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Ecological sanitation system using human urine as a fertilizer to replenish nutrient-depleted agricultural soil
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Ecological sanitation system using human urine as a fertilizer to replenish nutrient-depleted
agricultural soil This proposal involves an ecological sanitation system which uses urine as fertilizer and
dried fecal matter as a fuel source, and proposes the design of a simple urine-separation toilet system that can be made by
women for their households at minimal cost using recycled plastic containers. In addition to soil replenishment
this proposal also addresses the need for low-cost safe sanitation, and the protection of water supplies. Implementation
of an eco sanitation system has the potential to improve health, nutrition, social and economic conditions, especially for
women in impoverished communities. Ecological Sanitation is based on the philosophy that wastewater is seen as
a source for nutrients for agriculture or as an energy source using the high organic content in excreta. Humanure, the
term for using this waste has been studied for its nutrient potential for soil remediation and for safety of use. The
research has shown that humanure, both urine and feces contain significant amounts of nitrogen, potassium and phosphorous
in a form that plants can absorb easily, and are a viable alternative to commercial fertilizers. In developing countries
with highly pathogenic populations, composting of feces requires skill, has severe health implications if done incorrectly
and requires several years to see results, whereas urine is safer, requires little skill and produces almost immediate results.
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There are a number of designs for urine separation toilets/dry toilets that direct the urine and feces into separate
holding tanks. The current designs require the construction of an elevated platform to accommodate tanks below
the toilets for varying commercial pedestal and squat pan toilets accommodating a sitting or squat position only. Complete
separation of fecal matter and urine is safer, more efficient, and a more pleasant experience especially in public toilet
situations, due to the higher ratio of urine deposits to feces deposits per person per day. Separation also avoids possible
contamination of the urine by fecal matter, a reduction of flies, and reduction of odors. In my opinion the deterrents
to the adoption of Eco Sanitation systems is cost, skill and time required to construct the systems. Designs are needed
that require little skill, are inexpensive or free to build, and can be constructed quickly. As an architect/ designer
with a sculpture background and training in green building, regenerative design and permaculture, I think my love for
problem-solving and low tech solutions gives me the skills to tackle the design problem. I have done some preliminary
experiments using recycled containers (video and photographs can be viewed at and am currently researching and testing design
ideas in rural Mexico. My plan for implementation is to continue research in Africa as to design possibilities using
locally available materials, to research social customs related to sanitation and the use of urine as fertilizer and feces
as a fuel source, and to begin working on implementation strategies based on that research. I have the unique
opportunity of meeting with farmers across African and to visit farms in Malawi, Zimbabwe and South Africa as a participant
of the Permaculture Convergence, a bi-annual meeting of Permaculture experts from around the world. The event will be
held in November 2009 in Malawi, and I am looking forward to attending a hosted three week tour of farms in Malawi, Zimbabwe
and South Africa. The Convergence is an excellent opportunity to disseminate information on Eco Sanitation systems through
a panel presentation, and I hoping to have the resources to arrive early to construct a prototype toilet diversion system
on the site to promote participation and dissemination of the concepts and to explore the cultural issues for different areas
of Africa. Needs Assessment- The majority of people in sub-Saharan
African are depend on agriculture for their livelihoods. Africa cannot produce enough food to keep pace with its needs, and
per capita food production is declining. Low soil fertility, including depleted nutrients, organic matter and poor water holding
capacity are the major factors responsible for depressed yields on small-scale farms across Africa. Severe soil depletion
results in a vicious cycle of declining yields, deepening poverty, and increased degradation of the natural resource base
that farmers depend upon. Subsistence farmers have little access to fertilizers, as soils decline and farm yields drop,
impoverished farmers move on to clear forests and savannah, where the cycle begins again. Fertilizers enhance crop growth
and increases nutrition for those who depend on subsistence farming. Access to fertilizers which are free, plentiful,
locally available, and easily applied are needed to create healthy, fertile soils that retain nutrients, water, essential
microbes and other soil organisms that promote plant growth and are vital for sustained agricultural development. Farmers
reliant on external inputs are in need of a commercial fertilizer replacement as oil prices escalate the price of oil-based
fertilizers rise. A more sustainable source of fertilizer is necessary as peak oil forces an end to the affordability
of these commercial fertilizers. The salts in chemical fertilizers have added to the depletion of natural
micro flora, and have increased water use. Sanitation- Sanitation can improve social and economic
conditions especially for impoverished communities. In sub-Saharan Africa, a baby's chance of dying from diarrhea is almost
520 times that of a baby born in Europe or the United States. Poor sanitation and hygiene and unsafe water claim the lives
of an estimated over 1.5 million children under the age of five every year. World Health Organization statistics indicating
that in 38 of the 46 African countries more children under the age of five die from diarrhea than HIV/AIDS. Other indicators
of health risks associated with poor sanitation are the frequency of related parasites that have human fecal origin - about
1 billion people are infected with roundworm and 700 million with hookworm. Conventional pit latrines contribute to
groundwater pollution and can be health and environmental hazards and face a variety of problems like pit collapsing and flooding.
