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Sustainability analysis of VESTA integrated with VESTA technology will be of syngas to methane and their integration process schemes for
inside three bio-based process schemes Methodology: key
established in the next few months by me-
for Green-SNG production and the state
ans of a Biomass to-SNG demonstration
methanation technology plant. This paper provides a case study of the art in terms of sustainability of low This Section includes the comparison
carbon applications, the paper proposes Bio-SNG production
with the relevant technical sustainabili-
a new technical assessment to prove the
ty analysis for the renewable application
feasibility of VESTA methanation techno-
between VESTA methanation process and
of VESTA methanation technology to the
to the Bio-SNG production Bio-SNG production from biogas upgra- logy for Bio-SNG production. VESTA me- other available methanation technologies,
ding.
as well as a presentation of three process
thanation was developed and patented by
Foster Wheeler in 2012 and now belongs
schemes to produce Bio-SNG starting
Introduction to the technologies portfolio of Wood, from the syngas produced at the exit of
formed in 2017 following Wood Group’s
biomass gasification, biogas upgrading,
The need to satisfy the ever-increasing acquisition of Amec Foster Wheeler. VE- and Power to Gas systems and including
demand for low carbon-impact fuels has STA methane production technology was the thermochemical conversion (i.e. ca-
given a great boost to the research into initially demonstrated in 2014 for Coal-to- talytic methane production).
new ways of natural gas production by SNG applications in China, where dome- In all methanation processes syngas,
exploiting renewable resources, without stic natural gas resources are not sufficient which is mainly composed by CO and H ,
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losing the possibility to meet domestic to meet domestic demand, while, on the but also H O, CO , CH and N , must be
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and industrial demand. Moreover, the in- contrary, plentiful and more evenly distri- purified before entering the methanation
creasing demand for natural gas and the buted coal reserves are available (Rugge- section, to remove organic contaminants
consequent high prices in the recent past ri and Romano, 2014). When based on (e.g., tar), inorganic contaminants (i.e.
has led many to develop unconventional biomass, the process can help to reduce H S, NH , etc.), and particulate matter.
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methods of natural gas production (Chan- dependency on fossil fuels and help meet The purification step is defined according
del and Williams, 2009). The conversion of environmental targets. Furthermore, the to the impurities to be removed, and parti-
syngas coming from biomass gasification SNG produced can be combusted in any cular attention has to be paid to the sepa-
and biogas upgrading with a suitable me- conventional gas turbine to produce low ration from syngas of sulphur compounds
thanation process scheme provides an al- carbon energy and it can be transported (H S or COS), which shall lead to the poi-
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ternative energy option and distributed soning of the catalysts used in downstre-
for end demand. The using the existing am reactors.
renewable Substitute Bio-SNG is one of the grids and infra-
Natural Gas (SNG) pro- most flexible approaches structure.
duction is one of the The article provi- Methanation processes
most flexible approa-“to decarbonize end des three alter- The verification of the chemical reactions
ches to decarbonise demand, including native renewable involved in the methanation process was
the residential heating simplified process by now consolidated. The methanation
and also transporta- residential heating, schemes to pro- process occurs with the conversion of the
tion systems by using transportation, duce Bio-SNG, carbon oxides, mainly carbon monoxide,
compressed SNG. The and cogeneration i.e. starting from and hydrogen into methane. The catalytic
potentialities of SNG biomass gasifi- synthesis of methane from carbon mono-
are expected to play a cation, biogas xide or carbon dioxide and hydrogen in-
key role in the energy upgrading, and volves the following equilibrium reactions:
sector due to the easy connection of pro- power to gas. Both of the last two pro-
duction plants to existing natural gas net- cess schemes deal with the utilization of CO+3H ↔ CH + H O (1)
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work and the availability of mature techno- renewable hydrogen as reactant, which
logies for commercial application. SNG, is assumed to be produced in electrolytic CO +4H ↔ CH + 2H O (2)
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produced from Biogas, Power to Gas, and cells. Since the schemes presented in this
Biomass gasification, is a clean and low paper are based on the VESTA catalytic Both these reactions are strongly exo-
carbon alternative to conventional natural methanation process, the process cha- thermic, even if CO methanation is less
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gas that can be transported and distribu- racteristics of this methanation technology exothermic than CO methanation. In ad-
ted using the existing grid infrastructure. are deepened as well as the main feature ditions, these reactions occur with moles
For the sake of clarity, SNG produced from of producing SNG from a variety of clean reduction. Hence, in order to provide high
these three renewable pathways is called syngas qualities. For the sake of simplicity, methane yields, low temperatures and high
Green-SNG or Bio-SNG. the advantages of VESTA process sche- pressures are required. Standard metha-
The applications of Green-SNG in the bio me lie in the full flexibility to balance both nation catalysts generally have to work in a
based market sector are several, such as capital and operative expenditures and to reaction temperature range of 250-600°C,
residential heating (including cooking), co- adapt to any source of syngas. while properly stabilized catalysts can to-
generation, and transportation systems. Moreover, the application scale of Green- lerate temperatures up to a maximum of
Ruggeri (2012), Mancuso (2015), and SNG produced from VESTA methanation 700°C. Due to the very large amount of
Stein and Ray (2016) analysed SNG from is very wide, and this article proves heat released during methanation exother-
waste gasification and biogas upgrading the application feasibility of Bio-SNG mic reaction, the criticalities to be faced in
as a clean and low carbon alternative to produced from VESTA methanation from the design of a methanation process is
natural gas. biogas. The results can be extended to a the control of the reactors’ outlet tempe-
Starting from the qualitative description of multiscale basis (e.g., from 1 MWh up to rature (Ulmann’s Encyclopedia, 1989) and
the available technologies for conversion 200 MWh). the capability to recover the reaction heat
Impiantistica Italiana - Novembre-Dicembre 2018 25