Alternative Sanitary Systems - Basics and Technologies -

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1 Alternative Sanitary Systems - Basics and Technologies - M. Barjenbruch TU Berlin, Department of Urban Water Management Gustav-Meyer-Allee 25, D Berlin Phone: +49 / (0) 30 / ; Fax: +49 / (0) 30 / matthias.barjenbruch@tu-berlin.de

2 Ecological sanitation is a new paradigm in sanitation that recognises human excreta and water from households not as a waste but as resources that can be recovered, treated, where necessary, and safely used again. (gtz ecosan information material, 2007)

3 Global Water Volume Entire water: 1.38 billion km³ Cologne Salt water 97.4 % Fresh water 2.6 % (incl. Ice from oceans and glaciers) 36 million km³ Rome Hamburg Hannover 3.6 million km³ Only 0.3 % of the total water is available as drinking water

4 Definition of Water Shortage Available renewable fresh water supply > 1,700 m³/ head and year 1,000 till 1,700 m³/ head and year Possibly occasional or local water problems Periodic or regular water shortage <1,000 m³/ head and year Chronical water shortage Two thirds of the global available water is consumed by agriculture 60 % get lost by inefficient irrigation 30 to 40 % of the global food production depends on irrigation

5 World-wide use of water Agriculture Industry Domestic withdrawal consumption withdrawal consumption withdrawal consumption

6 World phosphorous resources Lifetime of phosphate reserves at different scenarios (parameter:yearly increase of phosphate consumption based on 7,000,000 t P 2 O 5 reserves) [%] most likely 20 2 % 3% 2,5% year Saskatchewan Interaktive 2002

7 Conventional discharge Systems History

8 500 v. Chr. Romans Cloaca-Maxima

9 Crap Tower Gold Bucket

10 Antecessor of sewer system Barrel-System Heidelberg [Otterpohl, Lange 1997]

11 The first flush toilette London obligatory introduction about 1860 Discharge in pits At first with overflow Later directly into the gutter feces, stench, hygienic nuisance moved from land property to streets Berlin % WC Berlin % WC

12 Elements of conventional urban drainage Separate System Combined System Infiltration SWO SWT WWTP [based on Gujer]

13 Future Objectives Climate change Demographic development Energy Ecological requirements Rainwater management Pharmaceutical Residual substances Advanced operation of all systems Situation of wastewater treatment in Germany Centrally degree of connection > 96% Length of sewer system (540,723 km; 6,57 m/e): combined sewer system: 239,086 km separate sewer system: for sewage: for stormwater: 187,264 km 114,373 km stormwater tanks: 45,457; 52.3 Mio. m³ 635 l/e municipal wastewater treatment plants: ca Purification capacity is excellent! Reconstruction needs: 17 % of municipal sewer need medium-term reconstruction Costs for medium-term reconstruction 45 billion Actual: 1,64 billion per year [2000] Private service connections!

14 Overview of conventional wastewater treatment systems Technical process Activated sludge (SBR, oxidation ditch, compact design, membran System Trickling filter or submerged bed, rotating disc Biofilter and submerged bed (aerated; anoxic) Moving bed; combined process Naturnahe Verfahren: Reed bed (vertical or horizontal flow) Natural aerated lagoon In arid regons reuse not reasonable! Technical aerated lagoon Combination of ponds and fixed bed

15 Luftbild Klärwerk Ruhleben Wastewater treatment plant: Berlin- Ruhleben Capacity: 247,500 m³/d; ~1,000,000 PE Constructed in 1963, several up-grading

16 Wastewater Discharge in Europe State 2007/2008 Source: WISE: nfigfile= WISE/config_uwwt2.xml

17 Situation of drinking water and sewage World wide Today nearly 1.2 billion people are without safe drinking water Demand: ~ m³/(person year) Biggest amount of water for production of food: omnivore : m 3 /year (80% vegetable + 20% meat) vegetarians: 600 m 3 /year Recyclable freshwater volume: max km³/year Present use km³/year Problem: growth of population; now 7 Billion 2.4 billion have no connection to wastewater treatment 90% of wastewater and excreta are poorly or not treated WHO: annually 5 million people die by water pollution Fight for water worldwide and will even reach europe Aim: efficient use fresh water- and other resources

