My husband uses it to make fuel for his car ("sort of" biodiesel - google waste vegetable oil and you'll see what I mean) and recycles it that way. I would have thought it would be very slow to break down in the compost heap and might very possibly be a fire hazard or attract vermin. To get it into a useable state, my husband has to filter it, heat it so that the water sinks to the bottom and then put it in a centrifuge, so that gives you an idea what sort of punishment it will take and still stay "oily"! Commercial kitchens have to pay to have their waste veg oil taken away and that's probably why!
Sorry I can't be more help...