You might try adding a couple of split pieces of wood on the fire, about 6" apart, let them catch fire, burning real well, then add coal in between and alongside the splits. don't cover and smother the fire, it takes some finess, but I found that the big wood flame tended to burn up the volitiles in the coal.
If you want to experiment, adding some over the fire combustion air [seocndary air] will help burn off the volitiles from the coal when it is first heating up. T But this secondary air needs to be warm or hot, preheated by the coal fire so that when added to the smoke coming off the coal, it will promote combustion , not cool down the smoke, preventing combustion. It's a difficult combustion to creat, but just about eliminates the smoke from fresh coal.
I think Steinkebunch had a video of secondary air burning off volitles, and how he made the preheated air mechanism.
Good luck, let us know how you are doing.''