Also the need for digging of new pits once the old one is filled is considered a drawback of this conventional technique. Urine
as a fertilizer- Urine is a locally produced resource that is free. As a fertilizer it is effective, is a high
quality fertilizer, urine is sterile and requires no processing other than dilution, is readily available, can be used immediately
or stored, rapid acting, and is easily applied. Urine provides a constant supply of fertilizer, instead of the annual
or semi-annual composting systems that require physical labor to aerate and require management. As a fertilizer, urine
is rich in nitrogen and also contains substantial amounts of phosphorus and potassium.
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| Study at Arba Minch University showing impact of urine of corn crop |
A family
of four produces enough urine to fertilize 1/3 of an acre at a rate compared to the application of 100kg per hectare in developed
countries -note that Africa currently has the lowest fertilizer use in the world at 8.5kg per hectare. The use of urine
as fertilizer has been studied by Arba Minch University in Ethopia and the Sodo Agricultural Department investigated
the use of human urine as fertilizer for different crops. Their research indicates equal or higher yields of maize and wheat
when fertilized with urine when compared with the applications of chemical fertilizer. The use of dried feces as a fuel source Due to the difficulty
in safely using fecal matter as a soil additive, I propose the use of dried feces as a fuel source. When using humanure
is from a highly pathogenic population a thermophilic composting technique must be used where the temperature rise in
the compost is sufficient to kill pathogens and feces, and then aged for one to two years to ensure pathogens have been eliminated.
This process requires skill and managemet over time. Desiccation happens naturally in hot dry climates if the feces
are first covered with wood ash after deposit, and then exposed to the air and sun. Addition of ash facilitates pathogen inactivation
and decrease the risk for disease transmission during handling and reuse of the material. Desiccation of the material and
low moisture contents aid to pathogen inactivation. Esrey et al. (1998) suggested that there is rapid pathogen destruction
at moisture levels below 25%, and that this level should be aimed for in ecological sanitation toilets that are based on dehydration.
Low moisture content is also beneficial in order to reduce smell and fly breeding. The ash created by the burning of
feces provides a fertilizer with phosphorous and potassium. Advantages of
dry toilet systems In a dry/urine diversion toilet system, urine is separated
from feces which reduces the amount of fecal material to be handled and lowers the risk for disease transmission and
reduces odors and flies. Fecal matter is collected separately in an above-ground closed compartment that prevents leakage
into the groundwater and the surrounding environment. Questions
and Answers that provide additional information Abena Asare Cannot wait to see the pictures!
This is a fascinating idea and proposal.
Have you done any
research about the social acceptability/feasibility of urine as a fertilizer in different locales? where would you begin with
dissemination, education, and training after designing the dry toilet? GailSwithenbank Hi Abena,
Thank you so much for your comments.
I have posted a youtube video of the
design at- www.youtube.com/watch?v=LSXvY_NWvso Research by Arba Minch University in Ethopia with farmers in the Sodo Agricultural Department indicated
that the farmers had no issues with adoption of using urine as a fertilizer once they saw the benefits in terms of yield.
I do need to do some research on the cultural acceptability or possible taboos of using urine, and of collection methods in
different areas. I plan to be in Malawi, Zimbabwe and South Africa for a tour of local farms and education programs in November
as part of the Permaculture Convergence in Malawi, this will be an excellent time to do this kind of research as well as an
opportunity to look at availability of recycled materials. I am hoping to do some experimentation and training as we travel
to develop the process as well as to research some other ideas.
AlanRye This idea has merit. The use of urine as a fertiliser requires some understanding. It's low in phosphorus,
and urea (the main source of nitrogen) rapidly degrades to ammonia unless it is stabilised by refrigeration or other means.
