The Future of Sanitation a return to circular systems

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1 The Future of Sanitation a return to circular systems Presentation at Håkan Jönsson Symposium, SLU October 25, 2017

2 Was the strong link between the water and sanitation sectors in the 20 th century a brief detour in human history? Most common What will come next? agriculture + sanitation water + sanitation agriculture + sanitation All rural/subsistance Mostly urban All urban Jan-Olof Drangert, Linköping University, Sweden

3 Actual reuse of nutrients for urban agriculture & food security (in Swedish towns ) Proportion nutrients being reused 100% 50% Glass, tins, ceramics Heavy metals waste pits + urine diversion +WC only WC +WWTP stop Jan-Olof Drangert, Linköping University, Sweden

4 vent pipe faeces Urine-diverting toilet in the 1860s and sanitation footprints 1910 urine collector 60km Stockholm urine bowl urine funnel Jan-Olof Drangert, Linköping University, Sweden

5 Jan-Olof Drangert, Linköping University, Sweden Piped or pipe-less cities for waste transport Period Solid streetwaste Solid waste kitchen- faeces urine Earth pits for all household waste and content emptied in garden or on nearby farm Disposed of in streets or in yard Container for solid waste collection Solid waste incinerated Some garbage sorted Sorting of garbage and reuse Latrine buckets of metal Excreta Wastewater Disposed of in streets or in yard Urine and greywater to a septic tank/waste pit or straight to water body Black (WC)- and greywater in pipe to water body without any treatment Wastewater treatment plants being built Some sludge applied on farmland Scenario 1: grinder for organic kitchen waste, increased mixing of waste and incineration of the sludge Scenario 2: garbage sorted in more fractions, which are treated separately and used in production of new products

6 Nutrient flows originating from households To compost 14 % P, 1 Biowaste Illegal dumping 7 % P, 10 % N HH Greywater 20 % P, Excreta 59 % P, 70 % N To air: 1 % P, 40 % N Septage 10 % P 10 % N Effluent 48 % P, 20 % N Illegal dumping 4 % P, Compost 20 % P, 20 % N To air: 1 % P, 1 To farm: 19 % P, Jan-Olof Drangert, Vatema

7 Nutrient flows originating from households Compost 19 % P, 20 % N Biowaste Illegal dumping 2 % P, HH Greywater 20 % P, Effluent 2 % P, 3 % N WWTP 20 % P Faeces 19 % P, 7 % N Urine 40 % P, 63 % N Sludge 18 % P 2 % N To air: 1 % P, 1 % N Dewater 15 % P 4 % N Effluent 3 % P, 2 % N Uncontrolled dumping 1 % P, 2 % N To forest: 18 % P 2 % N To air: 1 % P, 8 % N Compost 33 % P, 22 % N To farm: 40 % P. 63 % N To farm: 32 % P, 14 % N Jan-Olof Drangert, Vatema

8 Strategies for sanitation improvements Principle: Organic other solid waste Stormwater sewage Industrial household wastewater Black toilet water greywater or Faeces urine Jan-Olof Drangert, Linköping University, Sweden

9 Solid and liquid waste hierarchy: reduce, reuse and recycle P in the EU

10 Sustainable Sanitation for the 21 st Century A Sourcebook and a set of powerpoints support material for training of professionals in the sanitation and water sector Available for free at

11 ON/ OFF A holistic sanitation selection algorithm Is there an aim/policy of reuse or sustainability? Make alliances and find your way around Is wastewater quality a major concern/problem? Is wastewater pollution caused by excreta? Is household organic waste sorted? Compost and use nutrients on site Energy for household Jan-Olof Drangert, Linköping University, Sweden Is there eugh space and infiltration/evaporation capacity on site? Can the pollution be eliminated through source control? Is diversion of urine an affordable option? Can faecal matter be composted on site? Can urine be stored and used on site? Is biogas reactor feasible on site? Collection & reuse off site greywater Fertilise garden On-site reuse of safe wastewater Is treatment on site effective & affordable? Is settled sewerage affordable? Is biological treatment affordable & safe? Swale/fish pond Is simplified sewerage affordable? Is swale/open ditch possible? Is infiltration or other reuse safe? problem Reuse of polished water