Safety considerations

I would like to add a few comments and ideas on safety concerns in the design of our builds. First a little bit about my past. I spent most of my life earning my keep trucking. And a good part of this time was spent transporting gasoline and fuel oils. This has given me an increased awarness of the hazards of flammable liquids and vapors.
As I am about to begin my first gasifier build I want design it with " safety first". The stock gas tank wil only be about 2 feet from the gasifier. I plan on removing it and replacing it with a rear mounted tank behind the axle. This will increase the distance between the tank and ignition source. And if a gas leak would develop, at least while the truck is in motion, there would be little chance of it coming in contact with a hot surface. Also I plan to have the air intake for the gasifier at least as high as the top of the bed of the truck and topped with a cap similar to the ones used on the older Farmall tractors. As flammable vapors are usually heavier than atmosphere a low air intake has a much greater chance of picking up a pocket of vapor. So that if you are sitting at a long red light and the vehicle next to you is dripping gasoline on the ground, things don’t go boom!
Hopefully others can suggest other areas that need considerations to safety. One area that comes to mind is the electrical part of our builds. And ways to protect the public from hot surfaces and sharp edges.

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Good Morning Mike,

Great topic, hope there will be lots of response because it is important it is kept near the front page.
I am pushed for time this morning and can’t respond with any depth but will be back before the day is out.

I would not put a gas tank down stream from a gasifier. Think about it. I would not put an air intake up where cold air and rain can get in it to cool the hearth. Done that. The bottom of my gasifier is cool to the touch. Anyone who is dripping gasoline will go kaboom from their own catalytic converter heat. Where I live in Florida the Forest Rangers told me during last years open burn ban they were not concerned about the gasifier at all. Just don’t dump hot char on the ground in a dry wooded area as it will ignite the dry grass. More fire are started by flicking cigs and dumping charcoal from grills. This is the main threat according to the Rangers. I think the real threat is a total lack of common sense.

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Hi MikeC.
Yes excellent topic you have started.
Best to break down this discussion into three general areas:

Gasifier safety considerations to the OPERATOR: Carbon monoxide poisoning, surface heat burns, poof-flash scares, handling of the toxic carcinogenic condensate, asphalt tars, ect. The char/ash is pretty benign unless inhaled by an asthmatic person.

Gasifier system safety considerations to surrounding people and animals: Carbon monoxide poisoning and hot surface heat burns. Most all of the others are within operator control and responsibility.

Gasifier system safety hazards to the surrounding environment. I am not an anal Green here. I mean woody’s reference to hot ash dumping ands stupid roadside dumping of condensates.

General considerizations:
Never, ever route produced woodgas lines inside the vehicle occupied spaces.
Never, ever operate or store a woodgas vehicle or ANY woodgasifier inside of a building or garage. NEVER! EVER!
Build /design so the all surfaces above ~140F/60C cannot be touched any time by anyone but the operator. Eg: cooling racks OK, most filter cans and condensate cans OK - most gasifer hearth cores Are NOT. In bed pickup truck builds the safest for this. Bystanders numbed dumb by a made safe for them world always want to lookie, toutchie, feel.
Operator must never wear Nylon or meltable synthetics. 75% cotton - 25% polyester is OK. 50/50 cotton-pylyester is about as far as you can push this. 25% cotton - 75% polyester NOT. This will melt to your skin! Hurts! Scars!
In Wayne’s 25% machine - 75% operator balance, the Operator should carry on board a metal ash dump bucket with a lid. Enough plastic jugs to hold trip drained condesensates and tars.

There is a start. Much more especially on a vehicle system you are taking out into the world.

Being seen as irresponsible Fellows screws us ALL in todays nanny state political environment worldwide and the USA sue a minute ambulance chasing Lawyer-land we are living with now.
Killing your self or someone else being the worst of all.

Regards
Steve Unruh

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I’ve wondered if solenoids linked to an impact kill switch would be in order. In case of collision all power to the solenoids would be cut isolating the gasifier air intake and gas out just like a fuel pump. Good idea? Might get gummed up I guess.

