How can biofuels be integrated into petroleum refineries?

Biofuels integration options: Co-processing - blend bio-feedstocks (vegetable oil, animal fat, pyrolysis oil) with petroleum feeds in existing units. Hydrotreating co-processing: fatty acids converted to paraffins (renewable diesel). FCC co-processing: bio-oil adds oxygen, affects product distribution. Standalone renewable diesel - dedicated hydrotreater for lipid feedstocks, produces drop-in diesel. Higher hydrogen consumption than petroleum HDS. Bio-jet - hydroprocessed esters and fatty acids (HEFA) meeting jet fuel specifications. Ethanol integration - ETBE production for gasoline blending using existing alkylation/MTBE infrastructure. Challenges: feedstock variability and availability, higher hydrogen demand for deoxygenation, modified catalyst requirements, and supply chain logistics. Economics depend on feedstock cost, carbon credit value, and product premiums. Many refiners adding renewable diesel capacity using existing or modified infrastructure.