M3: ecosan Systems and Technology Components M 3-1: ecosan Technologies to Close the Nutrient Loop J. Heeb J. Heeb J. Heeb J. Heeb Prof. Dr. Petter Jenssen, Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences Dr. Johannes Heeb, International Ecological Engineering Society & seecon international Dr. Ken Gnanakan, ACTS Bangalore, India Katharina Conradin, seecon gmbh © 2006 ACTS seecon Agriculture -Crafts - International gmbh Trades - Studies Credits Materials included in this CD-ROM comprise materials from various organisations. The materials complied on this CD are freely available at the internet, following the open-source concept for capacity building and non-profit use, provided proper acknowledgement of the source is made. The publication of these materials on this CD- ROM does not alter any existing copyrights. Material published on this CD for the first time follows the same open-source concept for capacity building and non-profit use, with all rights remaining with the original authors / producing organisations. Therefore the user should please always give credit in citations to the original author, source and copyright holder. We thank all individuals and institutions that have provided information for this CD, especially the German Agency for Technical Cooperation GTZ, Ecosanres, Ecosan Norway, the International Water and Sanitation Centre IRC, the Stockholm Environment Institute SEI, the World Health Organisation WHO, the Hesperian Foundation, the Swedish International Development Cooperation Agency SIDA, the Department of Water and Sanitation in Developing Countries SANDEC of the Swiss Federal Institute of Aquatic Science and Technology, Sanitation by Communities SANIMAS, the Stockholm International Water Institute SIWI, the Water Supply & Sanitation Collaborative Council WSSCC, the World Water Assessment Programme of the UNESCO, the Tear Fund, Wateraid, and all others that have contributed in some way to this curriculum. We apologize in advance if references are missing or incorrect, and welcome feedback if errors are detected. We encourage all feedback on the composition and content of this curriculum. Please direct it either to [email protected] or [email protected]. seecon K.K. Conradin Conradin Credits ecosan Curriculum - Credits Concept and ecosan expertise: Johannes Heeb, Petter D. Jenssen, Ken Gnanakan Compiling of Information: Katharina Conradin Layout: Katharina Conradin Photo Credits: Mostly Johannes Heeb & Katharina Conradin, otherwise as per credit. Text Credits: As per source indication. Financial support: Swiss Development Cooperation (SDC) How to obtain the curriculum material Free download of PDF tutorials: www.seecon.ch www.ecosan.no www.gtz.de/ecosan Order full curriculum CD: [email protected] € 50 (€ 10 Developing Countries) [email protected] Release: 1.0, March 2006, 1000 copies Feedback: Feedback regarding improvements, errors, experience of use etc. is welcome. Please notify the above email-addresses. Sources Copyright: Copyright of the individual sources lies with the authors or producing organizations. Copying is allowed as long as references are properly acknowledged. seecon K. Conradin How to use the tutorial When you come across these links, click directly on them. They will lead you either click here to additional documents, to the glossary of terms, or to definition pages. To go back, use the Adobe Acrobat Navigation Toolbar (shown below). Read more Buttons that link directly to pages with more detailed information Links Indicates Internet links and resources Further Indicates specific texts, files, or documents for further reading reading Case Shows a link to a case study that shows the connection between an abstract Study topic and the “real life situation” more closely. Sources are indicated in (99) brackets. You will find the full list of references at the (99) very end of the modules. Note & Information on Structure Note: This Module is mainly adapted from two different sources: • WHO (2005): Guidelines for the Safe Use of Wastewater, Greywater and Excreta. Chapter: Health Protection Measures (draft version) and • Chapter 4 of the Conceptual Design of decentralised Wastewater Treatment and Material Flow Management, Summer Course 2004 at the University of Hannover: “Sustainable Wastewater Management in Urban Areas” by P.D. Jenssen, J.M Greatorex & W.S. Warner, Contents 1. Introduction 2. Content Overview 3. Source Separated Wastewater Collection/Treatment Systems – Pit Toilets • Pit & VIP Latrines • Pour-Flush Latrines – Composting Toilets • Treatment: On-site/off-site dry composting • Treatment: Composting Toilets – Dry Composting Process • Further Information on Composting Toilets – Dehydration Toilets • Treatment: Dehydration Toilets • Further Information on Dehydration Toilets – Urine Diversion Toilets • Single-Flush Urine Diversion Toilets • Dual-Flush Urine Diversion Toilets • Waterless Urinals • Treatment: Urine Storage • Further Information on Urine Diversion Toilets – Watersaving Toilets J. Heeb Contents – Vacuum Toilets • Vacuum Sewer Systems – Vacuum Collection Tanks with Vacuum Pump – Vacuum generating and forwarding pumps – Vacuum on Demand (VOD) • Further Information on Vacuum-Toilets – Treatment: Treatment of blackwater fractions and organic waste • Treatment: Aerobic Treatment (Liquid Composting) • Treatment: Anaerobic Treatment (Biogas Production) • Treatment: Drying and Humification – Treatment: Further Treatment Methods • Vermicomposting • Wastewater-Fed Aquaculture 4. Handling and Transport of Excreta and Sludge 5. Logistics of Sustainable Systems in Urban Areas 6. Executive Summary J. Heeb Introduction Excreta contains most of the pathogens as well as the majority of the nutrients in wastewater (see Module 3-2). If excreta is treated separate and not mixed with the greywater several new possibilities for reuse of resources from wastewater arise. In order to collect excreta only, toilets that use no or very little water are the most feasible. Systems where the excreta is treated and handled separate from the greywater are termed source separating systems. Source separating systems either separate in two fractions the excreta (urine and faeces) and the greywater or some in three fractions urine, faeces and greywater (1). Energy Water (drinking Nutrient water) Filtration (membran e, sand) Fertilizer (N, P, K) Grey- Blackwa Ground- water ter water Soil Organic amend- recharge Biological Recrea- waste Aerobic ment tional Treatment treatment Anaerobic Watering water (compostin treatment garden g) (biogas) Graphic: Alsén & Jenssen (1) Content Overview This module will mainly concentrate on the nutrient and energy loop. First, this module explains suitable methods for collection of the recyclable resources in excreta (faeces and urine). The various options are explained on several slides, including a general system overview, management processes, risks, and maintenance, as well as advantages and possible drawbacks. Further Information is indicated where available. Additionally, you will find links to websites of product suppliers. The technological aspects of closing the water loop is exemplified in Module 3-2. A figure showing the different collection (i.e. toilet) options which facilitate the reuse and thus the closing of the nutrient and energy loop is shown on the next slide. Energy Water (drinking Nutrient water) Filtration (membran e, sand) Fertilizer (N, P, K) Grey- Blackw Ground- water ater water Soil Organic amend- recharge Recrea- Biological Aerobic waste ment Treatment treatment Anaerobic tional Watering water (composti treatment garden (biogas) Graphic: Alsén & ng) Jenssen (1) Source Separated Wastewater Collection/Treatment Systems P. Jenssen In order to be able to close the loop shown on the preceding slide, collection systems that facilitate the reuse are needed (first row). The different toilet options produce material of different composition regarding e.g. water content and hygiene therefore different treatment methods are required. What is inherent to all these systems is that they use as little water as possible, and thus keep the volumes that has to be treated small. As you can see the greywater is separated right from the beginning, and is not incorporated into the treatment processes of excreta. Greywater usually only has a very small grade of pollution and is much easier to sanitize than black- or yellowwater. The second row shows the treatment processes which are applied according to the respective collection systems, in order to make a hygienic product for reuse. Collection options are highlighted in yellow and Treatment/Hygienization systems in orange. Source Separated Wastewater Collection/Treatment Systems The toilet options used in the source separating systems range from pit toilets to modern urine diverting and vacuum toilet systems. There is a principle difference between the pit- and pour flush toilets (1) and the other options (2-4) in that the first utilize pits or soakaways in natural soils. These pose a threat to the groundwater quality and subsequently health, especially in areas where water from shallow wells is used. The pit toilets are originally constructed for disposal of excreta and not for reuse. A substantial amount of nutrients, nitrogen especially, is lost through percolation or evaporation. However, since excavating of full pit latrines provides possibilities of recycling phosphorus and organic matter in particular, they are still included in this module