WASTE TO FERTILIZER
Josiane Nikiema, Olufunke Cofie and the IWMI RQ team
A dream to come true for Sub-Saharan Africa!
Contacts: [email protected] or [email protected]
OUTLINE
A. DAILY FERTILIZER POTENTIAL
FOR 200,000 PEOPLE100 MT of municipal solid wastes (MSW)
50 MT of inorg. wastes
50 MT of org. wastes 6-12 MT of biochar
15 MT of compost
0.6-1.2 ha of land
1.5 ha of land
100 m3 of fecal sludge (FS)
Land application
Composting 1.5 MT of compost
4 MT of co-compost
0.7 ha of Land
0.5 ha of land (maize)
1.3 ha of land (maize)
Biochar 1 MT of biochar 0.2 ha of land
EXAMPLE: CROP YIELDS AND IMPACT ON INCOME
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
Sheshegu Tuu-tengle Sheshegu Tuu-tengle
Yie
ld in
MT/
ha
Control
Farm 1
Farm 2
Farm 3
MAIZE
SORGHUM
($/ha) Users Non-users
Total fixed costs 191 137
Total variable costs 314 323
Revenues 919 606
Net Income 414 146
Location: Krobo
DAILY FERTILIZER POTENTIAL
FOR 200,000 PEOPLE270 m3 of urine
Direct land application
StruviteN:P:K:Mg of 6:29:0:10 Slow release fertilizer, suitable for plants or to
supplement other minerals
11 ha of Land
27 MT of excreta
Co-composting
Biochar
4-9 ha of Land
3-6 MT of biochar
13-26 MT of (co-)compost
0.3-0.6 ha of Land
80% of the nutrients needed to grow food for
the same population size
B. REUSE OPTIONS TESTED
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Crop type Non fertilized
Urine fertilized
Chemically fertilized
Country
Cabbage 19.5 32 31.0 Togo Cassava 45 60 60.0 Ivory
CoastCotton 0.18 0.35 0.38 MaliCorn 2.4 3.6 3.5 BeninEgg plant 2.8 16.0 17.1 Burkina
FasoLettuce 6.8 15.7 13.3 TogoOkra 1.7 2.3 2.6 Burkina
FasoSorghum 2.3 3.8 4.1 Burkina
FasoTomato 2.1 5.2 5.8 Burkina
FasoYam 4.0 8.0 6.0 Ivory
Coast
Crop Yields (Tons ha-1) for urine trials in different
West African countries. (CREPA, 2006)
2. ORGANIC SOLID WASTE
• Compared to Africa, Asia is more advanced
– E.g. Sri Lanka has 115 municipal solid waste (MSW) compost plants
– A2Z in Ludhiana (India) processes 900 MT/d of MSW through
– These plants are either fully publicly owned or managed under a PPP
Examples of Kenyan compost plants
Dudutech4 MT/d
EcoHHoldings 550 MT/d
Nawacom Coop. Society
28 MT/ d
Uga
nd
a; 6
0
MT/
d Ghana; 600 MT/d
And more large MSW compost plants…
Composting is common because it reducesvolumes of wastes and need for landfills
3. THE STORY IS QUITE DIFFERENT WITH EXCRETA
•
• Few exceptions processing some MT per day are:
Sanergy, KenyaSoil – Haiti
NGOs
Burkina Faso
Rwanda
KenyaSouth Africa
Etc.
Safisana compost Uses digested (sludge + org. wastes)
Loowatt, Madagascar
4. THE STORY IS WORSE WITH FECAL SLUDGE
FORTIFER (Wafo) In Ghana Senegal
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C. THERE IS OPPORTUNITY FOR SCALING UP
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NutrientsOrganic matter
Improvessoil quality
Improve crop yields
D. WHAT IS NEEDED FOR SUCCESSFUL SCALING-UP?
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ON THE GROUND, WE ALSO NEED TO:
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RECYCLING OF WASTE INTO FERTILIZER WILL THEN BECOME A FACT FOR
SUB-SAHARAN AFRICA
Compost
• Biochar
Direct land application
(Co-)compost
• Biochar
Direct application
• Struvite: MgNH4PO4.6H2O
Compost
• Dry soil conditioner
• Biochar
