It's a continuous process that produces heat and smoke. I'm confused by some of the replies also. Smoldering is a slow, flameless type of combustion that occurs when oxygen reacts with a fuel. It produces heat and smoke. You can't have smoke without some type of fuel smoldering. White smoke generally means your fuel isn't hot enough or is flaming, or your wood hasn't seasoned long enough and is green. Both are a result of smoldering. There can't be smoke if something isn't smoldering.
Smoldering is when the wood never quite ignites.. It produces white smoke. The white smoke flavor is strong to the tongue but suggesting a smoke flavor albeit not a good one. Often called creosote smoke. In electric bullet smokers of years ago, damp wood chips would produce gobs of this white smoke. My big wood burner, with damp, or under seasoned wood will produce that same white smoke. White smoke is a curse on bbq.
You may be able to burn it in a pan like I do with my tubes to mostly keep the ash from ending up in the bottom of my pellet grill.
