Just spitballing here, can a OWB be connected to a heat exchanger to heat a cabinet shop? Ultimate idea would be to use ALL the sawdust and scrap to feed the owb.
Sawdust, being a dust, can be somewhat explosive given the proper conditions. My friend has put wheelbarrows full into his owb after planing down all of my oak trim, it certainly burns, nice and hot, but not for very long, and is pretty smoky. Scraps on the other hand most definitely, although they will be a small pain. As far as a heat exchanger goes, most certainly, all owbs have 1 input and output line, most (like mine) have 2 for heating house and another for a shop or garage, and I'm sure there's a few big models with 3 or more. All you need is a pump good line and an exchanger.
My dads OWB eats that stuff daily. Ive had to tend it the last couple winter due to his health. I put a couple layers of slabwood in the bottom on raked forward coals. Then 1 or 2 large rounds and shovel it full of sawdust, bark, chips, and scrap wood. We have an advantage that we can store 20+cord inside and push it forward with a large loader. Works well and gets rid of a lot of waste wood. The first hour of the burn on dust chips and bark really makes a lot of gas. Ive reopened the door 10 minutes after loading and get a pretty good WOOOOF out the door. Load it with that stuff and leave it. Don't check the fire ,, it will surprise you.
Yes, go ahead with your spitballing! Only thing is the sawdust will not burn as well as you may think. It'll burn but.... Compare it to ripping pages out of a magazine and throwing them into a fire for burning as opposed to throwing the whole magazine into the fire.
I'm a contractor and I have thrown shovel loads of saw dust and scrapes into my Woodmaster. Just to get rid of it instead of filling up garbage cans and bags. That said do not count on heating much with it or any decent burns. It takes wood. Most OWB's like a bunch of wood too. I have shoveled wheel barrow loads of saw dust and small chunks (as in very small) along with bigger scraps into mine over the years just to get it gone. It will burn fine but very fast and I always had a fire already burning. I wouldn't shovel saw dust into a stove inside though. Too messy and not worth it for many reasons. Dave summed it up pretty well with the pages of paper. But as I did just to get rid of it I have found it is fine doing so but you really will not run any OWB on saw dust and scraps alone heating much of anything. Hope that helps. Another note I have burned anything from fine saw dust to root balls of trees in the Woodmaster. It will burn whatever you can get into or thru the door. Skids, boards, etc: Never burn any garbage or junk though. Just wood, paper, some cardboard and reasonable stuff like that. I would load my dump truck a lot with wood cut offs from framing jobs etc; and save dumpster space or a trip and fee to the dump and get free heat in that fashion.
Portage and Main and one other make a biomass owb that has a sawdust/chip bin with an auger into the owb?
Possibly but I am not familiar nor seen one but they might make them. that's worth a Google and some reading. I know Woodmaster had a very big model for commercial use that had a door large enough to load skids into it with a tow motor fork truck.
In a perfect world I'd set this up to heat a 8000 sqft cabinet shop and my 2400 sqft shop. Both shops are next to each other and the sawdust bin is in the middle. Biomass owb would go next to the sawdust bin. Not sure on the heat exchangers? Here's the P&M owb; The EnviroChip Series - Portage And Main Boilers
The old Woodmaster 5500 rated for 10,000 SQ FT does my barn, house, hot water and garages. It is a unit that has multiple ports for multiple buildings. I will look at the thread you attached.
I would need a few of these; 210k BTU Unit Heater Outdoor Furnace Boiler - Variable Speed Fan - Water to Air Heat Exchangers
Unicorn I have two of these H2O to air exchangers identical to the pics above. They come in different sizes for different size spaces obviously. How much are they selling for now? Most of these OWB's use the same units and parts etc; such as Pex tubing, these air handlers, Taco pumps, fittings and all so shop around for better deals and prices. What I am saying is the only brand / model specific parts are on the OWB's themselves like their control boards and electrical parts and stuff but many of these may be made at the same places also. The air handlers can run on their own house stats and the fan kicks off and on to the set temp on your stat. I run my Woodmaster and air handlers on zoned stats. 6 stats altogether. For example I have one of these in a two car garage and they are great for an all-in-one self contained unit. I also have one in the central HVAC system (heat pump) plenum and can heat thru my forced air and duct work. This one does not have the built in fan like pics above as it uses the blower on the HVAC system. It is just an fins and tubes unit that the water flows thru. I also did some radiant floors and feel that is the best overall but costly and not practical in many situations. One issue with the radiant floors is it takes awhile to get all the thermal mass up to temp if you start from cold. Much longer than forced air but it also heats much longer after you let the fire burn out. The ones in the garages and a shop area heat those areas to whatever I want but I usually have them dialed down some to say 55* - 60* which is fine for those places. If I want to be out there doing stuff and want it warmer I can crank the stat up. One thing I will say is the all-in-one H2O air handlers fans are a little loud but perfect in a garage or shop. I wouldn't want one inside the house if that helps. Really not loud at all in the right spaces. The sound is from the fans and can be toned down. Where I mounted mine I did so with thick rubber bushings which helped. I still have not looked at the previous link and read up on the Portage and Mains yet because the Time Warner cable < (can't stand them but I have limited options out where I live). The internet here has been not working well for days and running too slow. I'll check it out because this AM it seems to be functioning normally again. BTW the louvers on them are movable and adjustable so you can do what you want there for air direction. I mounted mine low and aimed the louvers down since warm air rises. Worked out well.
I think I paid about $400 for mine but that was the fall of 2004 and smaller units. I'll have to look at what they are....but I have to run now. I'll check back in though.
There are some folks doing exactly that in Virginia. Check out this video they made. HeatMaster MF10,000e Long Island Lumber Testimoni…:
