I asked this same question about reusing the juice from something you've cooked and the answer was yes. It can be frozen and added to gravies or anything else you want to add stock or broth to. The smart way to do it is in ice cube trays so you can grab what you need, but I have various juices frozen in plastic containers that I grab, thaw and dump into something I want my own broth in, rather than store bought.
I've used the juice from pressure cooked ribs for gravy when I grill pork chops and don't otherwise have anything to make gravy with for mashed potatoes. I don't see why you couldn't reuse it to cook ribs in, but it seems like it would be a waste.....
Give us this day our daily bacon.