Woody… I plan to bring the air intake up behind the cab, ending at about the bottom of the window, with a proper rain cap. I expect it will be exposed to less rain than a low intake exposed to the tire spray when driving in the rain. The main reason I want to move the tank to the rear is to increase the distance to a known source of ignition. An additional benefit will be that I can then locate my condensate tank where the original gas tank was. I think that will make it much easier to plumb. And you are dead on about common sense and carelessness. When making a gas delivery at a station the first thing I would do was to get out the safety cones and establish a 25 foot safety zone around the drop area. And so many times a driver would get out of their car and drop a cig and step on it to put out. Safety greatly increased with the invention of vapor recovery. As the liquid gas fills the tank, the vapor is displaced and forced into your trailer. When you load your next load the vapor is displaced in your trailer and goes through a vapor line to a scrubber that returns it to a liquid. And what the ranger told you reminds me of an episode of COPS. An officer is involved in a chase that continues offroad. He becomes stuck in an area of tall dry grass. The hot converter ignites the grass and burns the car down.

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Hello, I am brand new around here so forgive my lack of knowledge. Can wood gas be produced at one local and stored in a tank like propane? I just keep thinking as I read about all this that that would simplify the conversion on a vehicle and solve some of the safety issues your discussing. I’m sure it’s been covered but I never have read anything that covered this.

My answer would be that it isn’t practical to store wood gas and it is dangerous because it is loaded with carbon monoxide. We use vacuum to keep the wood gas and toxins from escaping from the system and to route it to the engine as quickly as possible. Carbon monoxide will recombine with other oxygen atoms and form CO2 which renders the gas useless the longer it sits.

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Thank you, I figured there was a good reason. I just haven’t dug into this far enought to know better.

This thread brings a good question to my mind that I hadn’t yet considered. How exactly do you deal with the condensate? I was unaware that it was a hazardous substance and couldn’t just be drained anywhere. When I get mine built I want to be sure I’m doing the right thing with my by products.

Hi Steve,

Not toxic, semi-safe to pour out, but not pure water either. The oldtimers called it “wood vinegar”. Straight it kills grass or weeds. Diluted actually helps growth. Hopper condensate is a different critter, smells like BBQ and contains more tars, yellow fluid. Definite weed killer, be more careful with it. Also the settled tar is great for paving country driveways…

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Hmm. Not the point I was trying to make ChrisKY. Not cool anymore to be seen dumping anything public on roadside.
Live Rural take it home and use it.

I agree that post reactor condensate diluted will actually help some plants growth. It is slightly alkaline/basic good on my always acidic forest garden soil.
The yellow hopper condensate is an excellant insecticide spray as basicly the tree’s distilled out natural bug proofing elements. Is cell toxic.
Dip a bit onto the tip of your tongue. First very bitter, burning/tingling, then a numb spot. For me it takes a couple of days for the killed cells to regenerate back. Kills most bugs dead. Organic - biodegrades with time.

So both too valuable to throw-a-way anyhow.
The wood tars are a good wood preservative also. Kindling soak, dry and make into fire starter.

Regards
Steve Unruh

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I’m glad this topic has been brought up. It gives me the chance to ask about something that has crossed my mind more than once.
Since I have no previous experience with woodgas processors and I have not yet started my first one, I am completely in the dark on this point.
So here is my question:
Is it safe to pump gasoline into a vehicle that was driven to the gas station on wood?
Are there any other safety concerns when dealing with filling stations and woodgas vehicles?

Steve,

Of course I meant dumping at home - and the largest volume comes post-reactor in a Keith gasifier at least. But you should know what you’re dealing with, even at home. Wayne dumps the yellow hopper stuff on weeds to keep them down, and drains the tar on his driveway. You can probably find a safe place to put the wood vinegar once diluted, like I say it’s actually beneficial.

Another issue is smell. My hopper condensate tank is leaking a little and every drop carries a strong BBQ aroma. OK in the country, but maybe not so in town. The leaks will plug up soon with tar. Till then I am careful not to park on good grass.

Lou
It is always recommended that when handling any flammable liquid that a distance of 20 - 25 feet be maintained from an ignition source. And make sure your build includes an operator controlled valve on the combustion air intake. I plan on using an old throttle body with a pull cable.

Hopper juice can be recycled back into the hopper once the gasifier is heated up and if you continue to drive. Has to be put in on top of a full load of wood and it has to be a good gasifier like Wayne’s to handle the moisture. Done it many times in the Ranger.