Ecological sanitation is a system whereby human excreta (humanure) is composted to be re-used as a fertilizer. What!? THAT'S GROSS! Reuse my sh*t?! But the sh*t that comes out of my body is full of harmful pathogens and well, smells like sh*t! Yes, but there is more to your sh*t than you knew about. Alongside the harmful pathogens live millions of productive micro-organisms that, under the right conditions, will kill the harmful pathogens which spread diseases.
For pathogen destruction to occur the excreta must be heated up to 140 F, or thermophilic conditions. Thermophilic conditions are reached by creating a pile of a combination of human excreta with organic material such as grass clippings, rice hulls, or sawdust. It takes at least one year for these conditions to arrive, therefore compost piles need to sit untouched. Remarkably, the organic material removes odors and repels flies and mosquitos.
Furthermore, humanure composting is part of the food cycle.
Appropriate technology.
Our community sits on a river bank and has a high water table, which means if you dig more than 2 feet you will find water. This rules out pit latrines because the pit stays wet, gets full of maggots, smells horrible, and attracts mosquitos. These mosquitos are vectors for disease transmission as they fly around the community after having touched human excreta. People in my community, especially women, hate pit latrines for the smell and therefore either use the river or go out into the jungle.
A composting latrine is built above ground and thus avoids reaching the water table. It is designed to have 2 chambers with a special seat above the chambers that allows the excreta to fall below and also separates urine. Urine is separated in order to keep the pile at around 50% moisture content. A wet environment doesn't allow for the pile to reach thermophilic conditions. After each use the user throws dry material into the chamber. Start by using one chamber for a year or until it is full, then start using the second chamber. Leave the organic material in the first chamber to compost for at least one year. Remove the humanure, dry it out under the sun, and then plant some banana trees!
21st Century technology?
Would you take 2 valuable resources, combine them, to then render both of them as useless? If I gave you 3 gallons of water and fertilizer would you throw them away? Unfortunately, our 'modern' sanitation system does exactly that. Every time we flush the toilet, we combine human excreta and 3 gallons of water to render them both useless. YES I am classifying human excreta not as waste but as a resource.
As volunteers in the field we come up against the cultural / custom battle of how human excreta is perceived all the time in rural communities. However, this battle would be x100000 times harder in the Western world, which can be for the most part considered to be fecophobic. Eastern cultures have been embracing humanure composting for centuries, as they see it as part of an ecological cycle. In fact, in South Korea humanure has been known to be sold on the black market!
Our current sanitation system does work from a public health standpoint. However, it is also consumes are amounts of resources and is completely dependent on the grid. In order for your excreta to move from your house or apartment to waste management facility requires a system that uses a lot of water and a lot of electricity. Humanure composting uses neither water or electricity. Could humanure composting be scaled up to someday make an impact on the global warming challenges we face?
For pathogen destruction to occur the excreta must be heated up to 140 F, or thermophilic conditions. Thermophilic conditions are reached by creating a pile of a combination of human excreta with organic material such as grass clippings, rice hulls, or sawdust. It takes at least one year for these conditions to arrive, therefore compost piles need to sit untouched. Remarkably, the organic material removes odors and repels flies and mosquitos.
Furthermore, humanure composting is part of the food cycle.
Appropriate technology.
Our community sits on a river bank and has a high water table, which means if you dig more than 2 feet you will find water. This rules out pit latrines because the pit stays wet, gets full of maggots, smells horrible, and attracts mosquitos. These mosquitos are vectors for disease transmission as they fly around the community after having touched human excreta. People in my community, especially women, hate pit latrines for the smell and therefore either use the river or go out into the jungle.
A composting latrine is built above ground and thus avoids reaching the water table. It is designed to have 2 chambers with a special seat above the chambers that allows the excreta to fall below and also separates urine. Urine is separated in order to keep the pile at around 50% moisture content. A wet environment doesn't allow for the pile to reach thermophilic conditions. After each use the user throws dry material into the chamber. Start by using one chamber for a year or until it is full, then start using the second chamber. Leave the organic material in the first chamber to compost for at least one year. Remove the humanure, dry it out under the sun, and then plant some banana trees!
Would you take 2 valuable resources, combine them, to then render both of them as useless? If I gave you 3 gallons of water and fertilizer would you throw them away? Unfortunately, our 'modern' sanitation system does exactly that. Every time we flush the toilet, we combine human excreta and 3 gallons of water to render them both useless. YES I am classifying human excreta not as waste but as a resource.
As volunteers in the field we come up against the cultural / custom battle of how human excreta is perceived all the time in rural communities. However, this battle would be x100000 times harder in the Western world, which can be for the most part considered to be fecophobic. Eastern cultures have been embracing humanure composting for centuries, as they see it as part of an ecological cycle. In fact, in South Korea humanure has been known to be sold on the black market!
Our current sanitation system does work from a public health standpoint. However, it is also consumes are amounts of resources and is completely dependent on the grid. In order for your excreta to move from your house or apartment to waste management facility requires a system that uses a lot of water and a lot of electricity. Humanure composting uses neither water or electricity. Could humanure composting be scaled up to someday make an impact on the global warming challenges we face?
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