Do not mix the two oils
UCO is a lipid for transesterification under RUCO. Used engine oil is a hazardous lubricant stream under CPCB EPR. Mixing them ruins both offtakes.
Re-refining
Vacuum distillation and hydrotreatment can yield base oil for new lubricants. That is the high-value circular path when the lot is clean.
Energy recovery
Some authorised units recover energy. Informal burning in a furnace is not this. Authorisation is the line.
Why dealership stories mention biofuel
I Am Renew and related coverage describe Globe Toyota recycling engine oil with BioTradX toward responsible downstream use. Your workshop still needs a licensed recycler on the contract, not a slogan.