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Course 2 Unit 4

Introduction to anaerobic treatment technologies

[Part C only ]

Part C – Examples and case studies (in this file)

Lecturer: Dr. Elisabeth v. Münche.vonmunch@unesco-ihe.org

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Course 2 Unit 4Part C: Examples and case studies

Course 2 Unit 4

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List of examples for Part C

Example 1: India public toilets (Navsarjan Trust, GTZ pilot project)

Example 2: China household and agricultural waste digesters (CAAE (Chinese Academy of Agricultural Engineering)

Example 3: Lesotho household biogas plants (NGO TED, now supported by BORDA, Germany)

Example 4: Durban household biogas plant, South Africa (pilot project)

Example 5: Rwanda prisons Example 6: Germany, Waldmichelbacher Hof

(restaurant and farm Example 7: Lübeck, Germany (residential area) Example 8: Blackwater treatment in Sneek, the

Netherlands

There are many, many more examples, world-wide!You may be able to send me project descriptions, files, powerpoint presentations from your own experiences?

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Example 1: India public toilets

The following slides were provided by Christine Werner (GTZ), who gave a presentation about ecosan in India at the Advanced Sanitation Conference in Aachen, Germany (12-13 March 2007)

Her complete presentation is provided under Assigned Reading (pdf file of the paper) and Extra Materials (powerpoint presentation in two parts)

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location:

Nani Devti, Ahmedabad District, Gujarat State, India

implementation period:

2005/2006

vocational training institute Dalit Shakti Kendra (DSK)

Navsarjan Trust ecosan pilot project – Dalit Shakti Kendra (DSK)

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proposed system for the DSK Campus

Navsarjan Trust ecosan pilot project

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dung greywater (pre-treated)

Biogas plant

urine storage

biogas

ornamental garden

source separating

toilet

vegetable gardensludge drying

beds

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ladies urinaltoilet block with biogas plant

Navsarjan Trust ecosan pilot project - DSK

UDD as „emergency toilets“

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Sketch map of the night-soil based biogas plant

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biogas plant

towards greywater garden for

reuse of water

towards greywater garden for reuse of water

towards sludge drying beds

infiltration/evapotranspiration of wash-water in flowerbed

2: inlet chamber toilet water

1: mixing chamber for buffalo dung

3: outlet chamber„pour-flush“ squatting pan with „P“-trap

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22 toilet cabins arranged in 2 semi-circles supplie a biogas reactor locatet in the center

(source: http://www.ruralsanitation.com/)

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Construction of the night-soil based biogas plant

inletchamber for toilet water

biogasreactor in the center of the building

almost finished toilet center Feb. 2007

beginnig of construction

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Example 2: China household and agricultural waste digesters

The slides for this example were provided by Heinz-Peter Mang (he is with CAAE (Chinese Academy of Agricultural Engineering))

I got them from him at the UNESCO-IHE Refresher Course in Nanjing, China (October 2005) – I have asked him for an update, but have not received an answer yet

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China: Northern “Four-in-One” Comprehensive utilization

Green housePig-pen, toiletkitchen

fertilizerbiogas

manure

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food

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Pig manure and toilet waste

biogas

Liquid

sludge Biogas digester

China: Southern “Pig-Biogas-Fruit” Comprehensive utilization

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China: Northwest “Five-Matches” Comprehensive utilization

Water heatercooking

lighting

Warm house

Biogas digester

Water storage

Sand

sedimentation

orchard

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Household biogas digester plants in China during 1973 – 2005 (total number, in 10,000)

0

200

400

600

800

1000

1200

1400

1600

1973

1975

1977

1979

1981

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

16,000,00016 million biogas plants

How many are there in your country?

Year 2005

1973

1999

1985

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Example 3: Lesotho household biogas plants

I got these slides from Mantopi Lebofa who works for the NGO TED, which is now also supported by BORDA, Germany

A more detailed presentation for this example is provided under Extra Materials

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Sketch of biodigester replacing a septic tank. Wastewater as well as kitchen and garden waste enter the digester and are broken down to biogas and fertile water.The advantages: No more emptying of septic tank. Reuse of all water in the garden. Less cost on cooking energy.

Methane producing organisms produce gas

Feeding material.

