Driveway upkeep

I would like to know how to remove old, already dried up oil stains from my concrete driveway? Thank you

1) There are enzymes you can buy, that will break down the stain.
2) Sandblasting will work.
3) Pressure washing might work.

rub in with your feet speedy dry that you get at auto part stores picks up oil and grinds into concrete looks much better.might have to put a couple of applications depends how bad oil stain is. works good, looks like cat litter stuff, I think its mostly clay chips.