Hi Brian , Yes they certainly would make very good 5 minute lasting Tuyeres or if you could have them self feeding down your pipe as a sort of self replenishing nozzle , might work , give it a play on the weekend and see .
I will try and get some pics of cyclone or even a small video uploaded of it collecting very fine carbon dust and show you how much will pass through on strong suck , the inlet/outlet pipe dia is only 25mm id but should scale up .
All the best Dave