I live in a northern Ontario town with a pulp and paper mill. The mill churns out a pile of sludge as part of their process, and for the most part this material is burned - it is quite wet and it takes a lot of energy to dry so not much of an energy gain for the mill, I don't think. I can only assume it is most softwoods (and aspen?) going in.
I heard tell there was a fellow some time back who was taking this material and vermi-composting it (with red wigglers?) and that the worms took well to it. I'm not sure if he was trying to produce compost, or sell worms or what. I am trying to assess if there is a way to generate edible insect protein here, for human or livestock consumption. Human being the most ideal.
A pile of questions:
1. will worms eat such a thing? would crickets or meal worms? sounds like BSFL would not
2. do you (human) want to eat red wigglers? can they be dehydrated and powdered into a protein powder kinda thing? how might they taste eating all that wood?
3. do you think there is any way that would be safe if they are eating pulp mill sludge? this might be a sticking point... other waste may be available
4. en mass, do worms generate enough heat to maintain their own temp in winter (-30 deg C entirely likely, -40 C possible)? I heard they previously were actually getting too hot (perhaps also some element of decomposition occuring?) and air had to pipe in to cool them (wouldn't that also speed aerobic decomp?)
5. sources for industrial quantities of worms?
Most of the mills here are paper mills and most of their sludge is cellulose rich, that means it could be turned into fungi growing medium and that would probably give you great mushrooms to sell once you had them tested the first go round.
It can be used in vermiculture and it can be part of a compost operation as well. The one issue would be if it tested caustic, then you would have that issue to work around, which could be done by adding wood chip (more residue from the mill operation?)