35
hydroxide, steam explosion and acid reagents, which convert the crystalline structure of SB into polysaccharide elements [254–256]. The results of these thermochemical processes on the chemical structure of the SB can be analysed via enzyme
digestion, electron miscopy and X-ray diffraction [252].
Presently, SB can be utilized in many applications such as cancer treatment,
animal feed, and production of furfural, sugar, pulp and ethanol [252, 253].
Furthermore, SB is a suitable feedstock to be applied as a renewable resource due to
its low cost and high availability [252, 257]. SB is mostly used for power and heat
generation through combustion route, which is not energy efficient [250, 253].
However, SB can be applied for the production of biofuel through advanced thermochemical processes due to its high caloric value and availability, thus making this
material a valuable feedstock for pyrolysis technology [250].
9 Conclusion
Renewable and sustainable energy sources have received attention because of the
increase in demand for fossil fuels and concerns regarding climate change. Biofuels
are characterized into “primary biofuels” and “secondary biofuels”. The traditional
form of biofuel for heat and electricity generation is categorized in “primary biofuels”. The second class of biofuels is characterized into first, second and third generations. First-generation biofuels are mainly produced from sugar, food crops and
starch. Second-generation biofuels are formed from non-food biomass, and thirdgeneration biofuels are made from microbes and microalgae. Pyrolysis is an
advanced thermal conversion method for converting biomass into useful chemicals
and energy carriers. Pyrolysis methods can be divided into three primary types
which are fast, intermediate and slow pyrolysis. Slow pyrolysis is suitable for biochar formation and utilization. The main difference between slow, intermediate and
fast pyrolysis methods is the solid residence times that cause a different heat transfer
to the material.
TCR is a novel technology that combines the intermediate pyrolysis with postcatalytic treatment (catalytic reforming) in a single-step upgrading. In the reforming
stage, vapour catalytic cracking happens to encourage the formation of syngas and
organic vapours with lower molecular weight compounds. TCR bio-oil has superior
physicochemical fuel characteristics in comparison with other technologies. TCR
bio-oil of woody biomass is low in oxygen content (11.4–17.9 wt%), low in viscosity (12.1–36.5 mm
2
/s) and low in acidity (9.3–30.1 mg KOH/g) and has a very high
heating value (32.8–35.5 MJ/kg) compared to bio-oil of fast pyrolysis. TCR bio-oil
can be separated simply from the water phase and is totally miscible with conventional fossil fuels. There is no need for using expensive catalysts such as zeolite or/
and precious metal oxide catalysts in this process. TCR technology is well compatible with different ranges of feedstocks that are high in ash and moisture contents.
Furthermore, TCR produces a significant amount of green H 2 for hydrotreatment of
bio-oil and can be maximized by injection of steam into the system that promotes a
Thermochemical Conversion of Biomass and Upgrading of Bio-Products to Produce…
hydroxide, steam explosion and acid reagents, which convert the crystalline structure of SB into polysaccharide elements [254–256]. The results of these thermochemical processes on the chemical structure of the SB can be analysed via enzyme
digestion, electron miscopy and X-ray diffraction [252].
Presently, SB can be utilized in many applications such as cancer treatment,
animal feed, and production of furfural, sugar, pulp and ethanol [252, 253].
Furthermore, SB is a suitable feedstock to be applied as a renewable resource due to
its low cost and high availability [252, 257]. SB is mostly used for power and heat
generation through combustion route, which is not energy efficient [250, 253].
However, SB can be applied for the production of biofuel through advanced thermochemical processes due to its high caloric value and availability, thus making this
material a valuable feedstock for pyrolysis technology [250].
9 Conclusion
Renewable and sustainable energy sources have received attention because of the
increase in demand for fossil fuels and concerns regarding climate change. Biofuels
are characterized into “primary biofuels” and “secondary biofuels”. The traditional
form of biofuel for heat and electricity generation is categorized in “primary biofuels”. The second class of biofuels is characterized into first, second and third generations. First-generation biofuels are mainly produced from sugar, food crops and
starch. Second-generation biofuels are formed from non-food biomass, and thirdgeneration biofuels are made from microbes and microalgae. Pyrolysis is an
advanced thermal conversion method for converting biomass into useful chemicals
and energy carriers. Pyrolysis methods can be divided into three primary types
which are fast, intermediate and slow pyrolysis. Slow pyrolysis is suitable for biochar formation and utilization. The main difference between slow, intermediate and
fast pyrolysis methods is the solid residence times that cause a different heat transfer
to the material.
TCR is a novel technology that combines the intermediate pyrolysis with postcatalytic treatment (catalytic reforming) in a single-step upgrading. In the reforming
stage, vapour catalytic cracking happens to encourage the formation of syngas and
organic vapours with lower molecular weight compounds. TCR bio-oil has superior
physicochemical fuel characteristics in comparison with other technologies. TCR
bio-oil of woody biomass is low in oxygen content (11.4–17.9 wt%), low in viscosity (12.1–36.5 mm
2
/s) and low in acidity (9.3–30.1 mg KOH/g) and has a very high
heating value (32.8–35.5 MJ/kg) compared to bio-oil of fast pyrolysis. TCR bio-oil
can be separated simply from the water phase and is totally miscible with conventional fossil fuels. There is no need for using expensive catalysts such as zeolite or/
and precious metal oxide catalysts in this process. TCR technology is well compatible with different ranges of feedstocks that are high in ash and moisture contents.
Furthermore, TCR produces a significant amount of green H 2 for hydrotreatment of
bio-oil and can be maximized by injection of steam into the system that promotes a
Thermochemical Conversion of Biomass and Upgrading of Bio-Products to Produce…