Gas taken to the house

Water flowing into the expansion canal

Root Treatment System

Storage for irrigation water – H20 could be pumped or irrigate gravitationally

Irrigation by gravity

Biogas system

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Radius

Fixed Dome Bio Digester, Size: z m3Gas storage capacity: xy m3

All measurements in cmNot to scale

pipes of 1m length

Principle of dry toilet connection and additional inlet

Gas Outlet Overflow

Ventilation Pipe

Manhole

Design details

Note: digester outlet at the bottom

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Example 4: Durban household biogas plant, South Africa (pilot project)

I took the photos on the following slide during the field trip organised as part of an international ecosan conference in Durban, South Africa (May 2005)

This installation was just a single pilot installed provided by an NGO (I can’t remember the name of the NGO)

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Household biogas plant in rural Durban, South Africa

Digester receives toilet water, greywater and collected manure from 2-3 cows

Storage and drying for digestate (used as fertiliser)

Left: Toilet (flush), connected to digesterMiddle: Digester with floating dome (biogas collection)Right: biogas pipe to house

Toilet & shower Kitchen

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Example 5: Rwanda prisons

The information in the following slides was taken from the paper by Butare and Kimaro (2002) – this paper is also provided under Extra Materials

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Biogas plant at Cyangugu Prison in Rwanda

Biogas plant treats toilet waste from prisoners by using fixed-dome anaerobic digesters

Generation of biogas was achieved to generate energy for cooking - savings in kitchen fuel is around 80%

Sustainable solution for the treatment of waste from 6,000 prisoners

Source: Butare and Kimaro (2002)

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Design details

Bioreactor is fed through two toilet-waste flows: one comes from 4,500 prisoners and the other from 1,500.

1 digester of V=150 m3 (divided in 2 shells to improve performance); a storage capacity of 28 m3; 2 holding tanks to further stabilize sludge.

Production of 75,000 CH4 L/day 30 m of gas line which feeds 4

stoves of 1200 L. Plant life time 30 years Effluent from biogas plant is

reused as fertilizer in crops inside prison (2 ha): bananas, coffee, soy, tomato, etc.

Bioreactor split into 2 shells

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Example 6: Germany, Waldmichelbacher Hof (restaurant and farm)

The following slides are from a presentation I gave at the Durban ecosan conference (May 2005)

More information: Separate presentation and paper under Extra Reading GTZ project datasheet: www.gtz.de/en/themen/umwelt-

infrastruktur/wasser/9399.htm

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Biogas plant with electricity generation at farm and restaurant in Germany

Description: Farm of 200 ha, with grazing

land and fodder crops 280 hornless cattle Restaurant with 250 seats

(“Waldmichelbacher Hof”) Slaughterhouse processing one

cattle per week Four families live and work

on/from the farm & restaurant

System components: Low flush toilets for all

buildings Manure collection, and mixing

channel under the cattle shed Heated, insulated and fully

mixed anaerobic digester with 280 m3 volume (40-44°C)

Anaerobic storage digester with 1500 m3

Two combined heat and power generator sets with 37 kW (electricity) and 74 kW (thermal energy / heat) each

This is an example to show that conventional flush toilets (non-UD) can also be used in an ecosan project!

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Key results

Annual savings in operating costs in 2004:

20,000 €/year for not needing to purchase fertiliser

23,400 €/year due to electricity produced on-site (more than 50% of the electricity demand covered)

Heat for all residential houses and restaurant, and hot water

5,300 €/year is the income from selling excess electricity to the grid*

Valuable liquid fertiliser (digested manure) produced

Sanitisation of sewage by mesophilic digestion and long retention times

Gas bladder of anaerobic digester no. 2 (not heated, not mixed; floating cover)

* New German legislation forces energy companies to buy back such green energy from decentralised production for a fair price

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Concept schematic of this closed-loop system

“Ecosan- Biogas Plant”

Fertiliser (“digested manure”)

Anaerobic digester (heated)

Biogas

Restaurant, shop,

distillery

Collection channel: Manure and ww storage tank effluent

Households

Barn and stable (in winter)

Cattle

Farmland Fodder

Horses

Slaughter- house

Cogeneration plant

Meat

Electricity exported to

the grid

ww storage

tank

E

H + E

H + E

M W

W

W W

W

OSW

E

BG

BG

F

F

DM

DM

W

H: heat, E: electricity, F: fodder, DM: digested manure, BG: biogas, W: waste(water)

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Design drawing

Floating cover

Gas withdrawal

Combined heat and power plant

Heat to house

electricity

Digester

Digested manure

Stable/ cattle shed

Storage vessel

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Example 7: Lübeck, Germany (residential area)

The information on the following slides was taken from the GTZ project datasheet on this project:

http://www.gtz.de/de/dokumente/en-ecosan-pds-004-germany-luebeck-flintenbreite-2005.pdf

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Housing estate with biogas plant in Lübeck-Flintenbreite

(slide 1 of 2)

Integrated sanitation system using vacuum toilets and biogas plant = production of energy + saving of water

