NationMaster - Encyclopedia: Ecological sanitation

Ecological sanitation, also known as ecosan, is a modern alternative to conventional sanitation techniques. The objectives are to offer economically and ecologically sustainable and culturally acceptable systems that aim to close the natural nutrient and water cycle. Unlike most traditional sanitation methods, ecological sanitation processes human waste to recover nutrients that would otherwise be discarded. E. Coli bacteria under magnification Sanitation is the hygienic disposal or recycling of waste, as well as the policy and practice of protecting health through hygienic measures. ... The movement of water around, over, and through the Earth is called the water cycle. ... Human waste is a waste type usually used to refer to byproducts of digestion, such as faeces and urine. ... Nutrients and the body A nutrient is any element or compound necessary for or contributing to an organisms metabolism, growth, or other functioning. ...

Introduction to ecological sanitation

Ecological sanitation (ecosan) offers a new philosophy of dealing with what is presently regarded as waste and wastewater. Ecosan is based on the systematic implementation of reuse and recycling of nutrients and water as a hygienically safe, closed-loop and holistic alternative to conventional sanitation solutions. Ecosan systems enable the recovery of nutrients from human faeces and urine for the benefit of agriculture, thus helping to preserve soil fertility, assure food security for future generations, minimize water pollution and recover bioenergy. They ensure that water is used economically and is recycled in a safe way to the greatest possible extent for purposes such as irrigation or groundwater recharge. ^[1] Waste inside a wheelie bin Waste in a bin bag Waste, rubbish, trash, garbage, or junk is unwanted or undesired material. ... Wastewater is any water that has been adversely affected in quality by anthropogenic influence. ... The international recycling symbol. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... A Proportional-Integral-Derivative controller is a standard feedback loop component in industrial control applications. ... Rabbit feces are usually 0. ... This article is about the urine of animals generally. ... Fertile soil is soil that can support abundant plant life, in particular the term is used to describe agricultural and garden soil. ... Subsistence farmers with a Treadle Pump. ... Raw sewage and industrial waste flows into the U.S. from Mexico as the New River passes from Mexicali, Baja California to Calexico, California Water pollution is a large set of adverse effects upon water bodies such as lakes, rivers, oceans, and groundwater caused by human activities. ... Bioenergy is renewable energy made available from materials derived from biological sources. ... Irrigation is the artificial application of water to the soil usually for assisting in growing crops. ... Groundwater recharge is the practice of directing water - often rainwater, but sometimes reclaimed water - into groundwater aquifers. ...

According to the 10 Recommendations for Action, published at the 2^nd international ecosan symposium 2003 in Lübeck, Germany, the main objectives of ecological sanitation are ^[2]:

It has been suggested that this article or section be merged into Water quality. ... Surface water is water on the ground or in a stream, river, lake, sea or ocean; as opposed to groundwater. ... Groundwater is any water found below the land surface. ... Water resources are sources of water that are useful or potentially useful to humans. ...

History of reuse-oriented sanitation approaches

In a very broad sense the recovery and use of urine and faeces has been practiced over millennia by almost all cultures. The uses were not limited to agricultural production (although for modern application this may be of most relevance), like the Romans who were well aware of the disinfecting attributes of urine and also used it for washing clothing. Roman or Romans has several meanings, primarily related to the Roman citizens, but also applicable to typography, math, and a commune. ... Disinfectant redirects here. ...

The most widely known example of the diligent collection and use of human excreta in agriculture is China. It is reported that the Chinese were aware of the benefits of using excreta in crop production before 500 B.C., enabling them to sustain more people at a higher density than any other system of agriculture. The value of “night soil” as a fertiliser was clearly recognised with well developed systems in place to enable the collection of excreta from cities and its transportation to fields. Excreta is a generic term used to refer to any masses or fluids excreted as part of the digestive system of a living organism, usually that of humans. ... Look up crop in Wiktionary, the free dictionary. ... Night soil is a term most often used to describe the practice of using untreated human waste as fertilizer. ... Fertilizers are chemicals given to plants with the intention of promoting growth; they are usually applied either via the soil or by foliar spraying. ...

Elaborate systems were developed in urban centres of Yemen enabling the separation of urine and excreta even in multi-storey buildings. Faeces were collected from toilets via vertical drop shafts, while urine did not enter the shaft but passed instead along a channel leading through the wall to the outside where it evaporated. Here, faeces were not used in agriculture but were dried and burnt as fuel. For other uses, see Toilet (disambiguation). ... For other uses, see Fuel (disambiguation). ...

