If you can get it for free, thats great. I have to pay for it. Anyways, I would suggest building some type of collection device for the cooks to pour the oil into. A 55 gallon drum works great, just get an open top and hinge the lid so they can open it and pour the oil in.
Now there are two ways to use wasta veggie oil (wvo) as fuel. You can convert the wvo to biodiesel, or convert the vehicle to run off veggie oil.
To make the wvo into biodiesel, you need to filter the oil down to 10 microns at least, dewater the oil, heat it up and add chemicals to create the reaction, let reaction sit then drain glycerin. Then you must take this new fresh biodiesel and wash and then dry it.
To run veggie oil without converting the oil, you need a duel tank set up. Filter the oil again down to 10 microns and dewater it. Pour this oil into your veggie oil tank. Start the engine on diesel, let it get to operating temp, throw the switch to the other tank and then you will be runnin on veggie oil. A few miles before your destination switch back to diesel and let it clear the lines.
Basically
Biodiesel - No modification needed to any diesel engine, you are modifying the veggie oil
Straight veggie oil - no modifying the oil, no chemicals, just need to install dual tank set up
Anyone looking to get into biodiesel I recommend these two books:
From the Fryer to the Fuel Tank - by Josh Tickell
Biodiesel Basics and Beyond - by William H. Kemp