Ammonia can be an effective fertiliser, but it is alkaline and volatile. If the urine is used soon after collection, there
are probably few issues. Monitoring of soil nutrients and pH would be helpful. Hi Alan,
According
to Dr. Peter Morgan- "Urine contains a lot of nitrogen and also phosphorus and potassium in smaller quantities, nutrients
which are very valuable to plant growth. The nitrogen found in abundance in urine is good for plant growth because it helps
to build protoplasm, protein and other components of plant growth. It certainly promotes leafy growth. Leaves become more
numerous, go greener and larger and more fleshy with urine application. Phosphorus is important in the root formation, ripening
of fruits and germination of seeds, although the percentage of phosphorus compared to nitrogen in urine is low. Potassium
is also essential for promoting good fruit (and flower) development. Plants differ in their requirements, but overall plants
fed with some urine grow better than plants which never come into contact with urine. Urine is particularly valuable for grasses
like maize and leafy green vegetables, and onions, which respond to the high nitrogen content of urine.
When applied
to the soil the urea (a small organic molecule) in urine changes into ammonia ions which can be transformed into ammonia gas,
which can evaporate and be lost or, in the soil, can be converted by autotrophic bacteria (Nitrosomonas) into nitrite ions
and then Nitrobacter into nitrate ions which can be taken up by the plant. The conversion is thus dependent on these bacteria
being in the soil. The process takes place in less than two weeks and often within a few days. It is the nitrogen in the nitrate
and the ammonia ions which are available to plants, thus the urea in urine must be transformed before it becomes useful as
a "plant food." The nitrite ions, present during the conversion, can be toxic to plants, but the period is brief
and normally there is little effect on plant growth.
According to Wolgast (1993) one litre of urine contains 11gms nitrogen,
0.8 gms. phosphorus and 2 gms. potassium. That is a ratio of NPK of about 11:1:2. If 500 liters of urine are produced by each
person per year, that amounts to the equivalent of 5.6 kg nitrogen, 0.4 kg phosphorus and 1.0 kg potassium.
Dr. Peter
Morgan has been working with humanure in Zimbabwe for a number of years
link to his article on urine in agriculture-
www.ecosanres.org/pdf_files/PM_Report/Chapter_10_The_usefulness_of_urine_a.pdf
Hi Gail thanks so much for sharing. I read your proposal
and just brought a few questions to mind. Are folks already using human urine as a fertilizer? What happens to the feces?
I know in theory that when an human is healthy their urine is sterile, but I also know (from my father, a urologist) that
if folks aren't healthy, their urine in turn, may or may not be sterile. How to do folks work around those sorts of issues?
Very interesting idea though. I'd love to see some of your designs. Shelton GailSwithenbank Hi Shelton According to the Swedish Institute for Infectious Disease "Several
types of bacteria may cause urinary tract infections. The environmental transmission of these are normally of low importance.
E. coli is the most common cause of urinary tract infections, where certain clones may also be associated with gastrointestinal
infections. The pathogens traditionally known to be excreted in urine are Leptospira interrogans, Salmonella typhi, Salmonella
paratyphi and Schistosoma haematobium (Feachem et al., 1983). There is a range of other pathogens that have been detected
in urine but their presence may not
be considered significant for the risk of environmental transmission of disease.
For the urine, mainly temperature and a elevated pH in combination with ammonia have been concluded to affect the inactivation
of microorganisms. So far, storage at ambient temperature is the only method practiced to sanitize urine. Increased temperature
or pH of the collected urine would further speed up the inactivation of potential pathogens. Recommended storage time at temperatures
of 4-20°C varies between one and six months for large-scale systems depending on the type of crop to be fertilized. For
single households, urine could be applied to any crop without storage as long as one month passes between fertilization and
harvest if fecal cross-contamination is avoided. Dilution of the urine should be avoided.