In Mexico and Peru, both the great Aztec and Inca cultures collected human excreta for agricultural use. In Peru, the Incas had a high regard for excreta as a fertiliser, which was stored, dried and pulverised to be utilized when planting maize. Aztec is a term used to refer to certain ethnic groups of central Mexico, particularly those groups who spoke the Nahuatl language and who achieved political and military dominance over large parts of Mesoamerica in the 14th, 15th and 16th centuries, a period referred to as the Late post-Classic... For other meanings of Inca, see Inca (disambiguation). ... This article is about the maize plant. ...

In the Middle Ages, the use of excreta and greywater was the norm. European cities were rapidly urbanising and sanitation was becoming an increasingly serious problem, whilst at the same time the cities themselves were becoming an increasingly important source of agricultural nutrients. The practice of using the nutrients in excreta and wastewater for agriculture therefore continued in Europe into the middle of the 19th Century. Farmers, recognising the value of excreta, were eager to get these fertilisers to increase production and urban sanitation benefited. ^[3] The Middle Ages formed the middle period in a traditional schematic division of European history into three ages: the classical civilization of Antiquity, the Middle Ages, and modern times, beginning with the Renaissance. ... Greywater, sometimes spelled graywater, grey water or gray water and also known as sullage, is non-industrial wastewater generated from domestic processes such as washing dishes, laundry and bathing. ... For other uses, see Europe (disambiguation). ... Farmer spreading grasshopper bait in his alfalfa field. ...

The increasing number of research and demonstration projects for excreta reuse carried out in Sweden from the 1980s to the early 21st century aimed at developing hygienically safe closed loop sanitation systems. Similar lines of research began elsewhere, for example in Zimbabwe, in the Netherlands, Norway and Germany. These closed-loop sanitation systems became popular under the name “ecosan”, “dewats”, “desar”, and other abbreviations. They placed their emphasis on the hygenisation of the contaminated flow streams, and shifted the concept from waste disposal to resource conservation and safe reuse. ^[4] This article is about the concept. ... Reuse is using an item more than once. ... Waste management is literally the process of managing waste materials (normally those produced as a result of human activities). ...

Concepts of ecological sanitation

Ecological sanitation (ecosan) is a new holistic paradigm in sanitation, which is based on an overall view of material flows as part of an ecologically and economically sustainable wastewater management system tailored to the needs of the users and to the respective local conditions. It does not favour a specific sanitation technology, but is rather a new philosophy in handling substances that have so far been seen simply as wastewater and water-carried waste for disposal. ^[5] For other uses, see Paradigm (disambiguation). ...

According to Esrey et al. (2003) ^[6] cological sanitation can be defined as a system that:

Ecosan offers a flexible framework, where centralised elements can be combined with decentralised ones, waterborne with dry sanitation, high-tech with low-tech, etc. By considering a much larger range of options, optimal and economic solutions can be developed for each particular situation. ^[7] This article is about the medical term. ... This article does not cite any references or sources. ... High tech refers to technology that is at the cutting-edgeâ€”the most advanced technology currently available. ... The term low-technology is a description of those crafts and tools whose inception (typically) predates the Industrial Revolution. ...

The figure below shows the potential positve impacts of an optimal ecosan approach:

A pathogen or infectious agent is a biological agent that causes disease or illness to its host. ...

Technologies of ecosan systems

It is not easy to determine ecosan systems as ecological sanitation is not just one specific technology, but a new approach based on an ecosystem-oriented view of material flows.

The following diagram gives an overview of the different collection, treatment and reuse possibilities of the five flow streams considered in ecological sanitation systems:

Further information on ecosan technologies can be found in "Ecological Sanitation" by Winblad et. al. ^[8], in "Toilets that make compost" by Peter Morgan ^[9] or in the gtz-ecosan technical data sheets ^[10], among other relevant literature.

