Hydrogen production from fruit waste through dark fermentation
Khamdan Cahyari
1,2, Siti Syamsiah
2, Sarto
2, Mohammad J. Taherzadeh
11
School of Engineering, University of Borås, 501 90 Sweden
2
Chemical Engineering, Gadjah Mada University, 552 28 Indonesia
Objectives
This research was meant for investigating the possibility to produce hydrogen from waste of whole fruits generated from agriculture sectors and/or fresh fruit grocery market through dark fermentation process.
Figure 1. General overview of the research
Further Info:
Khamdan Cahyari Khamdan.Cahyari@hb.se Ph. + 46 704 816353 [www.hb.se]
Background
There were more than 400 million tons of fresh fruits being harvested in 2009 to meet global demand. Throughout the cultivation until consumption, some portion of the fruits turn into waste. According to Global Food Losses, at least 10% of fresh fruits turn into waste during cultivation in agriculture sectors (Figure 2). Among the fruits, global top four fruit commodities i.e. melon, banana, apple, and grape were selected as feedstock for the experimental investigation (Figure 3).
Figure 3. Quantity of Fresh Fruit Harvested in 2009 (FAOSTAT UN)
Figure 2. Global Fruit and Vegetables Losses (Food Losses, FAO UN 2011)
Conclusion
Fruit waste is potential raw material for producing renewable H
2through dark fermentation without any methane gas being detected. It benefits downstream purification process for further application such as fuel for fuel cell, internal combustion engine. Considering 10% of global harvested fruits being wasted, total potential H
2production from the four selected fruits reachs 726 million cubic metric .
Methodology
Fruit waste containing organic polymers e.g. carbohydrate is subjected to dark fermentation process in which the polymers are hydrolyzed to sugars. In the presence of microorganisms e.g.
Clostridia, Enterobacteriaceae, sugars are converted into H
2, volatile fatty acids, alcohols (Figure 4.left). Batch biohydrogen production was conducted using serum vial bottles for this research purpose through sequential steps such as grinding, mixing, pH adjustment and incubation at thermopholic condition 55 °C (Figure 4.right)
Figure 4. Metabolic pathways of dark fermentation and
technical methodology. Adapted from (Hallenbeck, Ghosh et al.
2009)
Results and Discussion
Dark fermentation of the selected fruits waste was conducted successfully to produce H
2, without any methane gas being detected.
Among the four, banana yielded higher H
2with potential global production more than 309 million cubic metric based on the 10% of harvested banana in 2009 being wasted. Simulation calculation of H
2production from the four fruits is presented in Table 1. Total H
2production can reach 726 million m
3.
4 th Conference: Hydrogen and Fuel Cells in The Nordic Countries, October 25 th – 26 th 2011, Malmö, Sweden
H2
H2
H2
H2
H2 H2
Fermentation tank
0%
10%
20%
30%
40%
50%
60%
Europe North America
& Oceania
Industrialized Asia
Subsahara Africa
North Africa, West & Central
Asia
South &
Southeast Asia
Latin America
Food losses ‐ Fruits & Vegetables
Consumption Distribution Processing Postharvest Agriculture
Global Food Losses, FAO 2011
0 10 20 30 40 50 60 70 80 90 100 110
Production (tonnes) Millions
Source: FAOSTAT 2009
No Fruits Quantity (tons)
aPercent Wasted
H
2Yield (mmol/g VS)
Potential H
2Production ( STP m
3)
1 Melon 101 000 000 10 5,96 185 808 197
2 Banana 95 000 000 10 8,61 309 093 490
3 Apple 71 700 000 10 7,30 153 941 162
4 Grape 66 900 000 10 7,28 77 457 569
Total 726 300 418
Table 1 Potential H
2production from fruit waste
aVolume of harvested fruit in 2009 (FAO UN)