18 Evaluation of the conventional system Advantages Secure hygienic conditions World-wide proofed technology High purification efficiency (removal of organic matters, nutrient ) High process stability Enlargement is possible Disadvantage High water consumption while using potable water as a transport medium End of Pipe Technology Leaks in the system resource destruction permanent losses of nutrients into the water bodies eutrophication None closed water and nutrient cycle High energy demand for wastewater treatment Polluted sludge as a waste product (disposal) The system is expensive

19 Process comparison conventional systems ecological sanitation systems current situation setting of development

20 Modern sanitation systems No technique, rather number of principles: 1. sustainable systems for wastewater treatment and sanitation 2. conservation of resources through lower water consumption substitution of chemical fertilisers minimisation of water pollution 3. integrated alternatives or addition to conventional treatment systems 4. promotion of recycling by safe, hygienic recovery and use of nutrients, organics, micro-pollutants, water and energy 5. minimisation of nutrient charge to surface water closing the loop

21 Component currents of wastewater yellow water: Urine with or without flush water brown water: faeces with flush water without urine grey water: black water: other domestic wastewater without urine and faeces faeces with flush water and urine

22 Comparison of pollution Unit Urine Feces Greywater Complete Source a FA 1 S FA 1 S FA 1 S FA 1 S A131 Volume l/(e d) 1,37 1,5 0,14 0, Solids g/(e d) COD g/(e d) 10 k.a. 52 k.a. 48 k.a. 110 k.a. 120 BOD 5 g/(e d) 5 k.a. 20 b k.a b k.a. 60 N g/(e d) 10,4 11,0 1,5 1,5 1 1,4 12,9 13,8 11 d P g/(e d) 1,0 1,0 0,5 0,5 0,5 0,5 2,0 2,0 1,8 a FA 1: DWA Book (2008), S: swedish reference number (Vinneras et al., 2006), reference from working paper ATV-DVWK A 131 (ATV-DVWK, 2000); A 118 for spec. Q b without toilet paper c Volume varies in dependence of flushing water consumption d measured as TKN c c 150 Flushwater saved by dry flow flush sanitation 6,000-20,000 l/(pe a)

23 Reuse of greywater Freshwater use in Germany 122 l/(p d) toilet; 30% personal hygiene; 38% washing; 13% garden; 3% other cleaning; 5% eat and drink; 4% dish washing; 7% Substitutable by recycled grey water FBR-wasserspiegel 2/06, modified

24 Greywater treatment Examples Toilettenspülung Reinigung Wäschewaschen.

25 Basic components of modern sanitation Sanitation System Collection Transport Recovery Treatment Components have to be reasonable combined

26 Summary of the compounds of modern Systems Classification into 6 basic systems Naming according the main characteristics and the number of flow systems Unified description of the systems facing at the path of flows Requirements of the water quality and the final products after treatment Purpose of application and remaining of the treated products

27 Blackwater 2-Material-Flow-System Minimum Water Quality Standard 1) Utilisation Place/ Source Material Flow and Transport Treatment Product rainwater service water toilet urinal pipe bio waste rainwater pipe blackwater pipe, vehicle phase separation storage C-elimination hygienisation recovery of nutrients phase separation red. micro-pollutants. stabilisation treated rainwater rainwater org. plant nutrients biogas treated wastewater vegetable biomass drinking water treated rainwater white /drinking water kitchen washing machine bathroom greywater pipe Low loaded greywater pipe C-elimination hygienisation P-elimination 2) phase separation stabilisation min.-org. plant nutrient treated wastewater service water white water sludge vegetable biomass 1) higher water quality possible for usage 2) makes sense only for kitchen wastewater ---- optional Source: [DWA, 2008]

