Decarbonisation Technology - November 2024 Issue

Feasibility study: Repurposing a European refinery for circular chemicals

A European refiner wanted to explore the potential to produce circular * and/or bio-methanol (bio-MeOH) * , dimethyl ether (DME), and methyl tert-butyl ether (MTBE) while using existing equipment. Shell Catalysts & Technologies evaluated three options: • Option A assessed switching gasification feedstock from heavy residue to imported pyrolysis oil. This option would require investment in new pyrolysis oil import infrastructure. However, existing gasifiers and infrastructure would remain unchanged. • Option B evaluated switching to imported refuse-derived fuel (RDF), which would require investment in new gasifiers (tuned to the feed type) and new RDF import infrastructure. • Option C considered two gasification feedstocks: (1) chemical residues sourced from neighbouring chemical plants and (2) municipal solid waste, with the option to switch to wood according to waste availability. This option would require investment in chemical residue and RDF import infrastructure and new RDF gasifiers that would work alongside existing gasifier units.

Heavy residue

Existing gasiers

Gas cleaning

Methanol synthesis

Current

DME MTBE

Existing gasiers

Gas cleaning

New pyrolysis oil import infrastructure New RDF import infrastructure Chemical residue import infrastructure New RDF import infrastructure

Methanol synthesis

Option A

DME MTBE

New RDF gasiers

Gas cleaning

Methanol synthesis

Option B

DME MTBE

Part of existing gasiers

Gas cleaning

Methanol synthesis

DME MTBE

Option C

New RDF gasiers

200 kt/a of MSW with the option to switch to wood; 160kt/a of chemical liquid residue

Significant upside potential Option C provides the most upside potential and return on investment when considering Capex, cost of gasification feedstocks, and potential revenue from circular and bio-methane. Yield potential: 380 kt/a of mixed methanol • 20% circular methanol • 30% bio-methanol • 50% methanol derived from fossil-fuel-based waste ** • Methanol can be used as sustainable fuel or processed into MTBE or DME according to market demand. * Circular methanol is derived from plastic waste; bio-methanol is derived from organic waste, including biomass residues from industrial processes. ** Fossil-fuel-based waste includes liquid chemical waste streams from nearby chemical plants.