If you are already seeing larvae dust, the nuts are already nibbled by the larvae, you cannot undo that :( but if you don't mind sharing your food with them, or chomping on the occasional worm, you could try killing them.
I've heard of people using deep freeze. It should kill at least all larvae. The eggs are probably somewhat hardier, but as far as I know, the usual setting of a standard domestic freezer (** or ***) should be enough for killing the eggs too. It can lead to drying out of the nuts, and I don't know if and how you can remove the dead larvae, but soaking them in water would be a good thing to try, as I've frequently seen dead worms float to the top in compotes.
Another thing to try would be high heat instead of low heat. Cooking the nuts through would change them (and their shelf life) a lot, but maybe steaming can work. I don't know how long it has to be before it really kills them though.
In any case, I strongly suggest 1) keeping the suspicious nuts in a completely tight container (I've had worms getting into some standard tupperware containers and similar) and 2) putting up pheromone traps in the pantry, to prevent contamination of further foods.