If you want to go the full sanding route, I would only use a drum sander or an edger if it is a small area. Maybe the 12x18 pad sander would work as well. Your can rent them all. Might even have to go to a progression of grits, like36/80/100/150
I'd try all classes of solvents first though, starting with good old hot water. Paint thinnner, methanol (wood alcohol), MEK, maybe even lacquer thinnner or acetone. LOTS of ventilation and protect your lungs, eyes and hands.
I would never use a belt on a floor, too unforgiving. One second of distraction and you've got a bigger problem than glue.