Guidelines on the Safe Use
of Urine and Feces in Ecological Sanitation Systems by Caroline Schönning and Thor Axel Stenström from the Swedish
Institute for Infectious Disease Control (SMI
http://www.ecosanres.org/pdf_files/ESR_Publications_2004/ESR1web.pdf Shelton's question addressed the use of feces. The use of fecal matter as a soil additive is complicated when humanure
is from a highly pathogenic population. A thermophilic composting technique must be used where the temperature rise in the
compost is sufficient to kill pathogens and feces must be composted and then aged requiring a one to two years cycle. Because
of this issue I propose the use of dried feces as a fuel source. Desiccation happens naturally in hot dry climates if the
feces are first covered with wood ash after deposit, and then exposed to the air and sun. Addition of ash facilitates
pathogen
inactivation and decrease the risk for disease transmission during handling and reuse
of the material. Desiccation of
the material and low moisture contents aid to pathogen inactivation. Esrey et al. (1998) suggested that there is rapid pathogen
destruction at moisture levels below 25%, and that this level should be aimed for in ecological sanitation toilets that are
based on dehydration. Low moisture content is also beneficial in order to reduce smell and fly breeding.
The ash created
by the burning of feces provides a fertilizer with phosphorous and potassium.
The heat content of human waste when
totally dry, is about 4000-7000 Btu/lb, which is equivalent in heat to lignite coal--also, appropriately, called brown coal.
http://www.straightdope.com/columns/read/2240/can-animal-including-human-manure-be-used-as-fuel
MaggieSharzan Great proposal. I love the simplicity of the design, and the fact that it could be constructed by any
skill level. I can imagine school children in Africa making the system as a school project and then using the urine on their
school garden or for use by a local farmer. It makes so much sense, I wonder why I haven't heard much about using urine as
fertilizer through the Permaculture Community since there is so much emphasizes on soil regeneration. Your presence at the
Permaculture Convergence should help to educate that community, they sponsor local farmers to attend from all over Africa,
as well as the participants from other countries around the world, you could make a great impact! GailSwithenbank Hi Maggie,
Great to hear from another Permaculture enthusiast! I wondered about the lack of information
about urine as fertilizer from the Permaculture community as well. I studied with Bill Mollison and Geoff Lawton, and have
spent time at both of their farms in Australia and neither separate urine. Geoff has a humanure system, which involves composting
in a dual chamber, then transfers the compost to a vermacomposting system to be further processed. Both Geoff and Bill also
rely heavily on green manure, and nitrogen fixing trees and plants, and fertilizer from their cows and horses as well as chicken
and pig tractors to manure the soil and scratch/dig it up.
Bill Mollison was very actively teaching Permaculture in
many parts of sub-Saharan Africa starting in 1987, and left many students and demonstration sites to continue teaching his
regenerative techniques. It is very possible that the idea of using urine as a fertilizer could be spread through Africa by
the Permaculture community through this Convergence, it is the first time the Permaculture community has met in Africa. I
am hoping to have the funds to arrive early and to set up a demonstration model so the participants can experience the toilets
during the Convergence and the tour of Permaculture sites across Malawi, Zimbabwe and South Africa will be a great chance
to further the designs, and to test them in a real-life situation.
Dr. Peter Morgan is in Zimbabwe, he is the leading
expert on humanure - perhaps a short sidetrip while in Zimbabwe.
BobbieS Can someone explain Permaculture GailSwithenbank Permaculture design principles are based on the work of Bill Mollison, a biologist from Australia will
field experience in forest regeneration, and the regeneration of macro-fauna, food chains, and water conditions of the inland
waters and estuaries of Tasmania. By studying natural ecosystems, Mollison began to understand the necessity for the conscious
design and maintenance of agriculturally productive ecosystems that mimic and have the diversity, stability, and resilience
of natural ecosystems. An example of his regenerative design principles which he calls Permaculture (derived from the words
- Permanent/Agriculture) developed to address the issues of contemporary agriculture and climate change, is a system where
70% of cropland is devoted to forage farming, replacing animal forage grains with nitrogen fixing tree crops, increasing forest
cover, adopting low to no tillage on remaining croplands, retrofitting houses for energy conservation, and producing some
(if not all) fuel on the farm.
