It would result in a large elliptical “hell hole” where the gas goes into the exit pipe. It looks like to me, the holes in the flute would have to get larger going from where the air enters to the other end. Probably substitute the screen grate with maybe a solid flute again with the nozzles openings going from large to small as they go from one end to the gas outlet end… I don’t think a screen grate will pull a vacuum all the way from the gas exit end to the other. $.02 TomC
Hi Tom, how about air going into flutes from both ends of the pipes at the same time. And gas exiting out of the lower pipe from both ends or directions, this will give it a even flow in and out of pit of hell. My 11/2 cents idea.
Bob
Hi Kristijan, this is why I was think it needs a restriction zone area. So it has the power of being able to speed up the air/gases which converts over to frequencies to do what we call the cracking of gases, being it in the form of H2O, CO2, or bio matter, wood, tars, ect… So by not using a restriction zone of some kind, we are limited to just using good quality charcoal.
I think with this design of having a restriction zone will give it more flexibly for fuel qualities like the use of woodchips and the like.
One important thing in the design is the weight factor for smaller vehicles. I can’t put a 200 pound plus WK gasifer on the back bumper or in a trunk of a vehicle.
So the question is, can we make something different that can basically do the same thing. My thought for fuel is this. Lazyman charcoal in a fire pit. Cool it course grind it with a shovel screen it, everybody can come with this simple method. Mix it with wood chips with moisture in them. That’s your fuel simple. If the fuel sit for any length of time the chips dry out because of the charcoal moisture absorbing abilities. Charcoal will also keep the stored mix of wood from rotting or decomposing. I hope I am making some sense here. I really like the rocket fuel combination that you and I have been using. This gasifer is a down draft unit, so lets try to get the most out of it.
Which brings us to the flute tube nozzles, they need to be built stronger now that they are being exposed the fiery furnace of hell itself. Normal tubing will not work unless it is supported by brackets under them. And the flute tubing can not be that close to the gasifer container walls. Ammo boxes are not designed for this, but we can beef it up some by placing a heat shield behind the nozzles.
Okay I Know this is not super simple KISS design but hey I am going to have this on the back bump of my Subrau. In the tree hugger State where I live, with some of the highest regulations of the United States.
So I am going in the direction of flexibility in fuel, and still try to use this flute nozzles design. May be this could be built into a wood gasifer with a touch of the WK concepts with it. Now that would be cool. We are only limited by our minds on how we think. All things are possible for those who believe that it can be done.
Bob
Tom, l agree on the first part. Its why l proposed the flute penetrating out trugh both sides of the vessel. Just like Bob sayd. However the problem with the flute is the opposite; the air rushing in, slaming the end wall (in case one part of the flute is blocked and the air intake is only from one side) causes the last few nozzles to blow harder. Its why l started gradualy lowering nozzle diameter toward the end plug.
The other thing, about the grate not sucking evenly, l dubt its gonna be a problem. As long as the cilinder of expanded metal or perforated steel is of sufficiant diameter the flow shuld be even. After all, its the same principle as a sak filter. The coat of dust is always even on the surface.
Bob, again, there is a restriction on the system. Just not your clasical “lmbert style” metal ring. The naturaly forming “ashcone” will form toward the gas outlet channeling the gases to a taper towards the gas outlet. Exactly like a WK.
I proposed a tighter gap for a char/wood mix just as a precaution. Just as with the clasical Imbert specifications, we need to follow some rules here. You cant design a oversized oxidation zone with a lmbert no matter how tight the restriction is, they must be in sinc with each other.
I like the lazy mans charcoal idea! A nother great advantige of a downdraft charclal gasifier is its not dependant on fuel size so much as a updraft. I dubt much grinding wuld be nessesery. Dump a bucket of water over the pit, just to steam-suffocate the burn, shovel in a barrel an screen out the ash.
Bob, just one more thing on CO and H2 production and restriction. I was given a chemist book as a gift from ww2 erra. Its old but inorganic chemistry was known well at the time. Anyway, it says carbon (charcoal) burns (oxidises) with oxigen to form CO2. We all know that. But once you cross a certain temperature barrier it starts skipping a step and burns straight C + O2 → CO. What this means is if we run any gasifier at a high enaugh temperature it will not have that clasical oxidation zone–>reduction zone transition. It just becomes one reduction zone the size of oxidation zone. Hope it makes sence.
In other words, the hotter you go, the smaller the glow zone is for the same amount of gas produced.
The resaults from my last MB gasifier confirm this. The “glow zone” on it was just roughly the size of a 4 pound mellon yet l was driving it to 75mph. Yes, the gasifier started to overheat and melting the ash but the gasifier never got in to heater mode!
Okay Kristijan, the ash cone I see that and the gases/air speeding up at the end of the cone, no problems there in the down draft mode. I see no reduction area before the grate pipe with gases leaving. The ash/charcoal will just pack up around the pipe or is this the reduction area now like in a grateless system? Okay I am see it now. This is really KISS. Keeping It Silly Simple.
Will the ash cone have to be added be fore the original start up? Or just form naturally through use?
Bob
Bob, all this exposure to the spirit of inovation makes my fingers itchy… the grinder and welder are close… its a dangerous situation
A few more stimulay and im gonna build it my self haha
Well l think it will work just fine prefilled with engine grade char. Ash shuld build up later and fill the gaps.
Yup I know what you are talking about Kristijan. I am hoping for warmer weather here. Winter has moved in to my area. It is snowing right now. Cold!!!
I need to find the right ammo boxes first.
The nozzle pipes being attached to the heat shield plates, with ash between the shield plates and the ammo box walls should be good enough heat protection. I am sure I can build it so it will just bolt in to place, no welding at all.
Sorry @Wayne I should of warned you before I mentioned the bad words. It is s@#%*&g right now. C#@D!!!
Bob
Sorry but I am trying to catch up on this project. What is this ash cone you are talking about? My interpretation of “ash” would be— charcoal that has given up all of it’s carbon. That is almost “nothing” in theory. In our “regular” gasifiers, ash in reality has a large quantity of carbon still in it.
What are you going to make the grate out of— specifically. You both are ready to start building, so what exactly are you going to us. It has to be heavy enough so that it doesn’t burn up like fine steel wool. How big are the “screen” holes-- they have to be large enough so they don’t plug with ash/char and yet small enough that air/gas will not readily pass through it. I don’t get it. In my drawing the gases are flowing to the end of the exit pipe, almost ignoring the screen. My thought would to be like an Imbert, upside down. Have a row of nozzles that protrude through the ammo box and you connect them to a common manifold. I see no resemblance of the screen to the sock filter — I could draw a skiz of the sock verses the screen, but until I understand this screen grate better, I’ll wait. TomC
Okay Tom, let me try to explain this. With my much bigger cross flow charcoal gasifer I built. I had my nozzles and a pile of charcoal. No reduction cone, no grate, no screen. It did have a exit or dropping area for char/ashes the gases to separate going out the gasifer. It worked great, until the charcoal became low because of not flowing downward to the nozzles and formed a worm hole. It made good gas to run my genset with it loaded up.
Now in this new idea not proven yet. We will have a long rectangle shape ash cone going to the gas exiting pipe with a screen around it.
The ash cone is the reduction zone that will naturally form as the gases head to the exit pipe, that will automatically do self purging as the gases leave the gasifer. Pre loading the gasifer with course charcoal in the bottom will help keep the purging like in a grate or a grateless unit like mine was. Charcoal only unit. I have now change it for some other testing like adding wood chips to the mix. In fact I can use my unit to test this new concept out.
Not everthing has been try under the sun in the world of gasification. If it did, it did not get published and was forgotten about.
To do the the impossible is to just figure a way to do it.
Bob
I believe the grate will be made of expanded metal screen. You know the common stuff with diamond shape holes. I replaced the grate in my bottom draft wood stove with stainless expanded and it has held up well for many years.
I’ve been observing but unable to comprehend yet.
First of all, I want to build a fluted inlet for a charcoal gasifier to run a 15 hp engine. Are you saying with the fluted design, the charcoal doesn’t need to be a certain size? Also, for a smaller engine, how far apart can the holes be?
