1. Use of Dehydrates Faeces Use of Dehydrated Faeces 1 Gina S. Itchon, Xavier University

2. Use of Dehydrates Faeces Find this presentation and more on: www.sswm.info.www.sswm.info Copy it, adapt it, use it – but acknowledge the source! Copyright Included in the SSWM Toolbox are materials from various organisations and sources. Those materials are open source. Following the open- source concept for capacity building and non-profit use, copying and adapting is allowed provided proper acknowledgement of the source is made (see below). The publication of these materials in the SSWM Toolbox does not alter any existing copyrights. Material published in the SSWM Toolbox for the first time follows the same open-source concept, with all rights remaining with the original authors or producing organisations. To view an official copy of the the Creative Commons Attribution Works 3.0 Unported License we build upon, visit http://creativecommons.org/licenses/by/3.0. This agreement officially states that: http://creativecommons.org/licenses/by/3.0 You are free to: Share - to copy, distribute and transmit this document Remix - to adapt this document. We would appreciate receiving a copy of any changes that you have made to improve this document. Under the following conditions: Attribution: You must always give the original authors or publishing agencies credit for the document or picture you are using. Disclaimer The contents of the SSWM Toolbox reflect the opinions of the respective authors and not necessarily the official opinion of the funding or supporting partner organisations. Depending on the initial situations and respective local circumstances, there is no guarantee that single measures described in the toolbox will make the local water and sanitation system more sustainable. The main aim of the SSWM Toolbox is to be a reference tool to provide ideas for improving the local water and sanitation situation in a sustainable manner. Results depend largely on the respective situation and the implementation and combination of the measures described. An in-depth analysis of respective advantages and disadvantages and the suitability of the measure is necessary in every single case. We do not assume any responsibility for and make no warranty with respect to the results that may be obtained from the use of the information provided. Copyright & Disclaimer

3. Use of Dehydrates Faeces Find this presentation and more on: www.sswm.info.www.sswm.info 3 Contents 1.Concept 2.How it can optimize SSWM 3.Applicability 4.Advantages and disadvantages 5.References

4. Use of Dehydrates Faeces Find this presentation and more on: www.sswm.info.www.sswm.info 4 In a dehydration toilet, the excreta inside the processing vault are dried with the help of sun, natural evaporation and ventilation. After dehydration, faeces will reduce in volume by about 75%. Primary motivation for dehydrating the faeces is that dried faeces act as a hostile environment for pathogens and help to reduce the amount of pathogens in the faeces significantly over time. However, dry faeces may still contain pathogens. Oocysts, for example, can survive extreme environmental conditions and re-grow under favourable conditions. Secondary treatment (composting, vermicomposting) of dehydrated faeces should always be considered (if possible) as an additional barrier to inactivate pathogens (and here most importantly Ascaris). 1. Concept of the Use of Dehydrated Faeces in Agriculture

5. Use of Dehydrates Faeces Find this presentation and more on: www.sswm.info.www.sswm.info 5 1.How it can optimise SSWM Dry storage of the faeces recycles more organic matter and Nitrogen to the soil, but the organic matter is less stable. Dried faecal matter is a complete Phosphorus and Potassium fertiliser, which also contributes considerable amounts of Nitrogen. While the total amount of nutrients excreted with faeces is lower than with urine, the concentration of nutrients, and especially P and K, is high in faeces. P is particularly valuable for the plant in its early development and important for good root development. Faeces contain organic matter, which increases the water-holding and ion-buffering capacity of the soil, serves as food for the microorganisms and is important for improving soil structure.

6. Use of Dehydrates Faeces Find this presentation and more on: www.sswm.info.www.sswm.info 6 The handling and use of dried faeces may not be acceptable to some. However, because the dried faeces should be dry, crumbly, and odour free, the use of dehydrated faeces may be more acceptable than that of manure or sludge. Dried faeces are not as well treated or as useful as a soil amendment as composted faeces. However, they contain significant amounts of phosphorus, important in the early stage of plant growth and are useful for replenishing poor soils and for boosting the carbon content and thus the water-holding properties of soil with low-risk of pathogen transmission. Faeces should be incorporated into the soil and covered by a soil upper layer. Also the fertilisation of vegetables eaten raw should be avoided. 3. Applicability

7. Use of Dehydrates Faeces Find this presentation and more on: www.sswm.info.www.sswm.info 7 4. Advantages and Disadvantages Disadvantages: Labour intensive Requires that faeces are kept strictly dry Pathogens may exist in a dormant stage (oocysts) which may become infectious if moisture is added Can only partly replace fertiliser (N,P,K) (TILLEY et al. 2008) Advantages: Periodical incorporation can improve the structure and water-holding capacity of soil Simple technique for all users Low cost Low risk of pathogen transmission (when fully dried and properly handled) May encourage income generation (tree planting and fruit production) (TILLEY et al. 2008)

8. Use of Dehydrates Faeces Find this presentation and more on: www.sswm.info.www.sswm.info TILLEY, E., LÜTHI, C., MOREL, A., ZURBRÜGG, C., SCHERTENLEIB, R. (2008): Compendium of Sanitation Systems and Technologies. Switzerland: Swiss Federal Institute of Aquatic Science (EAWAG) & Water Supply and Sanitation Collaborative Council (WSSCC) WHO (2006): Guidelines for the Safe Use Wastewater, Excreta and Greywater, Volume 4: Excreta and Greywater Use in Agriculture. Geneva: World Health Organisation ECOSANRES. (2008): Guidelines on the Use of Urine and Faeces in Crop Production. (EcoSanRes Factsheets, No. 6) Stockholm, Sweden: Stockholm Environment Institute (SEI) 8 5. References

9. Use of Dehydrates Faeces 9 “Linking up Sustainable Sanitation, Water Management & Agriculture” SSWM is an initiative supported by: Compiled by: