ERTC Newspaper 2022

ERTC 2022

Sustainable aviation fuel: prepare for take-off!

AXENS

Despite the unprecedented drop in global air traffic due to the Covid-19 crisis in the past years, passenger numbers and cargo volumes are anticipated to increase in the coming decades. Greenhouse gas (GHG) emissions from aviation contribute to 2% of total GHG emissions, with just over 600 Mt of CO₂ production in 2020. While a range of solutions, including technical, operational, and behavioural, are required to reduce aviation emissions, it is recognised that liquid fuels will continue to be the dominant fuel for air travel through to 2050, and there are many technology options to transition from fossil-derived jet fuel to sustainable aviation fuel (SAF). SAF is an alternative to fossil jet fuel and a promising solution to decarbonise the aviation sector. It is produced from either: • Renewable or waste-derived bio-based resources that meet sustainability criteria depending on the source, such as renewa- bles oils and fats, lignocellulosic biomass, wastes, low-carbon intensity (CI) inedible starches, and sugars • Captured carbon dioxide combined with green hydrogen (produced via the electrol- ysis of water using electricity from renew- able sources (so-called e-kerosene) SAF is a drop-in fuel, meaning it can be blended with traditional jet kerosene (cur- rently up to 50 vol%), and the blend does not require any equipment change, special infrastructure, or modification of the sup- ply chain, limiting supply-chain investment requirements. According to the IEA, SAF currently accounts for 0.1% of global jet fuel con- sumption: producing SAF today is currently more expensive than producing fossil- based jet fuel. A combination of consumer pricing, regulatory, and incentive pro- grammes is therefore required to expand SAF production, regardless of the pathway. All roads leading to SAF Among the seven pathways currently cer- tified under the ASTM D-7566 specifica- tion for synthetic kerosene to be blended into Jet A1 pool, Axens provides de-risked technology for the three main pathways. Each of these pathways can significantly reduce fuel lifecycle GHG when compared to fossil baselines, with reductions well over 90% possible when utilising advanced cellulosic feedstocks and/or green power: Vegan ® : Hydroprocessed Esters and Fatty Acids (HEFA) pathway: Vegan is a flexible solution to produce renewable die- sel and SAF through the hydrotreatment of a wide range of lipids (renewable vege- table oils and animal fats). This technology allows producers to effectively address environmental regulations and sustainabil- ity targets, and secure energy diversifica- tion with drop-in premium quality products. Vegan technology includes a hydrotreat- ment (HDT) section and a hydroisomeri- sation (HDI) section. The HEFA pathway

Atol®

2 Oligomeri s ation

Dehydration

Hydrogenation

Fractionation

Sustainable aviation fuel

Any e thanol source

Futurol®

Figure 1 Main sustainable aviation fuel pathways

V egan ® HVO

Lipids Fats, veg oils, UCO, etc.

BioTfuel® Gasi fi cation + Fischer - Tropsch (FT)

Gasel® Fischer - Tropsch + upgrading

Lignocellulosic biomass Wood residue, agriculture residue, energy crops

Sustainable aviation fuel

ATJ Alcohol to J et

Futurol™ 2G enzymatic conversion

2G ethanol

Green H, carbon capture, waste, low-Cl, inedible starches and sugars

1G/2G alcohol

Figure 2 Alcohol to Jet pathway

offers the possibility to revamp existing hydrotreatment units and turn them into HEFA units to produce SAF. Gasel ® : Fischer Tropsch (FT) pathway: Gasel technology converts synthesis gas (H₂+CO) from various origins – biomass, captured carbon oxides – into a flexi- ble slate of ultra-clean liquid fuels (XTL), including SAF. This Fischer-Tropsch route is commonly accepted as one of the most promising mid-term solutions for the pro- duction of alternative fuels and petro- chemicals, including biomass-to-liquids (BTL) and e-fuels. It includes syngas puri- fication and Fischer-Tropsch synthesis and product upgrading. did you know Axens is uniquely positioned to bring de-risked technologies to BioTfueL ® : Gasification pathway: BioTfueL technology unlocks SAF and advanced bio- fuels production from energy crops and agricultural and forestry residues (includ- ing wood industry residues) via a ther- mochemical pathway. This technology enables access to a wide range of biomass three of the primary pathways: HEFA, ATJ, and Biomass to Liquids via Gasification and Fischer-Tropsch?

and positions itself as a sustainable alter- native to vegetable oil and food-based renewable fuels. Axens is the only licen- sor offering a BTL solution from biomass to liquid. It relies on a four-step process: pretreatment, gasification, syngas condi- tioning, and Fischer-Tropsch synthesis and upgrading. Ethanol to Jet pathway: Ethanol to Jet (ETJ) is the process by which 1G or advanced bioethanol (2G) is converted to SAF via different steps: dehydration, oli- gomerisation, hydrogenation, fractionation (see Figure 1 ). This differentiating technol- ogy bundle approach utilises already com- mercially proven processes, with over 100 homogeneous and heterogeneous refer- ence units, 70 hydrogenation references, and four dehydration references. Futurol ® : Enzymatic conversion path- way: Futurol converts lignocellulosic biomass from from energy crops and agri- cultural and forestry residues (including wood industry residues), into cellulosic eth- anol (advanced bioethanol). This cellulosic ethanol can then be converted to SAF with the ATJ process described above. Futurol relies on a four-step process: pretreat- ment, biocatalysts production, hydrolysis and fermentation, and products recovery. Futurol was selected by INA, in Croatia, to produce 55,000 tonnes, equivalent to 70 million litres, of advanced bioethanol in synergy with green energy production. Combination of Enzymatic conversion + Alcohol to Jet pathways: Combining Futurol and the Alcohol to Jet processes provides the possibility of producing ultra- low CI – or even carbon-neutral, advanced SAF from lignocellulosic biomass. This chain has many advantages, including:

 A two-stage investment plan to either produce advanced bioethanol first (with Futurol), then subsequently build an Alcohol to Jet block  To produce SAF from low-CI, 1G etha- nol (with ATJ), decarbonise the SAF over time with the introduction of advanced bioethanol  Utilising a ‘hub and spoke’ approach by building multiple small Futurol plants near feedstock sources that all feed a central- ised ATJ plant that captures economies of scale. These advantages make the ATJ pathway unique in today’s continuously evolving environment. Conclusion Many different types of technologies and pathways are now available to produce SAF, and Axens is uniquely positioned to bring de-risked technologies to three of the primary pathways (HEFA, ATJ, and Biomass to Liquids via Gasification and Fischer-Tropsch). Each pathway has dis- tinct regional feedstock-specific, econ- omies of scale and techno-economic advantages, with each one having a role to play depending on the individual pro- ject context. Meeting the demands of the aviation sector will likely require the imple- mentation of multiple project pathways, including those listed here. Axens can per- form feasibility studies to select the right pathway(s) with the right business model in order to come up with the most optimised solution to fit any need. The common threads running through these technologies are flexibility, reliability, and the realisation of decades of technology development, demonstrating that Axens is ready to meet the challenges of scaling up SAF capacity in the coming years.

Contact: Yvon.BERNARD@axens.net