Here is a short video on safety when handling methanol. it also shows a safe method of transferring methanol from drum to carboy.
That video might ignite (no pun intended) the whole discussion on the safe pressure limit for a 50gal barrel. Those little tire pumps are capable of 150psi, at least the ones I have seen. A steel drum is only safe to 3-8psi, if I remember right. A plastic drum can hold a bit more pressure...maybe 10psi.
When I have pressurized a drum I have used a rubber stopper to hold the air line in: built in safety valve. The stopper will pop out of the 3/4" bung well before the pressure where the drum will explode.
Good point about the possible pressure produced by the tyre inflator. It only takes about 1-2 psi to pump the methanol out the pipe. The pressure will not increase as long as the lever valve is open. I suppose that if someone turned on the pump with the valve closed and left it to pressurize for long enough it could burst the drum although its more likely to burn out the inflator first.
I hope its obvious from the video that its only for attended use while filling containers.
To anybody with some experience. But I think a lot of brand new guys look over this forum (THE biodiesel forum, in my opinion). Best to at least mention some safety limitations, even if (and hopefully) they don't lead to pages of arguing about them!
Good video, but like the previous one the sound level is too low. It's barely audible even with all playback sound control at 100%. The description of the air pressure fitting was inaudible and the camera not close enough to see what it was.
In your video you say that methanol is more inflammable (flammable) than gasoline.
The definition of a flammable liquid in the USA is one that has a flash point less than 100 F.
The Flash point of methanol is 52 F, has an auto ignition temp of 867 F and is a class 1B flammable liquid.
The flash point of gasoline is -40 F, has an auto ignition temp of 475 F and is a class 1B flammable liquid.
Edit: Gasoline is a class 1B flammable liquid not 1AThis message has been edited. Last edited by: jacobh,
Its certainly more DANGEROUSLY flammable (inflammable), in my opinion, since it burns nearly invisibly.
Methanol is just as dangerously flammable as gasoline. The relative flammability is immaterial from a safe handling standpoint. The important point is that it's as hazardous to handle as gasoline
On the other hand, after the 1964 tragedy at the Indy car races they changed fuel from gasoline to methanol because it is a safer fuel having a higher flash point and a methanol fire is easily extinguished with water.
"A seven-car crash on the second lap of the 1964 Indianapolis 500 resulted in USAC's decision to encourage, and later mandate, the use of methanol. Eddie Sachs and Dave MacDonald died in the crash when their gasoline-fueled cars exploded. The gasoline-triggered fire created a dangerous cloud of thick black smoke, which completely blocked the view of the track for oncoming cars.
Johnny Rutherford, one of the other drivers involved, drove a methanol-fueled car which also leaked following the crash. While this car burned from the impact of the first fireball, it formed a much lesser inferno than the gasoline cars, and one that burned invisibly. That testimony, and pressure from Indianapolis Star writer George Moore, led to the switch to alcohol fuel in 1965."
...and that has what to do with biodiesel safety? Gasoline isn't an option for making biodiesel is it? This is a biodiesel forum, not a car racing forum.
I don't know. You were the one who said "Methanol is just as dangerously flammable as gasoline" not me. I was just trying to help you understand what you were talking about.
I am sure we have all siphoned a gas tank and got some fuel in our mouth. It would be fatal if it was it were methanol. If it was ethanol you may feel the effects of moonshine.. e85 smells really potent and i know this for a fact!.
Jacobh, you are right Methanol is not quite as flammable as gasoline, in the video I was trying to give biodiesel brewers, especially beginners, some sense of how dangerous methanol is and how important it is to handle it carefully. Gasoline is a reference that most people will understand and while I may have overstated the case, I would rather users were too careful than not careful enough.
RyanP your point about the potential over pressurizing of the drum is a valid one. Would you do me a favour? Would you post a comment about it on the utube channel and then I will post a reply agreeing and reinforcing the point.
Yeah, no problem!
40ml of straight methanol will kill a 200Lb man; lesser volumes will still potentially cause any number of serious health problems; including but not limited to liver damage and blindness.
Methanol's effects are cumulative, but are super ceded by the ingestion of ethanol as the body processes ethanol more readily than it does methanol and it, for all practical purposes, acts as an antidote.
Personally, I keep a bottle of Absolut Vodka handy for when I will be working where potential methanol fumes may be present.
** Biodiesel Glycerine Soap - The Guide
- on 5 continents helping people make & sell soap from the Biodiesel Glycerine.
imakebiodiesel, please do not take the following as a personal attack on you in any way. You are an asset to the biodiesel making community. It is not my intent to disparage you personally in any way.
I just watched the video and IT SCARED THE HELL OUT OF ME!!!
PRESSURIZING A STEEL DRUM TO PUMP OUT THE METHANOL (OR ANY FLUID) IS EXTREMELY DANGEROUS!
