Paper Technology International 2025 FlipBook - Journal - Page 24
PAPERTECHNOLOGYINTERNATIONAL
Figure 5: Local and circular energy system. The energy model
at the Kisa mill, developed by Meva Energy showcases use of
locally sourced biomass waste to produce high-quality renewable gas and biochar at the production site, contributing to both
environmental and economic sustainability.
Renewable gas production directly at the mill
The philosophy of the Kisa mill is to produce gas on-site,
using with locally generated biogenic waste streams as fuel. By
eliminating the need for extensive upgrading of the gas to meet
standardized quality parameters, as well as avoiding long-distance
transportation of fuels, the system minimizes unnecessary energy
losses and reduces overall costs.
In addition to generating renewable biosyngas, the
gasi昀椀cation process produces biochar as a byproduct, which
contributes to the circular energy system. The biochar not only
provides a means of carbon sequestration, helping to offset
emissions, but also creates opportunities for agricultural applications
by enhancing soil quality. These combined factors enable a local,
circular energy system and independence from 昀氀uctuating global
gas prices.
Furthermore, the gasi昀椀cation system in Kisa reduces the
mill’s dependence on external energy suppliers, enabling the facility
to be more energy self-suf昀椀cient. This, in turn, offers So昀椀del greater
operational stability and cost predictability in the long term.
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Renewable gas production directly at the mill enables
carbon negative tissue production and independence from
昀氀uctuating global fossil gas prices.
A potential negative emissions technology
To fully understand the environmental impact of biomass
gasi昀椀cation, Meva Energy has together with two master students at
Chalmers University of Technology conducted a comprehensive Life
Cycle Assessment (LCA) of its biomass gasi昀椀cation plant in Kisa.
The results are nothing short of promising.
The LCA revealed that the combination of replacing fossil
gas with biogenic renewable gas and harnessing the carbon
sequestration potential of biochar creates a unique opportunity to go
beyond zero emissions and achieve negative emissions. The LCA
study, conducted in 2024 in collaboration with Chalmers University
of Technology is based on the ISO 14040/14044 standards and
veri昀椀es that when the biochar sequestration effects are included, the
gasi昀椀cation process gives rise to a negative emissions value, -6 g
CO2-eq/kWh. This value includes the impact of the entire system
(from cradle to grave) and includes the climate impact from building,
construction and end of life management. Despite this expansion,
the result is still a negative emission value. When only considering
the impact allocated to the biosyngas and exclude the biochar
effects, the process shows a climate impact of 22 g CO2-eq/kWh,
following the energy allocation according to the Renewable energy
directive.
