Glad you were able to diagnose the leaky filter - air leaks can be a real pain. You are running a pretty small engine, right? What is the displacement? Your grate is acting as your nozzle in this design, so the cross sectional area of all those holes (plus any space that air can seep around the edges of the plate) will determine the airspeed into the reaction zone. Higher airspeeds make better gas, or at least so says the literature. In practice, it seems there is a wide acceptable range. Once you have it up and running, you could try playing with the size/number of holes. I am curious how much ash you will be able to shake through your grate, since the engine suction is going to be trying to pull it along with the gas.
I was amazed at how much ash rained down from these big fires we had. Even 10 miles away there was enough to cover every surface inside the shop where the garage doors were left open. Down at my place I was less than 2 miles from a little 10 acre spot fire, and I found little piles of charred leaves and pine needles that had been burned down to ash and lofted all that way.
389 CC engine on that model Generac. It sucks a lot of gas when it’s running but it took a couple minutes for the gas in the fuel line and bowl to run out when I closed the petcock today. Seems odd. I did get the engine to run on wood gas but just barely. Gary is right that I’ll have to go right into the throat of the carb. The propane carb is just a series of holes around a aluminum doughnut. I’m sure it need the pressure of the propane to function. At least I know it all works now. I can mess around to get it all working well as we go. Running on gas it seemed that the generator was rattling the gasifier enough that a grate shaker should not be necessary. If it’s too much like Steve U suggested I’ll try and and isolate the generator from the gasifier some way. Maybe some rubber motor mounts or something. I’ll cut in the inspection port and empty the remaining charcoal that’s in it, probably tomorrow. then we will see what it looks like at the grate.
About 20 years ago a big tire dump site caught fire about 30 miles from where we lived. I think they estimate over a million tires there. Took forever to get them out and it was winter so even the snow at our house was covered with black soot. Can’t dump tires in this state any more. I’d like to have a lot more of them myself. Stacked up they make excellent compost bins.
I cut up a truck load of branches and fed them into the barrel all day. It was full to the top with mostly coals when I put the lid on. Should have about 30 gallons of new char tomorrow.
Been raining on and off for the past two days. Haven’t been able to uncap the charcoal barrel and process that. I did get a chance to make an adapter plate for the carb and get that all mounted and plumbed back to the gasifier. I made a 4x4 inch inspection/cleanout port out of 2x2 angle and cut a hole out of the hopper just about the top wheel. Emptied the char out with a shop vac. With the angle fitted in I could not reach down to the grate so that was a fail. I’ll have to patch that hole and move the port down into the wheel, which I didn’t want to do. Hasta manana. I did get my two thermocouples delivered a couple days ago. I could use some advise on where to best locate them.
Hi Tom , i have never used a thermocouple on my charcoal gasifiers , but i think the best place would be towards the top of the hopper to let you know when your charcoal is running low .
and one down by your hearth where you inject your water maybe
Made some additions to the gasifier today. The only dry day for this week. I should have did this earlier but got in a hurry to get it working. Cut an access hole in the hopper but it was too high to reach in and get at the grate but I already had the frame and lid made so I stuck it in anyway. Then I cut a round opening for a four inch pipe ring and put it in one of the wheels right at hearth height.
This took a 4 1/2 in hole. I don’t have a hole saw that big. I know this isn’t news to some of you long time fabricators but in case your experience level is less, here is how I do these. I trace around the piece I want to put in and then drill a million holes around the perimeter just inside the line. I make some close enough to open up a slot big enough to get a metal recip blade in and cut from hole to hole with that. Then with a angle grinder and grinding wheel I smooth out the edges until the piece fits perfectly. Seems like a lot of work but it took me ten minutes to cut this hole.
Ordered this today to read my thermocouples. I ordered some high temp ones a while back and this one comes with four that are not high temp. Still the reader needs to have all four pin ports filled so I guess I plug them in somewhere. I don’t know what they are supposed to tell me, but monkey see, monkey do.
Well Tom if i were you i would put 1 in your tea cup ( hate tea getting too cold )
another one, out side the work shop ( to let you know its time to light the fire )
I guess you could always put the 3rd one in the top of your fuel hopper just to give you a heads up its getting warm and time to take off that woolie jumper you have on so that it doesn’t get covered in charcoal dust when refilling .
As for the 4th one i have no idea at all , maybe keep it as a spare or to tell you that your chicken soup is getting cold as well maybe
Dave
All righty then. I knew I could count on getting some good advise here. I remember you said you don’t use them Dave. How do you know how your supposed to dress?
