Alder is indeed a good charcoal for BP. While any charcoal will make useable BP of varying grades and qualities, I’ve read that the “best” wood for making BP is actually cotton, followed by balsa, followed by willow…
“Which charcoal is best for Black Powder? There have been debates over the centuries to this question. Some might answer it by saying the best available, given that different materials were to be found in different geographic locations. Generally, there seems to be agreement that for really fast powder, the following are preferred:
– cotton charcoal
– balsa wood charcoal
– willow charcoal
Charcoal made from cotton is reckoned to be the fastest, followed by balsa wood charcoal, then willow charcoal. Making charcoal from cotton or balsa wood is very expensive. Willow charcoal was the charcoal of choice at the historical du Pont mill at Brandy Creek. One reason for its popularity was its abundant supply in this region.”
- Black Powder Manufacture Methods & Techniques, Ian von Maltitz, pp. 26-27
Reasonable BP has even been made from bags of charcoal you buy for grilling steaks. Since I can’t see your post as I write this, I can’t quote you directly, but you mentioned porosity. Porosity of charcoal for the purpose of making BP is of little concern, as it will be ground up and then mixed with sulpher and potassium nitrate with alcohol in a wet mixure, then caked and screened…
More later… wife calling… brb
Back.. unless I miss my guess, he needs the charcoal for water filtration, not making BP. Best of my knowledge – and I’m no water filtration guru – he would be better off with charcoal made from hardwoods in his area, not softwoods like pine (way too much resin).
Heh.. check this out. Found a sketch of an “Oil drum kiln” on page 103 of the same book… lemme see if I can find an image online to save and post.. it’s perfect for what OP wants… lots of charcoal, easy to build, etc..
Here.. this is pretty close. Instead of one drum, it has two. Pile up rocks or cinderblocks underneath, fill the drums with your wood, seal them. Then build a fire. Where this one shows a formal structure around the drums, the one illustrated in the book shows earth heaped up and covering it. Light your fire, let it get rolling good, then seal it up. Blow town for cornflakes. Come back when it’s cooled down and TA-DAAA! you gots charcoal.
The wicked flee when none pursueth..." - Proverbs 28:1