Decarbonisation Technology November 2026 issue

2 also shows a linear interpolation of levelised production cost between standalone BTL and PTL. The hybrid BTL/PTL value sits below this line, with the gap providing a visual quantification of the potential synergy created by integrating the two line-ups, based on Shell analysis. However, the potential of BTL and hybrid BTL/PTL pathways depends heavily on the reliability of the biomass supply chain. The aim is to convert diverse, variable, and often geographically dispersed materials into a consistent industrial feedstock for gasification. Gasification To date, many biomass and waste gasification projects have faced challenges in achieving technical maturity and successful commercial deployment. Much of the development effort has focused on fluidised-bed gasification technologies, which have relatively few large- scale commercial references and can present challenges when integrated with downstream synthesis processes in industrial-scale fuel production facilities ( Boerrigter, et al ). In contrast, pressurised, oxygen-blown, entrained-flow gasification is a well-established technology with decades of commercial operating experience across a wide range of gaseous, liquid, and solid feedstocks. Shell has licensed more than 200 gasifiers globally, supported by more than three decades of commercial operating experience. Large entrained-flow gasifiers are widely used in power generation, refining, and chemical production, where syngas is converted into hydrogen, ammonia, methanol, and Fischer–Tropsch fuels. For solid feedstocks, commercial onstream availability typically exceeds 96%, providing a reliable gasification platform for large-scale BTL and hybrid fuel production pathways ( Boerrigter, et al). The Shell BTL and Hybrid concepts are based on entrained-flow solids gasification technology, originally developed for coal. Entrained- flow gasifiers require a well-defined, stable powdered feedstock. As a result, biomass and residue streams must undergo pretreatment before gasification. The approach is to convert these diverse feedstocks into a uniform, coal- like powder, often referred to as ‘bio-coal’, with properties that closely resemble those

of conventional coal. This enables the use of established gasification technology while improving process reliability, efficiency, and scalability ( Boerrigter, et al ). Making biomass suitable for gasification The BTL opportunity is significant, but raw biomass materials are not naturally suited as feedstock for large-scale gasification. Biomass and residue materials cover a wide range in composition and physical properties. That variability and the intrinsic properties create challenges in handling, feeding, and process stability. The practical requirement is to turn diverse biomass streams into a consistent, energy-dense, and flowable material. For BTL production, this means preparing a bio-coal feedstock that can be reliably milled and stably pneumatically fed into a pressurised solids gasifier. This preparation chain typically includes mechanical pretreatment by size reduction and removal of inert materials, such as stones, that would hamper downstream processes. After drying, the biomass is torrefied to produce a homogeneous coal-like material with improved grinding properties. The torrefied material is subsequently pelletised, yielding pellets with high durability and high bulk density. The pellets can be stored, handled, and transported as a commodity. More importantly, pelletisation also improves the quality of the material after milling (i.e. higher bulk density powder and improved particle shapes). As part of the gasification process, the pellets are milled using standard coal milling units to produce a well-defined fine powder. The powder is pressurised in lock hoppers to the gasifier pressure and pneumatically conveyed into the gasifier using CO2 as carrier gas. Each step has a role to play, but torrefaction is required to change the physical properties of the biomass, helping to increase energy density, improve grindability, and create a homogeneous gasifier feed. This is where the collaboration between Shell Catalysts & Technologies and Yilkins is focused. Shell assessed multiple torrefaction technologies and carried out feedstock screening and process optimisation trials, including tests of the flowability and pneumatic feeding properties of torrefied products. As a result, Yilkins’ technology