Mollison introduced Permaculture design principles to Africa beginning in 1987
when traveled through Africa meeting with local farmers and surveying ecological issues. During his many trips he trained
farmers from South East and South Africa in sustainable farming principles. Many of Mollison's students returned to their
villages and towns, and shared their training with local farmers and students who have continued experimenting and developing
these sustainable farming principles for the past 22 years. The Convergence in Africa will bring people from these areas across
Africa and from other developing and developed countries around the world together to share and compare experiences, the successes
and failures over the years of experimentation. Links and additional information- EcoSan Res (Environmental Sanitation Research Program)
promotes environmental Sanitation in the developing world, and has done great research on humanure systems and use of urine
and feces as fertilizer. www.ecosanres.org/ Guidelines on the Safe Use of Urine and Feces in Ecological Sanitation Systems by Caroline Schönning
and Thor Axel Stenström from the Swedish Institute for Infectious Disease Control (SMI
http://www.ecosanres.org/pdf_files/ESR_Publications_2004/ESR1web.pdf Dr. Peter Morgan has been researching and promoting humanure from his location in Zimbabwe
for a number of years. link to his article on urine in agriculture- www.ecosanres.org/pdf_files/PM_Report/Chapter_10_The_usefulness_of_urine_a.pdf
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A family of four produces enough urine to fertilize 1/3 of an acre at a rate compared to the application of 100kg per
hectare in developed countries -note that Africa currently has the lowest fertilizer use in the world at 8.5kg per hectare.
The use of urine as fertilizer has been studied by Arba Minch University in Ethopia and the Sodo Agricultural Department
investigated the use of human urine as fertilizer for different crops. Their research indicates equal or higher yields of
maize and wheat when fertilized with urine when compared with the applications of chemical fertilizer. The use
of dried feces as a fuel source Due to the difficulty in safely using fecal matter as a soil additive, I
propose the use of dried feces as a fuel source. When using humanure is from a highly pathogenic population a thermophilic
composting technique must be used where the temperature rise in the compost is sufficient to kill pathogens and feces, and
then aged for one to two years to ensure pathogens have been eliminated. This process requires skill and managemet over time.
Desiccation happens naturally in hot dry climates if the feces are first covered with wood ash after deposit, and then
exposed to the air and sun. Addition of ash facilitates pathogen inactivation and decrease the risk for disease transmission
during handling and reuse of the material. Desiccation of the material and low moisture contents aid to pathogen inactivation.
Esrey et al. (1998) suggested that there is rapid pathogen destruction at moisture levels below 25%, and that this level should
be aimed for in ecological sanitation toilets that are based on dehydration. Low moisture content is also beneficial in order
to reduce smell and fly breeding. The ash created by the burning of feces provides a fertilizer with phosphorous and
potassium. Advantages of dry toilet systems In a dry/urine diversion
toilet system, urine is separated from feces which reduces the amount of fecal material to be handled and lowers the
risk for disease transmission and reduces odors and flies. Fecal matter is collected separately in an above-ground
closed compartment that prevents leakage into the groundwater and the surrounding environment. Questions
and Answers that provide additional information Abena Asare Cannot wait to see the pictures!
This is a fascinating idea and proposal.
Have you done any research about
the social acceptability/feasibility of urine as a fertilizer in different locales? where would you begin with dissemination,
education, and training after designing the dry toilet? GailSwithenbank Hi Abena,
Thank you so much for your comments.
I have posted a youtube video of the design at- www.youtube.com/watch?v=LSXvY_NWvso Research by Arba Minch University in Ethopia with farmers in the Sodo Agricultural Department indicated that the farmers
had no issues with adoption of using urine as a fertilizer once they saw the benefits in terms of yield. I do need to do some
research on the cultural acceptability or possible taboos of using urine, and of collection methods in different areas. I
plan to be in Malawi, Zimbabwe and South Africa for a tour of local farms and education programs in November as part of the
Permaculture Convergence in Malawi, this will be an excellent time to do this kind of research as well as an opportunity to
look at availability of recycled materials. I am hoping to do some experimentation and training as we travel to develop the
process as well as to research some other ideas.
AlanRye This idea has merit. The use of urine as a fertiliser requires some understanding. It's low in phosphorus, and urea
(the main source of nitrogen) rapidly degrades to ammonia unless it is stabilised by refrigeration or other means. Ammonia
can be an effective fertiliser, but it is alkaline and volatile. If the urine is used soon after collection, there are probably
few issues. Monitoring of soil nutrients and pH would be helpful. Hi Alan,
According to Dr. Peter Morgan- "Urine
contains a lot of nitrogen and also phosphorus and potassium in smaller quantities, nutrients which are very valuable to plant
growth. The nitrogen found in abundance in urine is good for plant growth because it helps to build protoplasm, protein and
other components of plant growth. It certainly promotes leafy growth. Leaves become more numerous, go greener and larger and
more fleshy with urine application. Phosphorus is important in the root formation, ripening of fruits and germination of seeds,
although the percentage of phosphorus compared to nitrogen in urine is low. Potassium is also essential for promoting good
fruit (and flower) development. Plants differ in their requirements, but overall plants fed with some urine grow better than
plants which never come into contact with urine. Urine is particularly valuable for grasses like maize and leafy green vegetables,
and onions, which respond to the high nitrogen content of urine.
