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Table 1 - Performance Data of Bio-SNG production from biomass gasification. Efficiency is defined as
the ratio of produced SNG thermal power and inlet biomass thermal power. The SNG production costs is
based on the following assumptions: biomass cost of 22 €/ton, full equity, I.R.R. 8%
Item Value Unit
Feedstock flowrate 130 t/h
Inlet thermal power 315-330 MWh
3
Outlet SNG flowrate 21,000 Nm /h
Efficiency up to 67 %
Total Investment Cost (TIC) 340-370 M€
SNG production cost 13.0 $/MMBtu

Table 2 - Performance Data of Bio-SNG production from biogas upgrading
Item Value Unit
Feedstock flowrate 0.5 t/h
Inlet biogas thermal power 3 MWh
Inlet renewable hydrogen 550 Nm /h
3
Electrical power required for renewable hydrogen production 2.3 MW
Outlet SNG flowrate 455 Nm /h
3
Electrical power to SNG efficiency 61 %

composed of CO and H ) can contain also H O, CO , on the selected gasification technology with an impact Fig. 4 - Biogas
2
2
2
CH and N together with organic and inorganic on the downstream syngas conditioning and cleaning upgrading to SNG
4 2
contaminants and must be purified before the steps [10]. A typical conceptual scheme of a biomass block flow diagram
methanation process, in order to avoid the irreversible gasification to SNG is reported in figure 3.
deactivation of the downstream catalyst [9]. All the Today, more than ever, the biobased sector is
required technologies for the polishing steps and the seeing the interest and investment of the main EU
subsequent methanation are by now ready on the members. Considering these current incentives,
market and Wood has all the capabilities to manage all the biomass gasification followed by a suitable
the process blocks at full industrial scale. For instance, polishing step and the clean gas methanation is a
tar can be removed through specific processes viable and economically attractive solution to
downstream of the gasifier, such as water scrubbing, oil produce Bio-SNG and Wood is actively working in
scrubbing, thermal cracking, and catalytic cracking. this market. Table 1 provides the technical and
Organic contaminants (e.g. tar), inorganic contaminants economical assessment of an industrial scale
(e.g. H S, NH ) and particulate matter can be removed biomass gasification and SNG plant, using woody
2 3
through either physical or chemical absorption. materials as feedstock.
Particular attention has to be paid in conditioning the The main input data are relevant to the woody
syngas for SNG production from biomass gasification material feedstock and the outlet thermal power of
due to the variety of compositions hidden behind the produced SNG of approximately 200 MWh, which
term “biomass”. SNG can be produced from biomass correspond to a product flowrate of 21,000 Nm3/h.
by using different plant configurations, which depend The final clean-up is based on catalytic reforming

IndustrIal Plants - May 2018
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