Josiane Nikiema, O Cofie, Pay Drechsel, R Impraim www.iwmi.org/Topics/Resource_Recovery_and_Reuse/index.aspx

1. FORTIFIED EXCRETA PELLETS FOR
AGRICULTURE
An update on research in Ghana
Josiane Nikiema, O Cofie, R Impraim, Pay Drechsel
Researcher – Environmental Sciences
West Africa Office – Accra, Ghana
Phone: (+233) 302 784 753/4
Skype: Josiane.nikiema
Fax: (+233) 302 784 752
Email: J.Nikiema@cgiar.org
Water for a food-secure world
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2. What we did so far
Ghana: 24.2 Million inhabitants, 95% depending on on-site
sanitation
Research in Ghana from 2000 to date
– Direct application of urine to soil
– Land application of FS
– Extended storage of FS
– Composting of Feces
– Co-composting of FS and solid waste
– Fortification (blending) of fecal compost
– Agronomic trials (crop and soil response, safety)
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3. Drying
Aim of the BMGF project
Composting/Irradiation
• Pelletization of FS based materials to
increase the marketability Grinding
– Increase general acceptability
Enrichment
– Increase the ease of handling and
placement
Pelletization
– Improve fertilizer use efficiency
Drying
• Key partners: 3 Universities,
1 Municipality, 1 Research Institute Sieving
Use - Agronomic trials
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4. Drying beds
Step 1. Drying step
Over 2 tonnes DFS produced
• Size: 240 m2 per drying bed
• 18 tankers needed
– 6 public latrines; Average
retention time at source:
2.4 weeks
DFS
– 12 Septic tanks: Average
retention time at source:
1.6 years

5. Step 2. Composting
FS + Sawdust or market
waste
Three different formulations
70 1400
Total amount of added water (L)
60 1200
Temperature (˚C)
50 1000
40 800
30 600 First stage
20 Temperature 400
10 Water requirement 200
0 0
0 15 30 45 60 75 90
Time (days)
Temperature change and water added during
composting of DFS Final stage

6. Step 3. Grinding
• Capacity: 450 kg/hr
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7. Step 4. Enrichment
• Enrichment: allows to align the composition to the needs for
different crops and soil
• Also contributes to further sanitization
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8. Step 5. Pelletization
• Capacity: 100 kg/hr
• Water and binders are also added
– 2 binders tested:
Clay, Irradiated/pre-gelatinized
starch

9. Critical factors for pelletization
• Moisture content
• Minimizing loss (fine materials generated during production)
• Pellet stability
• Bulk density: at least 20-50 % reduction
• Disintegration time (nutrient availability timing)
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10. Disintegration time (hours)
140
120 PG IR
Time (Hours)
100
80
60 I-DFS
40
t = 0 hr t = 46 hr, 0%
20
EC-DFS binder
0
0% 1% 3% 5%
Binder concentration
Binder good for transport stability
And also for breakdown in soil
t = 46 hr, 5% pre- t = 46 hr, 5%
gelatinized starch irradiated starch

11. On-going greenhouse/field experiments
Tested products
A. EC-SDFS with 3% pre-gelatinized E. Inorganic fertilizer (IF)
(PG) starch F. Soil only
B. EC-DFS with 3% PG starch G. Commercial organic fertilizer or
C. EC-DFS with 3% irradiated (IR) starch poultry manure
D. I-DFS with 3% IR starch
Application rates: 150 & 210 kg N/ha Crops: maize and cabbage
Two (2) soil types
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12. Soil 1 (good forest soil)
At flowering
700
Soil 1 - 150 kg N per ha Soil 1 - 210 kg N per ha
600
Maize fresh weight (g)
500
400
300
200
100
0
EC-SDFS/ EC-DFS/ EC-DFS/ I-DFS/IR Inorg. Soil only Com.
PG PG IR Fert. Comp
Fertilizer label
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13. Soil 2 (typically depleted soil)
At flowering
600
Soil 2 - 150 kg N per ha Soil 2 - 210 kg N per ha
500
Maize fresh weight (g)
400
300
200
100
0
EC-SDFS/ EC-DFS/ EC-DFS/ IR I-DFS/IR Inorg. Fert. Soil only Com.
PG PG Comp
Fertilizer label
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14. Summary of results (I)
Challenge
Disease Fortifer is safe (total CF, E. coli, helminths, heavy metals)
incidence
Transportation With pellets 50-80 % of the initial volume remains
Handling Fortifer pellets are strong and do not easily break
Perception Preliminary market analysis in 4 selected regions of
Ghana confirmed positive response to pellets
Application Dust-free process.
Targeted application of specific amounts.
Composition and nutrient release of the pellets can be
steered according to crop.
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15. Accompanying demand study
1. Identification of market segments (customers)
2. Quantification of segment size and locations
3. Perception studies, WTP, ATP
4. Comparison of WTP with likely costs of compost
production and transport for customer
 First assessment of market demand
FS co-compost
Pelletized, fortified FS co-compost
(different N-P-K configurations)
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16. Market segments for perception and WTP studies
Urban farming systems:
1) Market oriented vegetable farmers
2) Staple crop farmers
3) Backyard farmers Not yet explored
• Mining companies (land rehabilitation)
4) Ornamental flower producers
• Irrigation schemes (paddy)
Peri-urban farming systems: • Forest plantations
1) Vegetable farmers, • Regional expansion (Burkina)
2) Staple crop farmers
3) Fruits plantations (pineapple)
4) Cotton, cocoa, rubber, palm oil plantations (often outgrower systems)
Real estate developers (housing) and landscape designers
Parks & Gardens (municipal departments)
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17. Some results from demand analysis
• 80% of farmers show positive perceptions and are willing to
use and pay for FS co-compost (n=600)
• Reasons for low WTP in general more economic/technical
than cultural
• Revenue scenarios promising, but large variations in the WTP
between different farming systems ( targeted production &
promotion).
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18. Variations between farming systems
• Peri-urban farming system: more tenure security than urban
farmers, more interest in long-term soil fertility build-up.
• Maize-cassava shifting cultivation, or short term vegetables:
interest in quick nutrient injection, not in long-term benefits.
• Smallholders: large group but low WTP; compared new
product with their current product (cheap poultry manure).
• Plantations: high demand and WTP; compared with industrial
fertilizer, but also high quality and packaging requirements.
• Irrigation &. Compost = increased water holding capacity:
Good or bad?
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19. Summary (II)
• Urban agriculture only a tiny market; peri-urban farming
systems much higher demand.
• Construction and plantation sectors are premium customers
for any significant compost sale.
• Smallholder needs could be subsidized through the demand
from premium customers (pro-poor).
• In contrast to plantations, real estate sector has low
requirements on quality and packaging.
• Big Plus: Plantations and estate developers have their own
transport capacities.
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20. Regional analysis
Distribution of Farmers by Acceptability of
FS Co-Compost (n=600)
City Kumasi Accra Tamale
FS acceptable 83 % 74 % 84 %
Unacceptable 17 % 26 % 16 %
Illegal FS use _ + +++
common (raw)
Competing +++ ++ +
products (PM, ...)
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21. The authors would like to express their gratitude to:
• Bill and Melinda Gates Foundation for funding this research;
• All national partners!
Many thanks for your
kind attention !
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