Foreseen for a community of 350 inhabitants

Area of 3.5 ha which was not connected to central sewerage

Separate treatment of grey, black and storm water

Digested anaerobic sludge is reused in agriculture

Biogas plant

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Process schematic(slide 2 of 2)

vacuum toilet

Biogas plant

Kitchen, shower

Greywater

(56 L/cap/d)

Effluent

Biogas

Kitchen residue

Blackwater

(4.8 L/cap/d)

wetlands

Effluent

Storm water

infiltration

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Example 8: Blackwater treatment in Sneek, The Netherlands

The next slide is from myself and the remaining slides for this examples are from Brendo Meulman, Landustrie, the project leader (provided in Sept 2007)

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Neighbourhood “UASB-septic tank” for blackwater in Sneek, The Netherlands

• The “UASB-septic tank” is located in this garage, together with storage tanks and other experimental process units• It treats the blackwater from 80 persons (400 – 500 L/d; 5.6 L/cap/d; 1 L per flush)• Digester is heated to 20 or 30°C with hot water generated with biogas

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General view of the housing area

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How to get a concentrated organic fraction?

Vacuum toilets are used, they flush with 1L water and 100L of air. Reduction of 36 L/cap/d water, is 25% of total water consumption

Vacuum toilet Vacuum station (pump)

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References Butare, A and Kimaro, A (2002) Anaerobic technology for toilet

wastes management: the case study of the Cyangugu pilot project, World Transactions on Engineering and Technology Education, Vol.1, No.1. http://www.eng.monash.edu.au/uicee/worldtransactions/WorldTransAbstractsVol1No1/Microsoft%20Word%20-%2032_Butare.pdf *

Heeb, J., Jenssen, P., Gnanakan, K. & K. Conradin (2007): ecosan curriculum 2.0. In cooperation with: Norwegian University of Life Sciences, ACTS Bangalore, Swiss Agency for Development and Cooperation, German Agency for Technical Cooperation and the International Ecological Engineering Society. Partially available from www.seecon.ch and http://www2.gtz.de/dokumente/oe44/ecosan/cb/en-m23-ecosan-human-dignity-lecture-2006.ppt

Tchobanoglous, G., Burton, F.L., Stensel, H.D. (2003) Wastewater Engineering, Treatment and Reuse, Metcalf & Eddy, Inc., McGraw-Hill, 4th edition. This is a good book on conventional wastewater treatment

Zhang Wudi et al. (2001): Comprehensive utilization of human and animal wastes. Proceedings of the First International Conference on Ecological Sanitation in Nanning 2001,EcoSanRes, China

Course 2 Unit 4

* Also under Extra Materials on the I-LE

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Other organisations and websites for biogas plants

BORDA (Bremen Overseas Research and Development Association): www.borda-net.org - extensive experience with decentralised anaerobic wastewater treatment (mostly without source separation), e.g. Household biogas plants all over the world. See also their website to view the presentations at recent symposium “Business Unusual” Nov. 2006

Biogas for Better Life, An African Initiative  (www.biogasafrica.org) – New initiative from May 2007, see next slide for more information

Agency for renewable resources: www.fnr.de (Fachagentur für nachwachsende Rohstoffe; in German and English)

Fachverband Biogas: www.biogas.org (in German only)

Internationales Biogas und Biomasse Kompetenzzentrum (IBBK) (http://www.biogas-zentrum.de/ibbk/) – in German only

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Some more information about the Biogas for Better Life Initiative

Pan African Biogas Initiative Launched : 31 May 2007

A large-scale biogas initiative has been launched to bring renewable energy to 20 million households in some 25 African countries. The initiative was approved at a conference entitled 'Biogas for Better Life: An African Initiative', held in Nairobi, Kenya on 22 May 2007. The initiative is being supported by a consortium consisting of African countries (including Benin, Ethiopia, Ghana, Kenya, Mali, Nigeria, Rwanda, Senegal and South Africa), implementing agencies, local NGOs and donors (including Finland, Germany, the Netherlands, Norway and the Shell Foundation).

Dutch partners in the initiative are the Ministry of Foreign Affairs and development organisations SNV and Hivos.

The first national biogas programme – in Rwanda –has already begun. Similar programmes in Ethiopia and Uganda will begin later this year. These national programmes aim to construct the initiative’s first 50,000 biogas plants. Biogas programmes are already operational in various parts of the world. SNV has worked on several successful programmes in Asia, especially in Nepal and Vietnam.

A simple biogas plant can be operated by any family with at least two cows or four pigs. The family toilet can also often be connected to it. Such a plant will generate enough gas to power a stove and a lamp.A biogas plant costs from 300 to 400 euros (although in Africa it will initially cost more). But the expense can be recouped within a few years through savings on firewood. And the waste product can still be used as manure.