scrubbing method, amine scrubbing method, membrane technology, cryogenic
technology, chemical dehydrogenation method and industrial lung method, respectively. For supersonic method and pressure swing adsorption method, low temperature is demanded. In contrast to this, high temperature is a demand for temperature
swing adsorption method. The partial load range is about 50–100%, 85–115%,
50–100%, 50–105% and 50–100% for pressurised water scrubbing method, amine
scrubbing method, organic physical scrubbing method, pressure swing adsorption
method and membrane technology (Angelidaki et al. 2018).
The in situ methane enrichment technique is operatively easy and with a major
disadvantage of its use only in small-scale plants (Petersson and Wellinger 2009). In
industrial lung upgrading technology, the major drawback lies in the enzyme used.
As the enzyme used has limited life time, the validity of this technique is challenged,
but this method can overcome high temperature (Sahota et al. 2018).
Consequently, the problem of operational issue exists for all upgraded technology, and it can be moved out of the context only if the technologies are combined
giving rise to the hybrid type of technologies. Comparing the operational indicators
of conventional methods and biological method, the biological methods are a
biomass-dependent process and require consumables but has a disadvantage of
low gas–liquid mass transfer rate (in ex situ chemoautotrophic method). The temperature requirements for ex situ chemoautotrophic and in situ chemoautotrophic
method are 35–55
C and 37–55
C, respectively (Angelidaki et al. 2018).
(e) Social Indicators
The acceptance of a technology is based on the environmental impacts generated.
Green technologies are forthcoming, and such upgrading technologies are acceptable since it overcomes the problem of greenhouse gas emissions, indirectly pleasing
the environment. Based on this, the biological methods are accepted more by the
society than the conventional physical/chemical methods such as organic physical
scrubbing that requires a large amount of chemicals (Toledo-Cervantes et al. 2017).
The microbial electrochemical method is found to be one of the sustainable
methods that can be upgraded for generating environmentally pleasing solutions
(Lovely and Nevin 2013). In fermentation method, the CO 2 solubility is high that
favours a sustainable environment.
9.7
Future Perspective in Biogas Upgradation
Currently, biogas finds novel application in wide areas besides power and heat
production. Most of the countries rely upon biomethane production from the
generated biogas. Among the biogas upgradation technologies, physical and chemical methods are in demand, while biological methods are not commercialised even
though it provides technological easiness and high feasibility and that seems to be
the major challenge to be unwinded (Fig. 9.5). Biological upgradation paves new
9 Recent Trends in Biogas Upgrading Technologies for Biomethane Production
273
technology, chemical dehydrogenation method and industrial lung method, respectively. For supersonic method and pressure swing adsorption method, low temperature is demanded. In contrast to this, high temperature is a demand for temperature
swing adsorption method. The partial load range is about 50–100%, 85–115%,
50–100%, 50–105% and 50–100% for pressurised water scrubbing method, amine
scrubbing method, organic physical scrubbing method, pressure swing adsorption
method and membrane technology (Angelidaki et al. 2018).
The in situ methane enrichment technique is operatively easy and with a major
disadvantage of its use only in small-scale plants (Petersson and Wellinger 2009). In
industrial lung upgrading technology, the major drawback lies in the enzyme used.
As the enzyme used has limited life time, the validity of this technique is challenged,
but this method can overcome high temperature (Sahota et al. 2018).
Consequently, the problem of operational issue exists for all upgraded technology, and it can be moved out of the context only if the technologies are combined
giving rise to the hybrid type of technologies. Comparing the operational indicators
of conventional methods and biological method, the biological methods are a
biomass-dependent process and require consumables but has a disadvantage of
low gas–liquid mass transfer rate (in ex situ chemoautotrophic method). The temperature requirements for ex situ chemoautotrophic and in situ chemoautotrophic
method are 35–55
C and 37–55
C, respectively (Angelidaki et al. 2018).
(e) Social Indicators
The acceptance of a technology is based on the environmental impacts generated.
Green technologies are forthcoming, and such upgrading technologies are acceptable since it overcomes the problem of greenhouse gas emissions, indirectly pleasing
the environment. Based on this, the biological methods are accepted more by the
society than the conventional physical/chemical methods such as organic physical
scrubbing that requires a large amount of chemicals (Toledo-Cervantes et al. 2017).
The microbial electrochemical method is found to be one of the sustainable
methods that can be upgraded for generating environmentally pleasing solutions
(Lovely and Nevin 2013). In fermentation method, the CO 2 solubility is high that
favours a sustainable environment.
9.7
Future Perspective in Biogas Upgradation
Currently, biogas finds novel application in wide areas besides power and heat
production. Most of the countries rely upon biomethane production from the
generated biogas. Among the biogas upgradation technologies, physical and chemical methods are in demand, while biological methods are not commercialised even
though it provides technological easiness and high feasibility and that seems to be
the major challenge to be unwinded (Fig. 9.5). Biological upgradation paves new
9 Recent Trends in Biogas Upgrading Technologies for Biomethane Production
273