Over at the land fill after a hurricane they hauled in thousands of loads of downed tree debris. They dug a long pit about 20/30 feet deep and used a blower to speed up burn times. They laid down a long pipe with holes in it connected to a large blower. It needs to be a very heavy pipe so it doesn't collapse when it gets red hot. The trench acted like an oven keeping all the heat within the trench. They would dump next to the trench then push the logs and brush into the trench with a dosser. They burned 24/7 for weeks.
It all depends on how fast you want it to burn. More air is better then less air. Any air will help.
I had a stump that I wanted to burn out. I used an old shop vac motor and some 3'' conduit to force feed air. I let it run all day and it worked like a charm. It's best to have the air coming from under the bottom.
It all depends on how fast you want it to burn. More air is better then less air. Any air will help.
I had a stump that I wanted to burn out. I used an old shop vac motor and some 3'' conduit to force feed air. I let it run all day and it worked like a charm. It's best to have the air coming from under the bottom.