Decentralized Sanitation for Rural Areas

Univ. Prof. Dr.-Ing. Ralf OtterpohlDirector

Institute of Wastewater Managementand Water Protection

Chair, Specialist GroupResources oriented Sanitation

Water misused: Brussels, 2004

What type of system? (cost-comparison!!)

On-Site?

Community plant?

Connect?Connect?

On-Site is now accepted as long term solution in Germany

What type of system? (cost-comparison!!)

On-Site?

Community plant?

Connect?Connect?

Bad examples from Eastern Germany

Why: Very good business,bribery, lack of knowledge

Real costs up to 50€/m³

Brandenburg 2008:Police enforces usage of sewers despite reusesystem

High quality treatment: MBR

Busse, Germany

Avoiding health risks?

On-Site sanitation conventional:• Septic tank, often no further treatment: nitrate and

pathogens can pollute groundwaterSludge is unusable, trucked away

• Further treatment: very rarely nutrient removal, still nitrate in groundwater, still pathogens (but less)

Vo

lum

el/(

P*y

ea

r)

Urine ~ 500

Feaces~ 50

(option: add biowaste)

Greywater 25.000 -100.000

Yearly Loadskg/(P*year)

Flushwatercan be saved6.000 - 25.000

Vo

lum

el/(

P*y

ea

r)

Urine ~ 500

Feaces~ 50

(option: add biowaste)

Greywater 25.000 -100.000

N ~ 4-5 ~ 3 % ~ 87 % ~ 10 %

~ 34 %K ~ 1,8 ~ 54 % ~ 12 %

P ~ 0,75 ~50 % ~ 40 %~ 10 %

COD ~ 30 ~ 41 % ~ 12 % ~ 47 %

Reuse / Water Cycle

Treatment

Fertiliser

Biogas-PlantComposting

Treatment

Yearly Loadskg/(P*year)

Soil-Conditioner

S, Ca, Mg and traceelements

Geigy, Wiss. Tabellen, Basel 1981, Vol. 1, LARSEN and GUJER 1996, FITSCHEN and HAHN 1998

Flushwatercan be saved6.000 - 25.000

Vo

lum

el/(

P*y

ea

r)Greywater

25.000 -100.000

N ~ 4-5 ~ 3 % ~ 87 % ~ 10 %

~ 34 %K ~ 1,8 ~ 54 % ~ 12 %

P ~ 0,75 ~50 % ~ 40 %~ 10 %

COD ~ 30 ~ 41 % ~ 12 % ~ 47 %MOST

PATHOGENS!

Yearly Loadskg/(P*year)

DANGER!do not mix

Feaces~ 50

Ecosan principles:Containment,

sanitisation, reuse(Ecosan is not a technology but following

these principles)

Full REUSEZERO Emissions…

Toilets and resulting DilutionType of Toilet Daily Flow per P. Pro and Con'sFlushingtoilet+widely accepted-waste of water-high dilutionVacuum-toilet+low water demand+well developed (ships)-high-tec / expensiveSeparatingtoilet+little water / little dilution+simple fertiliser reuse-little experienceWaterlessUrinal+no water / no dilution-maintenance requiredComposting-toilet+no water needed-high space demand-maintenance needed

Desiccation toilet++ Desiccation for hot climates

Low/Non-diluting toilets are the key for new sanitation concepts

Vacuum-Biogas-System:32 houses in Sneek, The Netherlands

Sorting-Toilet(Gustavsberg, Sweden)

Waterless Urinal(Keramag)

Pilot Project “Lambertsmühle”

Initiative and Finance:• Wupperverband and Verein LambertsmühleDevelopment of the Sanitation Concept• Otterwasser GmbH, Lübeck

Scientific consultation • TUHH Inst. of Wastewater ManagementElements of the Sanitation Concept:

• Urine-sorting Toilets and waterless Urinals• Storage Tank for Yellow Water• Pre-Composting Tank (2 chambers, Filter Bags)• Constructed Wetland for filtered Grey- and Brownwater

Sawdust or ashes are used to ‚flush‘squat-urine-

diversion-toilet

WECF: Women in Europe for a Common

Future (Holland)in co-operation with

TUHHwww.wecf.org

Ecosan Toilets, Romania (TUHH / WECF)

New school toilet, Ukraine (TUHH/WECF)

Custom-made Urine-tank (GRP)Custom-made Urine-tank (GRP)

Sevastopol-Workshop

Sevastopol-Workshop

Vo

lum

el/(

P*y

ea

r)Greywater

25.000 -100.000

N ~ 4-5 ~ 3 % ~ 87 % ~ 10 %

~ 34 %K ~ 1,8 ~ 54 % ~ 12 %

P ~ 0,75 ~50 % ~ 40 %~ 10 %

COD ~ 30 ~ 41 % ~ 12 % ~ 47 %MOST

PATHOGENS!

Yearly Loadskg/(P*year)

DANGER!do not mix

Feaces~ 50

Additional remarks• Development of innovative sanitation can go

together with local employment (production and operation)

• Simple urine diversion solves the problem of nitrogen emissions to water

• - but proper reuse is required

• Ecosan is maturing very fast, better products

• Greywater treatment can be combined with reuse

• Operation and maintenance are crucial issues that have to be assured

Conclusions

• On-Site sanitation is a proven, cost efficient and accepted solution

• Conventional systems are usually not resouce efficient and still spread nitrogen and pathogens

• Innovative systems are proven, reuse and low emissions go together with local employment

• Awareness campaigns on all levels are crucial

• Cheapest solution is often dry UD-toilets with added value and water efficiency