THIS VIDEO SHOULD BE TAKEN DOWN IMMEDIATELY! BIODIESEL BREWERS (EXPERIENCED AND NOVICE) SHOULD NOT BE ENCOURAGED TO USE PRESSURIZED AIR TO PUMP OUT A BARREL!
Steel drums are designed with enough strength to contain the contents during transport, handling, and storage. The drums ARE NOT DESIGNED to withstand internal pressures created by piping compressed air into the closed drum.
Human nature being what it is here are some things that can go wrong:
1) The air compressor is turned on and due to a distraction, neglect, or ignorance the valve on the methanol lance is never opened. The pressure will build inside the drum and the drum WILL explode!;
2) The air compressor is turned on, the methanol is successfully removed, but due to a distraction, neglect, or ignorance the valve on the methanol lance is closed but a delay occurs before the air compressor is turned off. The pressure will build inside the drum and the drum WILL explode!;
3) The air compressor is over-sized and the methanol lance valve is too small. The compressor supplies much more air volume than can be safely relieved by a wide open valve on the lance. The pressure will build inside the drum and the drum MAY explode!;
4) In an attempt to speed up the transfer process, the operator purposely increases the air pressure to make the methanol pump faster. This can lead to a growing pressure differential inside the drum. The pressure will build inside the drum and the drum MAY explode!;
5) The system works correctly, ie the compressor is switched on, pressure builds, methanol is pumped, the methanol valve is closed, and the compressor is switched off. Everything looks OK, but the drum is left in a pressurized condition! Any small leaks in the drum, fittings, or equipment will result in a slow leak of methanol vapors or liquid into the storage area. This condition is obviously unsafe as has been discussed on this forum on numerous occasion.
If a person was to ignore these warnings and go ahead and use this method, then a couple of operating recommendations and slight design changes would be prudent.
A) Instruct the operator to start by opening the valve on the methanol lance first, then switch on the air compressor.
B) When the transfer is complete, switch the air compressor off first, then close the methanol valve.
C) Add a manual pressure relief valve in to the air line and open it completely to relieve any residual air pressure as the last step in the process.
A few years ago a friend of mine installed a steel tank in his shop to hold used motor oil for transfer to his used oil shop heater. The tank was a common 270 gallon, oval shaped steel tank designed and built to ASTM standards for holding home heating oil inside a residence. The mechanics hooked up an air line to the tank and equipped the draw off pipe with a valve. Functionally this was an identical design to what is shown in the video. During one particularly cold morning the mechanic was pumping the cold oil to the shop heater by opening the air pressurization valve. Even though the draw off valve was open the extra air pressure, caused by the increased viscosity of the cold oil, over pressurized the tank. The tank exploded, killing the mechanic. The set up as shown in the video can lead to the exact same result, and since methanol is being pumped a fire could also ensue.
I'll add something, too. Once you're done pumping, what would be the safest method to then vent the pressure back out? That air is methanol-laden. I just point it away from my face and make sure the doors are open, vents are running, fans are running, etc. Then go have a beer, just to be safe.
I agree with producer that pressurizing a drum is dangerous business. However, no matter how many times it is discouraged, the idea seems to come back like a bad dream. I'm ready to look at how to make it safe rather than discouraging it's use. This will not be the first time we've pitched in to overcome the safety faults of specific equipment.
Ryan's idea of using a rubber stopper on the input is good. There may be other approaches that will also work to prevent overpressuring and limit exposure to methanol vapors. I like the idea of using a portable tire inflater rather than using shop air because it takes a really long time to build up pressure to dangerous levels.
We do have an example to look at. Pressure operated centrifuges need a relief valve installed in them to prevent over pressurizing the centrifuge. If the relief valve were able to be manually operated to bleed the pressure and dumped in a bucket of water, vapors would not be an issue.
Producer, I never take offense at criticism, especially well thought out and reasoned criticism. I take your point, accidents can and will happen.
The amount of pressure needed to empty an drum is very small, 1.7psi in fact, but there is a danger that the drum be subjected to a lot more pressure than that by leaving a tyre inflator on too long or using a large compressor set too high. What is needed is a fail safe, some form of pressure relief valve. The lowest type of prv available commomly here is 3bar,which is 40psi, so thats no good.
Ryans idea of the bung would work. I have replaced the fitting with the tyre valve with a tee fitting. One outlet of the tee has the tyre valve and the other outlet has a plastic wine cork pressed into it. It is a good fit and with a little ptfe tape it will hold until I exert just over 2psi. I intend to test it a dozen or so more times but it seems to be very consistent.
I do my methanol transfer in a covered but outdoor space so the escape of the methanol laden air from the drum is not a problem, if this system was to be used in a confined space the improvised pressure release valve could be extended to the outside of the building with a length of pvc hose.
I will take some pictures and post them soon. I would welcome your comments.This message has been edited. Last edited by: imakebiodiesel,
|Powered by Social Strata||Page 1 2|