what comes out is burning gas, i will say…try to fix the blower with a pipe to the nozzle, in way that the blower not melts…so that the blower pushes air inside…
what diameter has your gasifier? maybee the coal non flows down…(because of rusty inner surface of the pipe)
try to ignite the coal through the nozzle , when it glows, screw fhe pipe with the blower on the nozzle hole - must not be completely airthigt- and than gas should come, not overpull the system with air, otherwise you get a hollow burn easily…
when the heat inside is not enough, gas cannot be produced, try a provisoric insulation around nozzle area and reduction area…easily made by a piece of rockwool.
what temperature you have actually outdoors?
5 Likes
Well, if you have no air leaks and your gas isn’t being polluted by the blower then fuel size is just about all that remains. It helps if you have a video showing what’s happening. When I started with a simple fire I was having the same issue you are and I did a video of showing my fuel and filling the hopper and MattR pointed out that my fuel was much too dirty because I didn’t take the time to sift all the char dust out. Once I did that, problem solved. Don’t pay any attention to Dr Ruth. Size does matter. Also I thought I had everything sealed up but on the bilge blower I was using, the wires for the motor come out of the plastic casing and there is just the slightest opening. That was enough to stop flare as well. The smallest amount of air bleeding in will screw up the gas.
10 Likes
Thank you all for information
@giorgio my outdoor temp is 35 celcius
Today I decide to mix wood and chacoal together and test again.
fisrt layer is chacoal to make it easy to ignite after that is wood chip.
/////Start up process.//////
I ignite chacoal and blow air into bottom port.
first 15 min it come out a lot of smoke.After smoke is a lot less. And finally it can flare but not stable and very little fire. As I attached second pic.
I think my main problem is chacoal and wood chip size and quality.
What do you think ?
.
3 Likes
read a bit around in my thread about cooking gasifier, more down is described a small diameter gasifier and his difficulties, till it works fine…
in the begin try only with charcoal,because your gasifier design is not good for wood-woodchips. charcoal : right size and all dust sieved out…
blower speed not to strong, otherwise hollow burn…no gas
try a insulation around the gasifier from the bottom up to 50 cm high…described in my thread…i think your inner temperature is too low…
my gasifier in this design needs 7 minutes to deliver burnable gas, after 10 minutes gas is constant good…at least i constructed my gasifier with 4 nozzles for not having problems with fuel flow…will say the fuel-coal- not flows down and creates a hollow space and than, of course, gas cannot be produced more…iron pipes inside ofen are rusty and the fuel cannot flow down…
what diameter your gasifier has?
what will you do with the gasifier?
is your charcoal umid or dry?
5 Likes
Don’t mix wood chips into an updraft, it doesn’t crack the tar like a downdraft does.
7 Likes
Here you can see the size of my charcoal. I quenched it with water so it was damp. But now I do not quench with water, just stop the air flow. My pipe is 4.75 inches inside diameter. It should be at least 6 inches inside diameter. @k_vanlooken told me this. But it works. My pipe gets very hot on the outside, 850°F.
Here is all of the information about my project. Charcoal Gasifier for Generator - #486 by r_wesseling
8 Likes
hello rindert, your small diameter gasifier has one nozzle, right?
with one nozzle i have had though fuel hang ups and therefore interruption of flow of good gas…
i think, when - for example -a one cylinder engine runs with the gasifier,(connected only with a rubber hose) because of pulsating negative pressure created from the motor, the fuel falls easier down , also when the motor is not connected by frames or so to the gasifier (vibrations of the motor help against fuel hang up)…
a still-standing gasifier how mine for cooking for example is from my sight more exposed to fuel hang ups, so at least the solution with 4 nozzles (like stephen abadessa´s) works reliable.
5 Likes
Hi Giorgio,
Yes, it has one nozzle. I used @k_vanlooken recommended size hole. Koen also recommended the charcoal path must be at least 600mm. I think this 600mm is very good information because the engine would stop when the fuel was used and fell below this dimension. I used info from Koen’s thread Some school in Thailand.
