Good thinking.Electric, oil-filled radiators are probably the safest, easiest, and least-expensive bet for you. They plug into a normal 110 outlet and heat very well without any flame or exposed element that could ignite the dust. You can get them at most Home Centers and even Target or Walgreens sometimes during seasonal promotions. For more expensive/permanent solutions, there are more expensive radiant heat options. I would stick with radiant heat as opposed to any forced air or directly-exposed-to-air element heat. Even with filters, the filters clog quickly and reduce your heating efficiency.

I HAD A WOOD SHOP BUILT ONTHE SIDE OF MY
GARAGE. FOR HEAT I PUT IN A PROPANE WALL FURNACE THAT GETS IT'S CUMBUSTION AIR FROM THE OUTSIDE AND IS SAFE IN A DUSTY AREA.
I GOT MINE FROM WW GRAINGER. THEY WILL ALSO COME IN NATURAL GAS.
IT DOSEN'T SEEM TO BE EXPENSIVE. I KEEP THERM. TURNED ALL THE WAY DOWN AND IT STAYS NO LOWER THAN 45 DEGREES.

JERRY