Hi Tom , please don’t think of what i am saying as good advice , i have a very active mind and imagination and if told something cant be done trust me i will do my best to prove them wrong , a few times i have smiled all the way to the bank and stuck a finger up to those so called smart arse’s ,learning in life that not everyone wants you to succeed in life as they have plans for you for when you have tried and failed .
If something is not broken i do not fix it , sure i think about how it can be improved and i say to myself the next time it breaks down i am going to do it this way or change that , remembering only ever change one thing at a time .
So how do i know how to dress ? simple i copied the master he showed me ,and sure he has also shown me other ways to dress but i stuck with the first way he showed me till that way fails , after all why complicate a simple way ( Thank you Gary Gilmore ) .
If you are building a charcoal unit then you know when its hot enough as it will start to produce gas , you will also know when its starting to run out because it will be too damn hot to touch ! There you go that touch of the hand on the charcoal gasifer just saved me $$$ having to buy a thermocouple or if i am away inside the house and the engine stops after 4 or 5 hours i know the drum is empty another $$$ saving not having to have it Bluetooth to my smart phone i just listen for the piece and quiet again and all is well with the world ( well my world at least ).
There are many charcoal Gasifier designs around the world i just happen to have Gary’s simple fire one that runs and runs and runs , now i have sorted out the nozzle once and for all , it does exactly what i want it to do and that’s run a 8kva generator unattended for up to 5 hours at a time .
Dave .
Well riddle me this batman. Can I open the hopper to add more fuel while it’s running and if you let it burn out and can tell by the temp on the outside, is your gas hot enough at that point to damage the plastic flexible hoses feeding the filter? Inquiring minds want to know. It’s ok about the money for the thermocouples. Trump sent me some money a while back and I’m still using it.
Hmmmm well nope , not a good idea to open the hopper lid whilst running , unless of course its a downdraft guess u can get away with doing a fill on the run , i have in the past on smaller gasifiers stopped the engine and opened up the lid and dumped a fresh load into the hopper and started the engine up straight away again
I only used a plastic hose once when i first set up a 20 litre tin as a simple fire running a lawn mower engine as it was the first few runs i was eager to keep checking how much longer i could keep engine going before running low on fuel and noticed that after about 30 mins the hose was sagging and flexing a lot with the pulsing of the engine , that sorta gave the game away as it was time to stop and refill .
I am not saying i have never used a temp device before , i think with each sized gasifier i have built i sometimes have used a non contact gun to give me an idea of temps of the outside top and bottom of the drum and to calculate the run times of each sized Gassifier , its something i think you get a hang of pretty quick to how your build is running .
It must be lovely to have friends in high places sending you money to play with your hobbies .
Dave
They said they were going to give me more. Economy is shot anyway. I’d rather get it and use it to build something. They just use it to destroy things.
Winter is coming. I’m spending most of my time right now cutting, loading, hauling, cutting, splitting and stacking firewood. Everything too gnarly to stack well goes in the charcoal barrel. I think that when I last reported on this project I had it disassembled and adding cleanout/ grate access ports and getting the carb hooked up. Well finally took some time and put it all back together. Ran the gasifier on the flare for a half hour while I tried to fix the broken starter rope on the generator. That wouldn’t rewind all the way when I was done but enough to get the engine started. Ran it on gasoline to get it warmed up. Switched to wood gas and it ran great for about an hour. Then it started to lose power and there was some smoke coming out of the water line holes and the grate shaker hole. I had not put any water in the tank yet and I shut it down. Filled the tank with water and filled the reservoir beneath the grate. Plenty of steam pouring out the plenum beneath the grate. Not sure what changed from it running so well to going down hill. It had about 25 gallons of charcoal in the hopper than was taken right out of the barrel sized and dumped in the hopper. Couldn’t be dryer but the glass under the cyclone still had a few ounces of water in it after running just that long. I’ll run it again tomorrow with the water feed working. I need to get a sight glass into the water line to see how how much it’s dripping but it can’t overfill the reservoir because of the overflow tube. Any suggestions from you experts?
The thermocouple reader finally arrived today. I haven’t drilled to install the thermocouples yet. I thought the high temp ones were sized for 1/2 inch NPT but the ones I got were something like 8x1.2 or some odd metric size. All metrics is odd to me. For some reason I actually had taps and dies that size so I’ll probably stick those in tomorrow as well. Anyway I was super happy when it was running so well.
Hi Tom and congrats on getting your unit up and running even an hour run time is an achievement worthy of a few lemons , hope you made a video
I think Don or Gary are the smart ones to help out with your sudden smoke and lack of power as they knows this style of system better than anyone .
well done
Dave
Thanks Dave. I don’t sleep that well anyway so I woke up at 3am thinking about this. Now I’m concerned that when I dumped the water into the hot hearth that the big burst of steam may have wet down m y char above the grate and I will have trouble making burnable gas. I guess we will see in about six or seven hours. I’ve been wondering, since so many here post video, do you have to have a you-tube channel to do so. I know nothing about such things.