When applied to the soil the urea (a small organic
molecule) in urine changes into ammonia ions which can be transformed into ammonia gas, which can evaporate and be lost or,
in the soil, can be converted by autotrophic bacteria (Nitrosomonas) into nitrite ions and then Nitrobacter into nitrate ions
which can be taken up by the plant. The conversion is thus dependent on these bacteria being in the soil. The process takes
place in less than two weeks and often within a few days. It is the nitrogen in the nitrate and the ammonia ions which are
available to plants, thus the urea in urine must be transformed before it becomes useful as a "plant food." The
nitrite ions, present during the conversion, can be toxic to plants, but the period is brief and normally there is little
effect on plant growth.
According to Wolgast (1993) one litre of urine contains 11gms nitrogen, 0.8 gms. phosphorus and
2 gms. potassium. That is a ratio of NPK of about 11:1:2. If 500 liters of urine are produced by each person per year, that
amounts to the equivalent of 5.6 kg nitrogen, 0.4 kg phosphorus and 1.0 kg potassium.
Dr. Peter Morgan has been working
with humanure in Zimbabwe for a number of years
link to his article on urine in agriculture- www.ecosanres.org/pdf_files/PM_Report/Chapter_10_The_usefulness_of_urine_a.pdf
Hi Gail thanks so much for sharing. I read your proposal and just brought a few questions to mind.
Are folks already using human urine as a fertilizer? What happens to the feces? I know in theory that when an human is healthy
their urine is sterile, but I also know (from my father, a urologist) that if folks aren't healthy, their urine in turn, may
or may not be sterile. How to do folks work around those sorts of issues?
Very interesting idea though. I'd love
to see some of your designs. Shelton GailSwithenbank Hi Shelton According to the Swedish Institute for Infectious Disease "Several types of bacteria may cause
urinary tract infections. The environmental transmission of these are normally of low importance. E. coli is the most common
cause of urinary tract infections, where certain clones may also be associated with gastrointestinal infections. The pathogens
traditionally known to be excreted in urine are Leptospira interrogans, Salmonella typhi, Salmonella paratyphi and Schistosoma
haematobium (Feachem et al., 1983). There is a range of other pathogens that have been detected in urine but their presence
may not
be considered significant for the risk of environmental transmission of disease.
For the urine, mainly temperature
and a elevated pH in combination with ammonia have been concluded to affect the inactivation of microorganisms. So far, storage
at ambient temperature is the only method practiced to sanitize urine. Increased temperature or pH of the collected urine
would further speed up the inactivation of potential pathogens. Recommended storage time at temperatures of 4-20°C varies
between one and six months for large-scale systems depending on the type of crop to be fertilized. For single households,
urine could be applied to any crop without storage as long as one month passes between fertilization and harvest if fecal
cross-contamination is avoided. Dilution of the urine should be avoided.
Guidelines on the Safe Use of Urine and Feces
in Ecological Sanitation Systems by Caroline Schönning and Thor Axel Stenström from the Swedish Institute for Infectious
Disease Control (SMI
http://www.ecosanres.org/pdf_files/ESR_Publications_2004/ESR1web.pdf Shelton's question addressed
the use of feces. The use of fecal matter as a soil additive is complicated when humanure is from a highly pathogenic population.
A thermophilic composting technique must be used where the temperature rise in the compost is sufficient to kill pathogens
and feces must be composted and then aged requiring a one to two years cycle. Because of this issue I propose the use of dried
feces as a fuel source. Desiccation happens naturally in hot dry climates if the feces are first covered with wood ash after
deposit, and then exposed to the air and sun. Addition of ash facilitates
pathogen inactivation and decrease the risk
for disease transmission during handling and reuse
of the material. Desiccation of the material and low moisture contents
aid to pathogen inactivation. Esrey et al. (1998) suggested that there is rapid pathogen destruction at moisture levels below
25%, and that this level should be aimed for in ecological sanitation toilets that are based on dehydration. Low moisture
content is also beneficial in order to reduce smell and fly breeding.
