Colour me stupid possibly, but could you use a jet of air to blow the sawdust powder into a combustion zone? Like a Babington burner, but with the wood dust in a hopper above?
That’s exactly what I am hinting at. There is a bit of pneumatic equipment called an air/material transfer nozzle, which is used to blow materials (like plastic granules for injection moulding machines) between the bulk container and where they are needed. It works a little like the venturi which used to be used to draw liquids up from a can and then atomise them into a fine spray. The perfume sprayer was an example of this. They also produce up to 10″ Hg vacuum, and this is what provides the “suction” for transferring granular materials. This is the principle of the ejector, where a high pressure blast of air from a nozzle is used to drag along a significant volume of low pressure air and produce “suction” perhaps this is partly the effect on the babington burner air jet.
My thought was that it’s such a nuisance and expense (time + money) to have to convert a potential fuel to another ‘structure’ as it were. If wood dust is a worthless waste product, they might even pay you to take it away.
Well, actually, I’m not really interested in processing wood waste. As I said before, I’m looking at other types of biomass, which is a lot more plentiful — crop residues like corn cobs, marsh hay, cattail leaves, tree leaves in the Fall. I was also thinking of scrap paper, but I found out that’s bringing $100 a ton now, more than you could get for pellets wholesale. But you could go around with a truck the night before trash pickup and get tons of paper and cardboard — it’s set aside for recycling in most cities now. Run it through a hammermill (shredder/chipper) and pelletize it. Wouldn’t be too good to grill over tho.
Have you ever heard of Fire Cookies? I knew this crazy guy in Colorado who was making these things. Used them on his grille for cooking hamburgers, etc. Take strips of non-glossy newspaper. Put in blender with water. Turn into a paper pulp again. Press this fluid / mass in a potato ricer to get the water out. Set the “cookies” out in the sun to dry the rest of the way. Arid in Colorado. Take a handful of these fire cookies and place in the grille. Light them with a match. Notice that I DID NOT say use charcoal lighter fluid. Stand back and in about 5 minutes you are ready to grille your hamburgers. Objection number one: Oh those nasty inks will give you cancer! Not!…soy inks are used now. Objection number two: It will stink. Not! Objection number three: These are too much trouble and are too hard to dry out. Not! The list goes on. I made a few of these myself and they do work pretty damn well. Try it, it’s easy. You could dry them with a Babington burner set up for the task.