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Old 02-14-2014, 10:04 PM
Freeman` Freeman` is offline
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Question Arrested Burner

I have built a wood gasifier. I have a 3/4 inch pipe coming out of the top for the gas outlet. It's a smoky gas. There is no pressure build up, just an inlet fan pressure determining the gas-out pressure. I want to put a burner on top of the outlet pipe that can be lit and I don't have the funds to buy anything. I am confident in my fabrication skills and my ability to grasp a new concept. I've seen others make a burner with a tin can with holes in the bottom of the sides; Theirs was safe during operation. My concern is flashback. I couldn't find a detailed description of its fabrication. This may not be the place for this post, but I am not sure where I should put it. Can someone help me understand the fundamentals of flashback prevention and how to construct a burner? I want to understand the concept, not just to try it to find out. I would be very appreciative. Thank You.
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Old 02-14-2014, 11:08 PM
Dr_Stan Dr_Stan is offline
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I did a search for "wood gassifier" and had 451K hits. Its an old technology so there is quite a bit of info available. I even saw a car converted to run on wood gas during WWII in the German Museum of Science & Technology in Munich.
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Old 02-15-2014, 12:29 AM
Freeman` Freeman` is offline
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Yes, but what about instructions for a tin can burner straight off the top of a 3/4 inch pipe? pretty much, if i slap a tin can on the pipe and drill holes all around the bottom sides, will the flame flash back into the tank if the gas is coming out of the tank at, we'll say "strong" velocity?
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Old 02-15-2014, 04:19 AM
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I admittedly have not built a gassifier but its on my to do list. As such I have done a tremendous amount of research including the 5 of so research papers out there. I have yet to see one with a flash arrestor. Most of the time guys are cracking valves 3" from the unit and checking with an open flame to see if they have gas. My personal and very unscientific belief it that its not truly a sealed container and not a explosion hazard. The amount of volatile gas inside the producer is small and there is a vent on both ends. In the unlikely event it did flash back it would probably just fart out the two ends.
I have quite a few factory made propane burners with no safety device and have not had issues.
If you truly believe you need one I am very sure you could adapt one from a O/A.
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Old 02-15-2014, 07:46 AM
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Ironman Ironman is offline
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Quote:
Originally Posted by Freeman` View Post
Yes, but what about instructions for a tin can burner straight off the top of a 3/4 inch pipe? pretty much, if i slap a tin can on the pipe and drill holes all around the bottom sides, will the flame flash back into the tank if the gas is coming out of the tank at, we'll say "strong" velocity?
Pressure determines the velocity of the gas out of a burner, and the burner velocity must just exceed the burn speed of the gas, and if the pressure drops, and the flame advances back into the burner, it must at that point, be unable to get oxygen. My concern is the fan you say is pushing air? into the burner. In the automotive burners I have seen, they operate on engine vaccum and the vacuum draws the gas from the gassifier.

I see that a gassifier if fan fed will work for you to a point where, as the fuel expires, and the fan keeps pushing, you will get CO and oxygen at the burner head, and sooner or later fall into the explosive range.
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Old 02-15-2014, 12:32 PM
Freeman` Freeman` is offline
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Thank you guys. I am certain now of a few additional systems before testing, thanks to your input: #1. The filtration system #2. Vacuum fan.
Filtering the gas in-line will prevent the fan from gumming up which it would certainly do if pulling the gas. I need the separate, removable vacuum to prime my tank initially. Engine vacuum will replace the fan suction.
Getting ahead of myself has proven to be a great teacher to my approach. Still have the characteristics of this shortcoming, unfortunately I was hoping to test the flammability of the reduced gas because i was aiming for the good feeling of a founded checkpoint. But I am not ready for this just yet, as i see. Again, Thank you guys for your input.

Last edited by Freeman`; 02-15-2014 at 12:40 PM.
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Old 02-15-2014, 03:56 PM
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Shopmonkey Shopmonkey is offline
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Thinking out loud here: What if the fan was put in line, after the source of the gas? Blow toward the burner using a venturi, of some sort, to draw the gas into the airstream. This would keep you from running gas through the fan, and might keep you from overpowering the flow and creating a problem. It would, also, keep the pressure up, at the burner, helping prevent backflash.
Maybe I don't know shit, here, it's just a thought.
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Old 02-16-2014, 08:55 AM
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Some where in my shop files at home, I have a step by step on building a gassifier for a car.
Here is a site that discusses filtration and other issues, which you may have seen.
Two cautions on your project....
1) this is a very toxic gas and any leak can be fatal, especially if driving.

2) the same moonbats and green assholes who promoted global ice age in the 1970's and told you how to heat with wood and build woodstoves, are now making a concerted effort to ban all wood burning. They have already succeeded in areas of Canada. So beware that besides being classed as a terrorist for making a toxic gas, you may be fined for lighting it up.

This information and skills to gassify solid combustible as a way to survive are worth experimenting with, and when and if the system collapses of it's own corrupt weight, then this sort of device will be worth it's weight in gold to drive a flour mill, etc.
I also have purchased years back, a set of plans held under patent form General Motors. It seems that at the same time as they were doing their patriotic duty in WW2 manufacturing tank engines, they were also manufacturing wood gassifier units they sold to the Third Reich to run vehicles in Germany.
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Old 02-16-2014, 09:44 AM
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Screw running just a flour mill, I'm going to run the house, shop and air conditioners! I found these about two years ago an I'm fascinated by them.

http://www.gekgasifier.com/products/product-overview

Note that the Kubota units are sold out through 2014......



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