Rindert
2 Likes
@giorgio my gasifier is 6 ". For demo my goal is create electricity.
my chacoal is almost dry. Today I have done test again I need to blow air inside long enought to make temp inside high enought then it can generate gas to ignite. So you observation that my gasifier is not hot enought is reasonable. but it is still not constant.
2 Likes
CK , sometimes for no reason it can be a pain to get a flare due to air leaks or too large a fuel or maybe even charcoal being too wet .
Don’t put anymore wood chips into your gasifier just small sized dry charcoal for now , where the gas comes out i want you to put a tin can with a hole in the middle for the gas pipe and all around the bottom edge of the can drill or punch as many air holes as you can , this should help mix air in with the gas coming out of the gas pipe .
If you start by sucking and get the charcoal alight then place the can on the output pipe and blow into the nozzle with your fan with a steel pipe so as not to melt the fan , that WILL get the charcoal glowing hot .
Dave
8 Likes
maybee when the gas goes off, easily can be the reason that the fuel not flows down, so you get hollow burn…in this case, for searching the reason, take a wood-branch and give some strike to the gasifier to make the fuel coming down…when you get than a flare again , so probably fuel hang ups can be the reason…
or too less insulation…
you have no vibrations or suction pulses on the system, because there is no motor yet…so this kind of gasifier can easy create problems…mine was the most difficult from the 5 gasifiers i have built…
when you will produce electricity it will be more reasonable to use a bigger diameter, for example a propane tank…keeps more heat inside, and combined with the vibrations of a engine the fuel flow is normally no problem…
6 Likes
Comparing a gas mixer and a gasifier, I could summarize certain similarities, vacuum and physics will do the rest
5 Likes
If the gasifier is 6" in diameter, a 1/2" opening would be suitable for air intake, and you can pull the top with a powerful fan, and good gas should come out.
10 Likes
I have one simple fire with a 6 inch diameter which is inside a 5 gallon pail and the space between them filled with refractory cement. It uses a side fed pipe like Tone shows with a Bryan White type pipe cap nozzle on an elbow. It Disperses the air like Tone shows and this seems to prevent any bridging caused by a smaller hot zone. Very Simple. Makes good gas.
9 Likes
Thank you everyone.
I have plan to build new gasifier for solve insulation and diameter and nozzle problems.
Is it possible to use old LPG gas tank ?
or old refrigerant tank?
3 Likes
this is my first gasifier … with propane tank… look a bit more down, there are explained modifications…i mad it higher so a 200ccm engine runs for 6 hours…
electricity generator in the same size needs more coal because the rpm is higher -determined from factory…
English-Manual-V3-PDF.pdf (2.1 MB)
look also here, from eddy ramos, simple and effective gasifier…not only for driving, also for stationary use…
7 Likes
Be safe. Fill the tank with water before you cut it. This so you will not make a fire or explosion.
Rindert
5 Likes
Please be safe, here is how to safely dismantle a propane tank. After removing the valve, fill it entirely with water. I fill it up and empty it twice before cutting.
Also be careful with refrigerant tanks, most refrigerant is flammable. A Helium tank would be safer because helium is inert.
7 Likes
Hi CK can i make a suggestion , i am unsure of the size of generator/ engine you would like to try out on your first build ,but can i just maybe try and save you some time , please ignore me if you think i am being too over powering with my view , but don’t start making a new gasifier out of those propane bottles or the old refrigerant tank unless your engine is real small and you don’t intend to run it for more than maybe 40 mins at a time as a updraft gasifier as it will run very hot after 30 mins , the 6 inch tube gasifier you already have will work for you , fix that first before moving on to something else .
As others have mentioned , start off with small charcoal from 3 mm up too say 20mm max also make sure you sieve out all the dust , that is very important , once you have that flaring off and you have a filter attached try running your engine it really is that easy , as long as there are no air leaks and fuel is to size you should be making gas no matter how little or large your air flow fan is .
Dave
11 Likes
Thank you guys for remind me the risk of propane tank I will do with very careful.
@d100f actually these is demo gasifier for meassurement before move up to bigger size gasifiier to run with engine. before I build big I want to make it work with my hand first.
I want to measure tar content ,cold gas effiency, etc thats why I am building small one first.
I will keep in mind about charsize. charsize is the thing that I am not focus enought.
4 Likes