tons production every year. Kang et al. (2014) opined that the abundant lignocellulosic wastes found in nature make them a good feedstock for biogas
production and can add approximately 1500 MJ/year of energy. Although they
are difficult to be digested (Himmel and Picataggio 2009). The lignocellulosic
feedstock which was used for anaerobic digestion was silage maize (Mumme
et al. 2011). Cadavid-Rodríguez and Bolaños-Valencia (2016) used grass silage
for anaerobic digestion and found that maximum methane was seen when the
total solids were at 4% composition. Liew et al. (2012) studied the use of wheat
straw, corn stover, yard waste, and leaves for biomethane production through
anaerobic digestion and found that corn stover was the best feedstock for
generation of methane followed by wheat straw, leaves, and yard waste. Sugarcane bagasse was treated with alkali to remove lignin which improved the rate of
lignin removal. The maximum methane yields were found to be about 221.8 mL/
g-VS (Kumari and Das 2015). Battista et al. (2016) used the lignocellulosic
materials in coffee wastes by pretreating them with sodium hydroxide and
observed a higher biogas production with pretreated coffee waste. Forestry
residues were also used as feedstock for biogas production by pretreatment
(Teghammar et al. 2014). Oil palm fiber from a Colombian palm oil mill was
studied for generation of biogas (Garcia-Nunez et al. 2016a). Different types of
agricultural residues from maize, coffee, cotton, sugarcane, and bananas were
found to be suitable as feedstock for biogas production in Kenya (Santa-Maria
et al. 2013; Nzila et al. 2017). Co-digestion of food waste and straw at 35
C was
studied by Yong et al. (2015). Brown and Li (2013) and Xu and Li (2012) have
reported that co-digestion of food waste and lignocellulosic wastes helps maintain a carbon/nitrogen ratio, reduction of the start-up time, and volatile fatty acid
accumulation thereby improving the overall biomethane production. Lott et al.
(2020) produced high purity methane by adding H 2 and CO 2 through the process
known as ex situ biogas upgrading in which agro-municipal residues such as
cow manure (CM) and the organic fraction of solid municipal waste (OFSMW)
were used. Agata et al. have used mild thermal pretreatment of kitchen waste and
concluded it was helpful in the solubilization of macromolecules and proposed it
as a promising option for enhancing biogas production. Rasapoor et al. (2020)
reviewed the challenges involved in improving biogas generation and suggested
balancing the waste composition, optimizing nutrient, and using additives like
biochar, carbon, and phenazine for direct interspecies electron transfer (DIET).
Lim et al. (2020a) studied the influence of seed sludge on microbial diversity and
performance of thermophilic digestion of food waste. Lim et al. (2020b) proposed the use of biochar for overcoming process instability during start-up of the
anaerobic digestion process. They observed that biochar addition enhanced the
methane production by 18%. When biochar was added, the growth of
electroactive Clostridia and other electroactive bacteria was seen, while in its
absence, biochar promoted the growth of Clostridia and syntrophic acetate
oxidizing bacteria. The types of feedstocks are shown in Table 8.3.
8 Bioprocess Parameters for Thermophilic and Mesophilic Biogas Production: Recent. . . 237
production and can add approximately 1500 MJ/year of energy. Although they
are difficult to be digested (Himmel and Picataggio 2009). The lignocellulosic
feedstock which was used for anaerobic digestion was silage maize (Mumme
et al. 2011). Cadavid-Rodríguez and Bolaños-Valencia (2016) used grass silage
for anaerobic digestion and found that maximum methane was seen when the
total solids were at 4% composition. Liew et al. (2012) studied the use of wheat
straw, corn stover, yard waste, and leaves for biomethane production through
anaerobic digestion and found that corn stover was the best feedstock for
generation of methane followed by wheat straw, leaves, and yard waste. Sugarcane bagasse was treated with alkali to remove lignin which improved the rate of
lignin removal. The maximum methane yields were found to be about 221.8 mL/
g-VS (Kumari and Das 2015). Battista et al. (2016) used the lignocellulosic
materials in coffee wastes by pretreating them with sodium hydroxide and
observed a higher biogas production with pretreated coffee waste. Forestry
residues were also used as feedstock for biogas production by pretreatment
(Teghammar et al. 2014). Oil palm fiber from a Colombian palm oil mill was
studied for generation of biogas (Garcia-Nunez et al. 2016a). Different types of
agricultural residues from maize, coffee, cotton, sugarcane, and bananas were
found to be suitable as feedstock for biogas production in Kenya (Santa-Maria
et al. 2013; Nzila et al. 2017). Co-digestion of food waste and straw at 35
C was
studied by Yong et al. (2015). Brown and Li (2013) and Xu and Li (2012) have
reported that co-digestion of food waste and lignocellulosic wastes helps maintain a carbon/nitrogen ratio, reduction of the start-up time, and volatile fatty acid
accumulation thereby improving the overall biomethane production. Lott et al.
(2020) produced high purity methane by adding H 2 and CO 2 through the process
known as ex situ biogas upgrading in which agro-municipal residues such as
cow manure (CM) and the organic fraction of solid municipal waste (OFSMW)
were used. Agata et al. have used mild thermal pretreatment of kitchen waste and
concluded it was helpful in the solubilization of macromolecules and proposed it
as a promising option for enhancing biogas production. Rasapoor et al. (2020)
reviewed the challenges involved in improving biogas generation and suggested
balancing the waste composition, optimizing nutrient, and using additives like
biochar, carbon, and phenazine for direct interspecies electron transfer (DIET).
Lim et al. (2020a) studied the influence of seed sludge on microbial diversity and
performance of thermophilic digestion of food waste. Lim et al. (2020b) proposed the use of biochar for overcoming process instability during start-up of the
anaerobic digestion process. They observed that biochar addition enhanced the
methane production by 18%. When biochar was added, the growth of
electroactive Clostridia and other electroactive bacteria was seen, while in its
absence, biochar promoted the growth of Clostridia and syntrophic acetate
oxidizing bacteria. The types of feedstocks are shown in Table 8.3.
8 Bioprocess Parameters for Thermophilic and Mesophilic Biogas Production: Recent. . . 237