Hi Tom yeah i think you will need a YouTube account ,i am no expert when it comes to that i just upload the odd video when asked too .
A little dampness will not affect your running that much to be honest , if you hear it crackling and popping when first lite and plenty of smoke blowing out the fan wait a little while longer and then light your flare , it should come good after 5 mins .
Dave
I’m going to look into the video thing. I’m lucky I have enough of a brain to get on-line at all. Not what you would call a computer geek. I ran the gasifier from 9am til 2pm today. Took a good ten minutes to get it to flare but ran fine with no issue for five hours just flaring the gas. Pull rope on the gen wouldn’t work so I couldn’t run the generator. Took me a while to figure out how to re-tension the spring and by then I had to go do something else and didn’t want to run it without being somewhere nearby. Tomorrow is another day. As I said, no issues at all. Fed it water all during the run but the flare is just about invisible so I couldn’t tell if there was any difference in the color of the flame.
Here is a picture of the shaft the recoil starter goes on. I haven’t seen any of these before so I couldn’t figure out how to rig it so it could be started with a drill. Maybe yours has an bolt or something at the end of the shaft,
I know all you long time builders have your own ways to do charcoal but I think there are some new people building here even after I started. I think that some of these things may seem more complicated than they should. I posted a picture of the little grinder I use to get the stuff out of the barrel down to half inch or less. I sift it down to a quarter inch with a very simple tool. It’s just a five gallon bucket, cut in half. The bottom is cut out and a piece of expanded metal lath is bent up over the edge of the bucket. The the top half is slid up over that to lock the lath in place. You could probably use hardware cloth, but I don’t think it would form around the bucket as easily. I’m also going to post a picture of my tumbler. I use that to separate worm castings, but it would also do char. I just never needed that much up to now. It was also a pretty easy thing to build. Be glad to explain how if anyone wanted to know more. Anyway I can grind and sift a five gallon pail of raw charcoal with my grinder and bucket in less than ten minutes.
Hi Tom , if you have a cordless hand drill or even a mains one i just fire up smaller engines with a socket on a short extension bar into the chuck of the drill .
I don’t do complicated anymore now i have retired i always go the simple easiest way to get things done, the bucket sieve is a great idea , when my plastic shop bought one breaks i shall build myself one of those too .
On starting up on old charcoal i find it helps if you can poke something into the gasifier to break up some of the old charcoal to make it a bit more reactive again just around the nozzle that should speed up your start up time a fair bit
Dave
Hi Tom, Glad you have your charcoal gasifier up and running. (Now just get the generator fixed!)
Now you will be learning the quirks about running a charcoal gasifier. Basically they are very easy but there will be issues that pop up to test you. For example I was giving a demonstration of running my Gravely on chargas then switched the gas hose over to run a portable generator. It would run a little and then shut off. I did everything I could think of to troubleshoot the problem without tearing the whole system apart. VERY frustrating because there was a problem and could not easily find it. When I got back home, the cyclone was taken off and there was the problem. Pieces of charcoal had lodged in the intake and nearly plugged it. Chock up another charcoal gasifier learning experiance!
A few suggestions; You can use charcoal from 1/8 to 3/4 inch. Basically screen out the dust and any larger chunks. This should reduce the amount of work needed in fuel preparation.
Be careful when adding water. The tendency is a little is good so more is better. Not true. The fact that you have water collecting in the jar under the cyclone indicates to me the charcoal is damp or too much water is being added and not reducing to H2. When I do add fluids, such as water, I like to run the gasifier for several minutes after shutting it off to drive of any moisture remaining in the char. If you have moisture in the char, it is harder to light and takes longer to make flare-able gas. Dry charcoal lights in several seconds and gets good gas quickly. I believe Koen actually dumps the old charcoal and starts each session with a new batch. I’m too lazy to do so and try to keep my char as dry as possible by shutting off the fluid several minutes before shutting down. Also consider the humidity. On damp days I do not use water because there is enough water in the intake air to create the H2. Adding more water at that time will just dampen your charcoal.
You are definitely on your way. As I’ve said before, charcoal gasification is easy and dependable. It works. If there are problems, they can be found and fixed.
Get those lemons ready
Gary in PA
Let me just point out what Gary allredy sayd. Only shake off the dust. I have found charcoal gasifiers work best with 1/2" charcoal with all the fines left in, just sift the finest dust out. Its allso more economical.
