting the urine and not adding (flushing) water.
2. Prevent the dispersal of material containing pathogen - by storing it in some kind of secure device until safe for
recycling.
3. Reduce the volume and weight of pathogenic material – by dehydration and decomposition.
4. Reduce pathogens to a harmless state
Primary-dehydration/decomposition
Secondary-further dehydration/high temperature and lime addition
Tertiary-incineration
18. 2. Sanitation system based on Dehydration
Removal of water, moisture content brought down to below 25%
The Double vault Dehydrating Toilet in Vietnam
The toilet is built entirely above the ground with the processing chambers.
Before using first time the vault is covered with powdered earth.
After each use people sprinkle two bowls of ashes over the faeces., ashes absorb moisture, neutralize bad odours and
make the faeces less attractive to flies.
The Indoor, Dehydrating toilet in Ladakh, India
Ladakh- Himalayan region dry highland at an altitude of 3,500 m.
Toilet – upper floor
Drop hole leads to ground floor
Loads of soil into the room – Winter season supply
20. The double vault toilet in India (Kerala)
Vietnamese sanitation system has been adopted.
Toilets are built for about USD 100 (INR 4,500), Including superstructure.
Over each vault there is a drop hole for faeces and a funnel for urine. Between two vault there is a trough over which
anal cleaning is performed.
The water used for anal cleaning and the urine flow into the evapo-transpiration bed planted with veg. plants.
21. 3. Sanitation system based on Decomposting
Human excreta along with additional bulking agents (Vegetables, straw, peat
moss, wood shaving etc).
O2 required – maintain aerobic condition
Moisture – 50-60 %
C:N balance – 15:1 to 30:1
Temp - > 15 deg C
22. The Clivus multrum single vault composting toilet in Sweden
50 years ago
Single vault composting toilet with combined processing
of Urine, Faeces and Organic matter.
Process reduce the heap to less than 10% of the original
volume.
Starter bed 0.4 m thick layer of peat moss and 0.2 layer of
garden soil rich in humus.
Humus – 10 to 30 l/person/year.
25. Kaliyapalayam Village (Tamil Naidu) – Case Study of Ecosan
Located on the Cauvery River, in the Tirupur district in Tamil Nadu.
launched in 2002 to reduce water use in sanitation, prevent water pollution due to open defecation (as the water table is
high), by the Society for Community Organization and Peoples Education (SCOPE).
Initially, the gram sabha passed a resolution to construct eco-san toilets in 18 households - demand driven approach.
stakeholders were consulted at each stage of the project.
The concept was welcomed and quickly accepted by the residents.
Initially, a 2-in-1 model was adopted where the wash water and the urine were mixed and collected in one chamber and,
faeces were collected in the other chamber.
Generally satisfied with the system. Based on their feedback of the residents, the 2-in-1 model was replaced with a 3-in-1
model in which the urine, faeces and wash water are collected separately.
26. Contd…
The high initial cost of eco-san toilet of about Rs 18,000 is offset by long-term socio-economic and health
benefits. Wash water applied to banana trees next to toilets assures irrigation at no cost, while the sale of
manure and urine for agriculture contributed towards overall income for the village.
These benefits provide 200 per cent return on the investment over lifespan of a toilet.
This proves the value of eco-san as a means to close the nutrient loop in solid and liquid waste in a safe and
hygienic manner.
Augmenting income both directly (sale of manure and urine) and indirectly through increased farm output.
SOURCE: Nitya Jacob & Amandeep Kang, Centre for Science and Environment New Delhi,
February 2013 (greening rural development programmes by the Ministry of Rural Development, GoI) )
27. Sensitivity of Sanitation system
• More complex than drop and store but infinitely less complex than
Flush and discharge.
• Lack of participation.
• Lack of understanding.
• Defective materials and workmanship.
• Improper maintenance.
28. Advantages of Ecosan
1. Protect our environment, ground water, streams, lakes and the sea from faecal contamination.
2. Allows us to make use of the high fertilizer value of urine. 400 to 500 l of urine produced by each
person/yr contains enough plant nutrients to grow 250 kg of grains enough to feed one person for one
year.
3. Human faeces turned into valuable soil conditioner.
4. Pathogen destruction as well as handling is safer, easier and less costly.
5. Large scale recycling would reduce the greenhouse effect.
6. It is often said that one can’t have good toilet without water. This is because some sanitation depends on
water for transport faeces and urine to offsite location. But for Ecosan water no need.
29. Disadvantages
1. Users need to be taught how to use them properly.
2. Faeces need to be treated in the correct manner, otherwise they pose a
health risk.
3. High density urban areas don't always have the capacity to use the by
products produced.
30. SUMMARY OF ECOSAN CONCEPTS
Ecossan
latrines
Manure reused
in Agriculture
Permanent sanitation
option (if double vault
is used)
Reduces ground water
pollution
Use of Ash & soil
reduces smell
Improves soil fertility
Reduce the
dependency of fertilizer
Contaminant of
waterbodies during floods
Houseflies and bad odours
if not properly managed
Pathogens to those
emptying contents of pit
Pathogens to those
handlers of manure
Pathogens to those
consumers
Pathogens to people
through the rnvt.
Contamination
Known
Effect of PH,
Temperature, NH3 &
time on survival of
experimental situations
Pathogen survival taken
into account
Condition in real latrine
situation
Continued
improvement
interms of quality of
the manure
High adoption rate of
ecosan
Imprved health
benefits and
sanitation of the
people.
ECOSAN
BENEFITS RISKS RESEARCH
OUTPUTS
31. References
1) Esrey S et al. (1998). Sida, Stockholm.
2) Gunder Langergreber., Elka muellegger. (2005). Ecological Sanitation – a way to
solve global sanitation problems?. Environment International, (31) pp 433-434.
3) Ecosan – Clsing the loop Proceedings of the 2nd international symposium, Eschborn
(2004).
4) Ecosan – closing the loop in wastewater management and sanitation. Proceedings of
the 2nd international symposium, Eschborn (2001).
5) Lucas Denge. (2010). Ecological Sanitaion. green aerovilleportal. Org
6) Kumwenda., Msefula et al. (2014). Sustainable Water and Sanitation services for all
– 37 th WEDC International Conference, Vietnam.