28 Urine Diversion 3-Material-Flow-System Minimum Water Quality Standard 1) Utilisation Place/ Source Material Flow and Transport Treatment Product rainwater service water No Mixtoilet urinal pipe bio waste rainwater pipe brownwater pipe, vehicle, by hand phase separation storage hygienisation storage stabilisation treated rainwater rainwater org. plant nutrients biogas drinking water treated rainwater white /drinking water kitchen washing machine bathroom Yello water / urine pipe, vehicle greywater pipe low loaded greywater pipe hygienisation Nährstoffgew. phase separation red. micro-pollutants storage C-elimination hygienisation P-elimination 2) phase separation stabilisation treated wastewater vegetable biomass min.-org. Pfl.nährstoff treated wastewater service water white water sludge 1) higher water quality possible for usage 2) makes sense only for kitchen wastewater ---- optional vegetable biomass Source: [DWA, 2008]

29 Process comparison of different kinds of toilets kinds of toilets l/(person day) Advantages/Disadvantages flush toilet simple construction(+) high consumption of water(-) no reuse(-) vacuum toilet fully developed(+) high complexity(-) low consomption of flush water(+) no-mix-toilet low consomption of flush water(+) small-scale dilution(+) reuse of nutrients possible(+) waterless urinal increasing extention(+) increasing maitenance effort (-) compost toilet no flush water(+) high consumption of surface(-) higher maitenance effort(-) Based on Oldenburg 2005, modified

30 Systems for the catchment of black-, brown- and yellow water Examples Flushing toilets Vacuum toilets Composting toilet Separating toilets Urinals DWA Neuartige Sanitärsysteme 12/08

31 Correctly separated?

32 Requirements of separated flow treatment Recycling of nutrients production of storable nutrient for fertilizing Production of energy in Form von biogas Destruction of problematic micro-pollutants in the concentrated part Providing the hygienic demands Application of the treated wastewater for several purposes, e.g. irrigation, white water Many possible treatment processes can be applied: mechanical, physical-chemical and Biological treatment. A lot of processes are used and proofed already in conventional treatment

33 Treatment of the separated flows Example: Yellow water Only a few processes have been applied with practical experiences Storage Evaporation Struvite precipitation Elektrodialyse Ozonization Ammonia-Steam Stripping Experiences with different processes (specially biological) using similar input products (e.g. manure, sludge liquor ) Nitrification Anammox Denitrification Bio-P

34 Example: Treatment of yellow water Pilot-plant at the WTTP Köhlbrandhöft, HH Production of a NH 3 - solution Vacuum- Evaporation Quelle: Tettenborn, TU Hamburg Harburg

35 Example: Treatment of yellow water Results of evaporation Reduction of the volume: 20 l concentrate / m 3 urine -> factor for up-concentrating = 50x Product High concentrated nutrient solution P concentration: >99 % Remaining of N in the concentrate: ~ +90 % depending of feed-ph (favourable low) Energy demand: 200 Mj/m 3 No incrustration within the process Crystallsation in the stored concentrate

36 Examples of products

37 Treatment of yellow water Evaporation for concentrating nutrients Crystallization Stercorit: H(NH 4 )Na(PO 4 ) 4H 2 O Quelle: Tettenborn, TU Hamburg Harburg Analyse: Röntgen Diffraktometrie

38 Product Urine as fertiliser

39 Abstract and future prospects Modern sanitation systems are a good alternative to conventional wastewater treatment Urine as a fertiliser offers comparable substitute to mineral fertiliser By maintenance of sanitary standards good acceptance in Germany Application in developing or emerging countries is possible where no or only low level sewer systems are installed Applicable for industrialised countries only to sparsely populated areas without existing sewer systems or for new buildings? Challenges at the moment: Acceptance Hormons und pharmaceutical residues in urine Ecological fertiliser production from urine

40 thank you for your attention.