Preem becomes part owner of SunCarbon and plans to build an additional lignin plant for biofuels
Type of post: NEWS.
SunCarbon
is a Swedish company whose vision is to utilize forest industry by-products for
the generation of renewable fuels. It was founded by three companies with
experience in the fields of chemical pulping, membrane filtration and catalysis
(KIRAM, Hulteberg Chemistry & Engineering and Arkell Innovations).
Combining their expertise has enabled the
creation of the SunCarbon concept and is the starting point for valorising
lignin (by-product from pulp and paper mills and can be extracted from the
black liquor). The final product obtained this concept is a depolymerized
lignin-rich oil, which can be sent to petroleum refineries for upgrading to
motor fuels. The oil, raw material for HVO,
is a renewable and aromatic product with low carbon footprint and excellent LCA
results. The capacity of each potential plant is 10-50 ktons of fuel products
per year and in the Nordic countries at least 10 plants can be constructed.
Recently, Preem (Sweden's largest fuel company)
and Sveaskog became shareholders in SunCarbon. The strategic partnership with
these companies is an important step forward for the market introduction of the
lignin valorisation technology. Also, Preem has announced plans for an
additional lignin plant for biofuels. The new plant is expected to produce
about 45,000 tons of lignin per year and be operational in early 2022. Preem
is already collaborating with RenFuel and Rottneros on constructing a lignin
plant for biofuels at the pulp mill in Vallvik (Söderhamn, Sweden). The
plant is expected to produce about 25,000-30,000 tons of lignin per year and be
completed by 2021.
Press release: “Preem
blir delägare i SunCarbon – planerar ligninanläggning för biodrivmedel”, 2/5/2019.
85% of all biofuels on the Swedish market are
imported. With increased utilization of lignin from national mills, this figure
can be reduced considerably. Preem's ambition is to produce 3 million cubic
meters of renewable fuel in 2030. This corresponds to the total volume of fuel
that Preem sells on the Swedish market today. The compnay has an aggressive
investment plan for Sweden with several different production plants in planning
phase. But, in order for the investments to become reality, the right
incentives are required for increased domestic production of sustainable
bio-raw materials.
SunCarbon concept
Lignin is extracted from black liquor and
processed in multiple steps to a depolymerized lignin-rich oil. The SunCarbon
process can be divided to three different parts (all situated in the pulp and
paper mills).
Figure 1. SunCarbon concept (taken from the company
website)
1. Membrane separation
Lignin is separated from the black liquor using
a membrane separation step. The membrane will fractionate the lignin in a
retentate and a permeate stream. The lignin-rich retentate stream will then be
processed further in the hydrothermal treatment. 10-25 % of all the lignin
produced in the pulp and paper mill can be recovered without impacting the
chemical recovery boiler operation.
2. Hydrothermal treatment and purification
The retentate stream is treated in a thermal
catalytic cracker at sub-critical conditions. The resulting lignin mixture is
processed with additional steps including acid wash and solvents to remove ash
and residues. After additional desalting the resulting product is a
depolymerized lignin-oil, ready for transport to a petroleum refinery for final
hydrogenation,
3. Process integration
The lignin is extracted with several major benefits
such as increased pulp capacity and the possibility to fully or partly recycle
the permeate stream from the membrane separation and use it in the green liquor
preparation step. Through careful understanding of the pulp and paper industry,
the material and energy efficiency achieved is high without compromising the
delicate chemical balance of the mill.
