OMW
Olive mill waste
P H 2
Hydrogen partial pressure
POME
Palm oil mill effluent
SBR
Sequencing batch reactor
UASB
Upflow anaerobic sludge blanket
VFAs
Volatile fatty acids
VS
Volatile solids
VSS
Volatile suspended solids
1 Introduction
Recovering energy and nutrients from industrial waste enhances the sustainability of
the treatment methods used to mitigate the environmental impact of such waste.
Converting organic industrial wastes to hydrogen (H 2 ) contributes to pollution
control and economic gain (resources recovery and offset part of waste management
cost by revenue generated from biofuel production).
Biological treatment methods use biocatalyst to stabilize organic waste. These
methods are reliable, cost-effective, and environmental-friendly. Anaerobic digestion is the most important biological process which could treat waste and generate
bioenergy. Energy could be extracted from the anaerobic digestion of domestic,
industrial, and agricultural waste as methane (CH 4 ) or with slight operation control
as hydrogen (H 2 ). H 2 is more energetic than CH 4 (based on the energy content per
unit mass), and it does not produce CO 2 when combusted. The latter characteristic of
H 2 is advantageous and allows for more efficient CO 2 capture and sequestration at
the fermentation site; therefore, H 2 is preferred over CH 4 as the end product of
anaerobic digestion. The energy yield of anaerobic digestion is increased when H 2 is
recovered instead of CH 4 . To be sustainable, all the components of the H 2 production process have to be sustainable. Therefore, the feedstock, biocatalyst (inoculum),
and any other input material should be obtained from renewable and sustainable
sources. Organic industrial wastes from processes such as food processing, brewery,
winery, slaughterhouses, bakery, etc. are ideal substrates for H 2 production. Anaerobic mixed culture can easily be obtained from many natural environments such as
agricultural soil, animal dung, and/or man-made environments such as compost and
anaerobic digesters in municipal and industrial wastewater treatment plants. The use
of anaerobic mixed culture to digest organic industrial waste closes the cycle and
makes the H 2 production process more sustainable. This chapter provides the current
state of the art of H 2 production through anaerobic mixed culture dark fermentation
of industrial waste.
Hydrolytic and fermentative bacteria can convert waste rich in carbohydrates to
H 2 and short-chain volatile fatty acids. Therefore, utilizing carbohydrate-containing
waste for biohydrogen production via mixed-culture dark fermentation has been
investigated frequently. The wastes from food and agro-product industries such as
8 Biohydrogen of Industrial Waste
325
Olive mill waste
P H 2
Hydrogen partial pressure
POME
Palm oil mill effluent
SBR
Sequencing batch reactor
UASB
Upflow anaerobic sludge blanket
VFAs
Volatile fatty acids
VS
Volatile solids
VSS
Volatile suspended solids
1 Introduction
Recovering energy and nutrients from industrial waste enhances the sustainability of
the treatment methods used to mitigate the environmental impact of such waste.
Converting organic industrial wastes to hydrogen (H 2 ) contributes to pollution
control and economic gain (resources recovery and offset part of waste management
cost by revenue generated from biofuel production).
Biological treatment methods use biocatalyst to stabilize organic waste. These
methods are reliable, cost-effective, and environmental-friendly. Anaerobic digestion is the most important biological process which could treat waste and generate
bioenergy. Energy could be extracted from the anaerobic digestion of domestic,
industrial, and agricultural waste as methane (CH 4 ) or with slight operation control
as hydrogen (H 2 ). H 2 is more energetic than CH 4 (based on the energy content per
unit mass), and it does not produce CO 2 when combusted. The latter characteristic of
H 2 is advantageous and allows for more efficient CO 2 capture and sequestration at
the fermentation site; therefore, H 2 is preferred over CH 4 as the end product of
anaerobic digestion. The energy yield of anaerobic digestion is increased when H 2 is
recovered instead of CH 4 . To be sustainable, all the components of the H 2 production process have to be sustainable. Therefore, the feedstock, biocatalyst (inoculum),
and any other input material should be obtained from renewable and sustainable
sources. Organic industrial wastes from processes such as food processing, brewery,
winery, slaughterhouses, bakery, etc. are ideal substrates for H 2 production. Anaerobic mixed culture can easily be obtained from many natural environments such as
agricultural soil, animal dung, and/or man-made environments such as compost and
anaerobic digesters in municipal and industrial wastewater treatment plants. The use
of anaerobic mixed culture to digest organic industrial waste closes the cycle and
makes the H 2 production process more sustainable. This chapter provides the current
state of the art of H 2 production through anaerobic mixed culture dark fermentation
of industrial waste.
Hydrolytic and fermentative bacteria can convert waste rich in carbohydrates to
H 2 and short-chain volatile fatty acids. Therefore, utilizing carbohydrate-containing
waste for biohydrogen production via mixed-culture dark fermentation has been
investigated frequently. The wastes from food and agro-product industries such as
8 Biohydrogen of Industrial Waste
325