Good morning
For smelting WW any heat source and any old yard sale cast iron pot or scillet willl do the trick.
I do my smelting on an old Coleman 2 burner camp stove and a stainless pot from a yard sale. I still have the old skillet I started smelting with and still iuse it for small batches.
Here in Peru I use a table top propane stove with a heavy rack I lay on top of the origonal light weight grill work.
I know a couple fellers who use a wood fire to smelt large batches or lead.