Thermite reaction: aluminum POWDER + iron oxide + 1200C = dangerously hot and too bright (eye-damaging) reaction/fire. (Also leaves behind once-molten iron [from the iron oxide component], which is why a termite grenade up the snout of an artillery piece renders it irreparable under field conditions.) You COULD do it (As noted by nodh, magnesium will supply the ignition temp.), but why?
Having picked up the results

rolleyes

from literally hundreds of wood fires, I can tell you that aluminum, pots, pans, cans or foil will not burn at wood fire temps - just melt. I doubt that turning it into a powder will change that since wood, burning about 233C, supplies heat well below the ignition point of aluminum (over 600C).
I think the sparks from a "fire steel"/ferrocerium rod are also not hot enough, at about 475C, to ignite aluminum.
In any even, why bother? You won't produce aluminum power in the field. If you are going to carry something into the field, petroleum jelly-treated cotton lights with a match, butane lighter, or ferrocerium sparks, and burns a relatively long time = better succcess in lighting your fire.
But if you have a 155mm to disable . . . . .