Hi Bill, I am hoping we will be able to use charcoal that is bigger than popcorn size that would be great, but right now it is the size of popcorn and smaller. That is what I make with my charcoal grinder. The reasons I would like to see it with larger charcoal is it will let ashes and the charcoal gases pass through it with less vacuum pull. This is my thinking anyway, it will let the ashes settle out into the bottom of the gasifer ash ammo box and get trap there. We need the ash cone in the top below the nozzles all the way down to the gas exit pipe screen. After the ash cone is established you will not want to remove it when you clean the ash out of the bottom part of the gasifer. Or the whole building up of the ash cone as to be established again. When it is running the ash is continually moving making its way down and more is building on the top part. Just like the charcoal does this is a common internal movements in gasifers that have this cone ash protecting it, eventually it will pack down hard making a hard cone shape.
I do not like to mess with the ash in my gasifer after It gets establish. This is what I am working on right now. There is no restriction plate to hold things up. I might have to have a screen at the top of the ash drop ammo box to help hold things up. This is new uncharted design in the world of gasification.
Bob
In the ones Im building now, size can very. The smaller the pieces the more fuel you can fit in the machine so longer run times. Too small I think the gas quality is not quite as good, too larger the gas is not quite as powerful.
I now try to get somewhere in the middle without putting too much work into breaking up the fuel. I use a 55 gal drum to store the fuel in. So I just use a shovel to chop up the top layer and then shovel that layer out onto an inverted screen to get the dust out. The repeat. This screen dumps into a 5 gal pail and when it is full, I replace it with and empty and re screen it and then it is ready to run.
What they are proposing is very like the units I am building except Im using a single jet at one end. I shroud the jet with a pipe half couple so it is not touching any charcoal. I have yet to see any form of deuteriation. Doing a test now with a slightly longer jet to see if it will melt.
Hi Matt. Even if I put a little to big of pieces into the gasifer at the bottom I think it will correct it self because the ash cone is left to be flexible at the outlet end it is not a fixed opening at all. Put a bigger engine to draw on it the cone will open up automatically at the outlet end. Smaller engine it will close up at the outlet end. Self adjusting according to the vaccum pull. We see this in gasifers at the grate or with a grateless gasifer we call it purging after a period of time idling. I can see all of this happening in my mind. A flexible restriction zone with the reduction built in with it.
Yes do as little work a possible to make charcoal fuel. I like your style, Matt.
Bob
Yeah I think with mine there is a natural build up to the sides that forms and insulates and is self adjusting like you are saying. This is also the case towards the back side. I think Kristian isnt quite understanding my units as they are more of a down draft than they are a cross draft. The gas must pass thru the grate and this is at the bottom and there is a funnel that feeds to it. It is V shaped inside just bellow the jet and I have around 8 inches between the grate the jet. The oxidation does not go fully to the back of the unit and that area packs creating an insulation between this char ash accumulation and the pick up tube towards the back of the unit.
Without a doubt down draft can be done with charcoal, I have ran two units now with this set up daily since August nearly everyday. The units prior were updraft and did not have this revision. The gas exits much cooler than the updraft versions and seem to run more consistent. But I was also going thru a bit of a learning curve then.
So you are saying it is a diagonal flow that at the end is down draft at the grate. This is what I did in my gasifer now under the snow. Except it does have the fixed reduction hole with a grateless design at the end there is a large screen this part I am not sure if it will work. It might plug up, if it does it is easy to remove it, and go with out it.
Bob
The grate on mine spans the entire length and it has 1/2 slots spaced 1/2 inch apart. It is about 4 inches wide. The gasifier shell is 12 inches wide and is 12 inches to the back side where the pick up tube is. There are runners to each side that create the V Shape to the grate and this starts roughly 2 inches down from the jet nozzles at the front. These runners hold up the grate as well and the grate is removable for replacement. So far the grates have shown no issues at all. Ill take pics the next chance I get. Ill start building the next one here soon and will network them together once fully built.
So I pulled this unit inside to make revisions for the PCV hook up and to clean it out. This unit has roughly 10 hours on it and the grate looks the same as it did when installed other than it is black. Note the water tank and how I clean out the unit is by design.