The ash created by the burning of feces provides
a fertilizer with phosphorous and potassium.
The heat content of human waste when totally dry, is about 4000-7000
Btu/lb, which is equivalent in heat to lignite coal--also, appropriately, called brown coal.
http://www.straightdope.com/columns/read/2240/can-animal-including-human-manure-be-used-as-fuel
MaggieSharzan Great proposal. I love the simplicity of the design, and the fact that it could be constructed by any skill level.
I can imagine school children in Africa making the system as a school project and then using the urine on their school garden
or for use by a local farmer. It makes so much sense, I wonder why I haven't heard much about using urine as fertilizer through
the Permaculture Community since there is so much emphasizes on soil regeneration. Your presence at the Permaculture Convergence
should help to educate that community, they sponsor local farmers to attend from all over Africa, as well as the participants
from other countries around the world, you could make a great impact! GailSwithenbank Hi Maggie,
Great to hear from another Permaculture enthusiast! I wondered about the lack of information about
urine as fertilizer from the Permaculture community as well. I studied with Bill Mollison and Geoff Lawton, and have spent
time at both of their farms in Australia and neither separate urine. Geoff has a humanure system, which involves composting
in a dual chamber, then transfers the compost to a vermacomposting system to be further processed. Both Geoff and Bill also
rely heavily on green manure, and nitrogen fixing trees and plants, and fertilizer from their cows and horses as well as chicken
and pig tractors to manure the soil and scratch/dig it up.
Bill Mollison was very actively teaching Permaculture in
many parts of sub-Saharan Africa starting in 1987, and left many students and demonstration sites to continue teaching his
regenerative techniques. It is very possible that the idea of using urine as a fertilizer could be spread through Africa by
the Permaculture community through this Convergence, it is the first time the Permaculture community has met in Africa. I
am hoping to have the funds to arrive early and to set up a demonstration model so the participants can experience the toilets
during the Convergence and the tour of Permaculture sites across Malawi, Zimbabwe and South Africa will be a great chance
to further the designs, and to test them in a real-life situation.
Dr. Peter Morgan is in Zimbabwe, he is the leading
expert on humanure - perhaps a short sidetrip while in Zimbabwe.
BobbieS Can someone explain Permaculture GailSwithenbank Permaculture design principles are based on the work of Bill Mollison, a biologist from Australia will field experience
in forest regeneration, and the regeneration of macro-fauna, food chains, and water conditions of the inland waters and estuaries
of Tasmania. By studying natural ecosystems, Mollison began to understand the necessity for the conscious design and maintenance
of agriculturally productive ecosystems that mimic and have the diversity, stability, and resilience of natural ecosystems.
An example of his regenerative design principles which he calls Permaculture (derived from the words - Permanent/Agriculture)
developed to address the issues of contemporary agriculture and climate change, is a system where 70% of cropland is devoted
to forage farming, replacing animal forage grains with nitrogen fixing tree crops, increasing forest cover, adopting low to
no tillage on remaining croplands, retrofitting houses for energy conservation, and producing some (if not all) fuel on the
farm.
Mollison introduced Permaculture design principles to Africa beginning in 1987 when traveled through Africa
meeting with local farmers and surveying ecological issues. During his many trips he trained farmers from South East and South
Africa in sustainable farming principles. Many of Mollison's students returned to their villages and towns, and shared their
training with local farmers and students who have continued experimenting and developing these sustainable farming principles
for the past 22 years. The Convergence in Africa will bring people from these areas across Africa and from other developing
and developed countries around the world together to share and compare experiences, the successes and failures over the years
of experimentation. Links and additional information- EcoSan Res (Environmental Sanitation
Research Program) promotes environmental Sanitation in the developing world, and has done great research on humanure systems
and use of urine and feces as fertilizer. www.ecosanres.org/ Guidelines on the Safe Use of Urine and Feces in Ecological Sanitation Systems by Caroline Schönning and Thor
Axel Stenström from the Swedish Institute for Infectious Disease Control (SMI
http://www.ecosanres.org/pdf_files/ESR_Publications_2004/ESR1web.pdf Dr. Peter Morgan has been researching and promoting humanure from his location in Zimbabwe for
a number of years. link to his article on urine in agriculture- www.ecosanres.org/pdf_files/PM_Report/Chapter_10_The_usefulness_of_urine_a.pdf
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