experience. However, both VFAs and siloxanes are biodegradable molecules and
their removal from biogas could be eventually carried out using biotechnologies,
which would a priori support a better environmental and economic performance
(Accettola et al. 2008).
Acknowledgements The financial support from MINECO and the FEDER funding programme is
gratefully acknowledged (CTM2015-70442-R). The project has received funding from the
European Union’s Horizon 2020 research and innovation programme under grant agreement
No. 689242. David Jeison acknowledges the support provided by CRHIAM Centre (CONICYT/
FONDAP/15130015).
Table 8 Technologies for the removal of H 2 S from biogas
Technology
Fundamentals
Design
parameters
Operational
parameters
Adsorption
Adsorption + reaction in an
adsorbent packed bed
1 Adsorption
column + 1
desorption
column
Adsorbent:
Fe 2 O 3 , Fe(OH) 3
and ZnO
Empty bed residence
time = 1–15 min
Adsorption capacity
of activated carbon:
0.1–0.2 g H 2 S/g
carbon
Chemical
precipitation
Addition to the digester of
FeCl 2 , FeCl 3 and FeSO 4
2 salts to
promote the in situ precipitation
of FeS
Levels of H 2 S in
the treated
biogas > 100–
150 ppm v
Dosing
ratio = 0.035 kg
FeCl 3 /kg Total solid
Photosynthetic
H 2 S removal
Aerobic oxidation of H 2 S by
chemolitotrophic bacteria using
the O 2 produced
photosynthetically by
microalgae in the
photobioreactor
H 2 S
removals > 99%
Liquid to biogas ratio
0.5–2 between the
absorption column
and the HRAP
Biotrickling
filtration
Aerobic or anoxic oxidation of
H 2 S in a packed bed column
containing a biofilm of
chemolitotrophic bacteria
supplied with nutrients from a
recirculating aqueous solution
H 2 S
removals > 99%
Empty bed residence
time = 2–10 min
Microaerobic
anaerobic
digestion
O 2 dosing in the headspace of
the anaerobic digester to
support the partial oxidation of
H 2 S to elemental sulphur that
accumulates in the digester
headspace
H 2 S
removals > 99%
Empty bed residence
time = 5 h
O2/biogas flow rate
ratio = 0.3–3%
12 Biofuels from Microalgae: Biomethane
265
their removal from biogas could be eventually carried out using biotechnologies,
which would a priori support a better environmental and economic performance
(Accettola et al. 2008).
Acknowledgements The financial support from MINECO and the FEDER funding programme is
gratefully acknowledged (CTM2015-70442-R). The project has received funding from the
European Union’s Horizon 2020 research and innovation programme under grant agreement
No. 689242. David Jeison acknowledges the support provided by CRHIAM Centre (CONICYT/
FONDAP/15130015).
Table 8 Technologies for the removal of H 2 S from biogas
Technology
Fundamentals
Design
parameters
Operational
parameters
Adsorption
Adsorption + reaction in an
adsorbent packed bed
1 Adsorption
column + 1
desorption
column
Adsorbent:
Fe 2 O 3 , Fe(OH) 3
and ZnO
Empty bed residence
time = 1–15 min
Adsorption capacity
of activated carbon:
0.1–0.2 g H 2 S/g
carbon
Chemical
precipitation
Addition to the digester of
FeCl 2 , FeCl 3 and FeSO 4
2 salts to
promote the in situ precipitation
of FeS
Levels of H 2 S in
the treated
biogas > 100–
150 ppm v
Dosing
ratio = 0.035 kg
FeCl 3 /kg Total solid
Photosynthetic
H 2 S removal
Aerobic oxidation of H 2 S by
chemolitotrophic bacteria using
the O 2 produced
photosynthetically by
microalgae in the
photobioreactor
H 2 S
removals > 99%
Liquid to biogas ratio
0.5–2 between the
absorption column
and the HRAP
Biotrickling
filtration
Aerobic or anoxic oxidation of
H 2 S in a packed bed column
containing a biofilm of
chemolitotrophic bacteria
supplied with nutrients from a
recirculating aqueous solution
H 2 S
removals > 99%
Empty bed residence
time = 2–10 min
Microaerobic
anaerobic
digestion
O 2 dosing in the headspace of
the anaerobic digester to
support the partial oxidation of
H 2 S to elemental sulphur that
accumulates in the digester
headspace
H 2 S
removals > 99%
Empty bed residence
time = 5 h
O2/biogas flow rate
ratio = 0.3–3%
12 Biofuels from Microalgae: Biomethane
265