According to USEPA, 1000 kg of food waste have the potential of producing 376 m
3
of biogas (Ali et al. 2019). The highest food waste generation rate is 0.5 kg per capita
per day in Canada, then 0.37 and 0.3 kg per capita per day in England and the United
States, respectively. In developing countries, India, China, and Brazil have the
maximum food waste generation rates (Dung et al. 2014).
2.3.4 Co-digestion of Multiple Wastes
The efficiency of anaerobic digesters can be increased by using more than one waste
type in a single digester, also known as co-digestion. It is reported that up to 43%
methane production can be improved because of the synergetic effects (Horváth
et al. 2016). In Germany, grass and maize silage are commonly digested together in
biogas plants (Nizami et al. 2009). Co-digestion of poultry waste and rice husk is
also suggested to produce energy and considered being cost beneficent and environmentally sustainable procedure (Arshad et al. 2018). About 220 kg of rice husk can
be produced from one ton of rice paddy, and its potential of producing energy can be
estimated from the fact that one ton of rice husk can generate up to 570 kWh
electricity (Ali et al. 2016). Agricultural residues combined with livestock waste
and food waste is also a very promising co-digestion strategy to enhance environmentally friendly biogas generation (Hagos et al. 2017).
2.4
Microbial and Biological Advancement
A complex microbial process is responsible for efficient biogas generation through
the action of numerous microbial species utilizing different substrates as feedstock.
These organisms need to work collectively to attain maximum output. Thus, a simple
principle is to introduce anaerobic microorganisms for the degradation of the organic
material which is kept in an air-tight container for ensuring that no oxygen enters it
(Schnürer and Jarvis 2018).
2.4.1 Environmental Influences
These microorganisms require an appropriate environment for multiplication and
accomplishment of their function. Some significant ecological aspects of development are:
• Temperature
• O 2 concentration
• pH
• Salt content
44
M. N. Anwar et al.
3
of biogas (Ali et al. 2019). The highest food waste generation rate is 0.5 kg per capita
per day in Canada, then 0.37 and 0.3 kg per capita per day in England and the United
States, respectively. In developing countries, India, China, and Brazil have the
maximum food waste generation rates (Dung et al. 2014).
2.3.4 Co-digestion of Multiple Wastes
The efficiency of anaerobic digesters can be increased by using more than one waste
type in a single digester, also known as co-digestion. It is reported that up to 43%
methane production can be improved because of the synergetic effects (Horváth
et al. 2016). In Germany, grass and maize silage are commonly digested together in
biogas plants (Nizami et al. 2009). Co-digestion of poultry waste and rice husk is
also suggested to produce energy and considered being cost beneficent and environmentally sustainable procedure (Arshad et al. 2018). About 220 kg of rice husk can
be produced from one ton of rice paddy, and its potential of producing energy can be
estimated from the fact that one ton of rice husk can generate up to 570 kWh
electricity (Ali et al. 2016). Agricultural residues combined with livestock waste
and food waste is also a very promising co-digestion strategy to enhance environmentally friendly biogas generation (Hagos et al. 2017).
2.4
Microbial and Biological Advancement
A complex microbial process is responsible for efficient biogas generation through
the action of numerous microbial species utilizing different substrates as feedstock.
These organisms need to work collectively to attain maximum output. Thus, a simple
principle is to introduce anaerobic microorganisms for the degradation of the organic
material which is kept in an air-tight container for ensuring that no oxygen enters it
(Schnürer and Jarvis 2018).
2.4.1 Environmental Influences
These microorganisms require an appropriate environment for multiplication and
accomplishment of their function. Some significant ecological aspects of development are:
• Temperature
• O 2 concentration
• pH
• Salt content
44
M. N. Anwar et al.