concentration of the petroleum product is present. The remaining oil has been shown
to be converted to natural gas by a methanogenic consortium that was associated
with the oil field (Jiang et al. 2014). The consortium used was derived from satellite
sediments and can be enriched with crude oil. Bacteroidetes, Clostridiales,
Methanosaeta sp., etc. are this type of methanogen.
Archaeologists are still struggling to gather enough evidence before reaching the
final conclusions about the effectiveness of citrophic sulfate-reducing bacteria.
Methane collected from the coal bed is the general methane source. Around 50%
of this methane gas is generated by methanogenic bacteria present in the environment. Responsible aromatic constituents inside the coal bed are used as a substrate
for this production (Mayumi et al. 2016). In this regard, it reveals that
Methermicoccus shengliensis species can generate 11 microliter of methane gas
from 1 g of coal. This methane gas is already consumed by various manufacturing
units. It is also predicted by the researcher that this strain may be used for the
production of the methane from other various sources.
Almost 82% of the world’s industry waste is polluted by the metallic as well as
organic pollutants. Statistics collected from both anaerobic and aerobic schemes
prove that biological degradation of the organic matter can be decreased by the toxic
nature of metal. Failure to consider metallic organic availability instead of total
metals probably leads to metallic organic availability leading to substantial variability in the reporting of resistive densities of metals that affect the amount of metallic
organic presence. Metals usually affect biodegradation. Latest methods to enhance
biodegradation in the presence of metals include a reduction in the bioavailability of
metals and the use of metal-resistant bacteria, additives of the treatment process, and
soil minerals. Some metal is used as a catalyst in this biomethanation process. For
example, iron in the form of ion if present in the biomethanation process accelerates
the process. One of the theories behind it is it increases the activity of the
methanogen by changing the electrons from the metals (Carpenter et al. 2015). It
is also observed that the presence of hydrogen in the system can enhance the
production of biogas. A methanogenic bioelectrochemical system (BES) is introduced and works on the simultaneous combination action of these two theories to
enhance the biogas production. In this system, the current is passed through the
system by means of the electrode connected with the system. Here, the bacteria can
either consume the produced hydrogen at the cathode or directly gain the electron
from the anode (Geppert et al. 2016). The effects of different metals on the
production of biogas in the form of methane were studied by a few scholars
(Carpenter et al. 2015; Geppert et al. 2016). It has been found that molybdenum,
magnesium, cobalt, calcium, iron, as well as nickel separately as well as in grouping
have enhanced the production of biogas in the form of methane and this is responsible for the increasing methanogenic bacteria in the reactor.
The shape, size, as well as material of construction of the membrane and electrode
and the strength of the current that passed through the electrodes highly affect the
electromethanogenesis action (Babanova et al. 2017; Krieg et al. 2014; Ribot-Llobet
et al. 2013; Siegert et al. 2014). It is also observed that the favorable conditions for
3 A Comprehensive Review on Microbial Technology for Biogas Production
73
to be converted to natural gas by a methanogenic consortium that was associated
with the oil field (Jiang et al. 2014). The consortium used was derived from satellite
sediments and can be enriched with crude oil. Bacteroidetes, Clostridiales,
Methanosaeta sp., etc. are this type of methanogen.
Archaeologists are still struggling to gather enough evidence before reaching the
final conclusions about the effectiveness of citrophic sulfate-reducing bacteria.
Methane collected from the coal bed is the general methane source. Around 50%
of this methane gas is generated by methanogenic bacteria present in the environment. Responsible aromatic constituents inside the coal bed are used as a substrate
for this production (Mayumi et al. 2016). In this regard, it reveals that
Methermicoccus shengliensis species can generate 11 microliter of methane gas
from 1 g of coal. This methane gas is already consumed by various manufacturing
units. It is also predicted by the researcher that this strain may be used for the
production of the methane from other various sources.
Almost 82% of the world’s industry waste is polluted by the metallic as well as
organic pollutants. Statistics collected from both anaerobic and aerobic schemes
prove that biological degradation of the organic matter can be decreased by the toxic
nature of metal. Failure to consider metallic organic availability instead of total
metals probably leads to metallic organic availability leading to substantial variability in the reporting of resistive densities of metals that affect the amount of metallic
organic presence. Metals usually affect biodegradation. Latest methods to enhance
biodegradation in the presence of metals include a reduction in the bioavailability of
metals and the use of metal-resistant bacteria, additives of the treatment process, and
soil minerals. Some metal is used as a catalyst in this biomethanation process. For
example, iron in the form of ion if present in the biomethanation process accelerates
the process. One of the theories behind it is it increases the activity of the
methanogen by changing the electrons from the metals (Carpenter et al. 2015). It
is also observed that the presence of hydrogen in the system can enhance the
production of biogas. A methanogenic bioelectrochemical system (BES) is introduced and works on the simultaneous combination action of these two theories to
enhance the biogas production. In this system, the current is passed through the
system by means of the electrode connected with the system. Here, the bacteria can
either consume the produced hydrogen at the cathode or directly gain the electron
from the anode (Geppert et al. 2016). The effects of different metals on the
production of biogas in the form of methane were studied by a few scholars
(Carpenter et al. 2015; Geppert et al. 2016). It has been found that molybdenum,
magnesium, cobalt, calcium, iron, as well as nickel separately as well as in grouping
have enhanced the production of biogas in the form of methane and this is responsible for the increasing methanogenic bacteria in the reactor.
The shape, size, as well as material of construction of the membrane and electrode
and the strength of the current that passed through the electrodes highly affect the
electromethanogenesis action (Babanova et al. 2017; Krieg et al. 2014; Ribot-Llobet
et al. 2013; Siegert et al. 2014). It is also observed that the favorable conditions for
3 A Comprehensive Review on Microbial Technology for Biogas Production
73