Project examples

Examples for ecosan projects can be found among others in the collection of project data sheets of gtz ecosan ^[11] or on the Enhanced Global Map of ecosan activities by EcoSanRes ^[12]. In the following some examples are given that underline the diversity of ecosan projects:

Gunaxi province, China - large-scale project of urine diverting dehydration toilets The dissemination programme of ecological dry toilets for Guanxi province, one of the poorest provinces in China, started in 1997 with support of UNICEF, SIDA and the Red Cross and has been expanded to 17 provinces until the year 2003. By this year, the scale of the project had increased to approximately 685,000 toilet units – today more than one million double vault urine diversion dehydration toilets (UDDTs) are installed in rural areas of China. In UDDTs, urine and faeces are collected separately: The urine is collected in the front and lead by a plastic pipe to a storage canister from where it can be used as a fertilizer in agriculture, the faeces fall at the back in one of two ventilated storage chambers and are covered with ash for better dehydration. After about one year of storage the dried material can be removed and used as a soil conditioner in agriculture. ^[13] Hsinchu County (新竹縣, pinyin: Xīnzhú Xiàn) is a county in northwestern Taiwan. ... UNICEF Logo The United Nations Childrens Fund or UNICEF (Arabic: ; French: ; Spanish: ) was established by the United Nations General Assembly on December 11, 1946. ... The Anarchist Black Cross was originally called the Anarchist Red Cross. The band Redd Kross was originally called Red Cross. This article needs to be cleaned up to conform to a higher standard of quality. ...

KfW, Frankfurt, Germany - vacuum toilets + greywater treatment The sanitation concept of the modern office building “Ostarkarde” of the KfW Bankengruppe in Frankfurt is based on a separate excreta and greywater collection. While urine and faeces are collected via vacuum toilets and a vacuum sewerage using much less water for flushing, the greywater from hand washing and kitchen is collected and treated separately in a compact activated sludge reactor combined with membrane filtration. The treated greywater is then reused for toilet flushing and cleaning water. The amount of greywater can be reduced by 76% by this cost-efficient system which could be one of the prior choices for sanitation systems of newly constructed office buildings. ^[14] Kreditanstalt für Wiederaufbau (KfW) is a development bank based in Frankfurt, Germany. ... Look up Vacuum in Wiktionary, the free dictionary. ... Schoolchildren washing their hands before eating lunch. ... Activated sludge is a process in sewage treatment in which air or oxygen is forced into sewage liquor to develop a biological floc which reduces the organic content of the sewage. ... It has been suggested that Net flux be merged into this article or section. ... Look up filtration in Wiktionary, the free dictionary. ...

References

^ [Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) and International Water Association (IWA) (2003): “Greeting and opening session; Ecosan – a realistic tool to achieve the Millenium Development Goals”]
^ [Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) and International Water Association (IWA) (2003): “10 Recommendations for Action from the Luebeck Symposium on ecological sanitation”]
^ [Bracken et al. (2006): “The Road Not Taken: How traditional excreta and greywater management may point the way to a sustainable future”]
^ [UNESCO/IHP and Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH (2006): “Capacity building for ecological sanitation – Concepts for ecologically sustainable sanitation in formal and continuing education”]
^ [Werner, Christine (2006): “Closing the loop through ecological sanitation”]
^ [Esrey, Steven A., Andersson, Ingvar et al. (2003): ”Closing the Loop – Ecological sanitation for food security”]
^ [Jenssen, Petter D., Heeb, Johannes et al. (2004): “Ecological sanitation and reuse of wastewater. ecosan. A thinkpiece on ecological sanitation”]
^ [Winblad, Uno and Simpson-Hébert, Mayling. (2004). Ecological Sanitation - revised and enlarged edition]
^ [Morgan, Peter. (2007). Toilets that make compost. Low-cost, sanitary toilets that produce valuable compost for crops in an African context]
^ [GTZ technical data sheets. http://www.gtz.de/en/themen/umwelt-infrastruktur/wasser/9397.htm]
^ [GTZ project data sheets. http://www.gtz.de/en/themen/umwelt-infrastruktur/wasser/9399.htm]
^ [EcoSanRes Global Map of ecosan activities. http://www.ecosanres.org/]
^ [GTZ. (2005). Urine diversion dry toilets dissemination programme Guanxi province, China. Ecosan project data sheet #005. Available at: http://www.gtz.de/en/themen/umwelt-infrastruktur/wasser/9399.htm]
^ [GTZ. (2005). Vacuum sewerage and greywater recycling, office building "Ostarkade" of the KfW Bankengruppe Frankfurt am Main, Germany. Ecosan project data sheet #001. Available at: http://www.gtz.de/en/themen/umwelt-infrastruktur/wasser/9399.htm]

Contents