I've used GL's 1 day process for about 6 batches now and just recently came to posses a gas detector. This nifty device lets me know how much explosive gas is in the air. I've been using an older method of GL's to drive off the methonal. I spray the methanol laden BD into a 55 gallon drum and recirculate it while soap foams up on top. Well, I was doing this last night and grabbed my trusty gas meter. You can imagine my surprise when I pegged the meter at 50,000 PPM! I quickly went to my basement and tripped the breaker for the shed that my equipment is in.
In my own defense, I have a conder nearly completed and attached to my appleseed. I just haven't had a full day to watch it and figure out how well it works to start using it. However, I will shortly be pumping my 50 gallons of methanol laden BD back into the reactor and using the condensor to recapture it.
The moral here? DO NOT EVAPORATE METHANOL FROM FRESH BD INTO THE AIR IN AN ACCELERATED FASHION! I had a pretty good headache from just a few minutes of exposure at these levels. Some Baileys and Beer cleared it right up (not together).
I also discovered that my method for getting methanol from the 55 gallon drum into my 30 gallon holding tank releases very little methanol. 500 PPM's at max, which by OSHA standards is safe for up to 15 minutes without a fresh air apparatus.
also, outside my shed (the door was open) the methanol levels were still explosive.
As requested by Girl Mark, more info on GL's 1-day process.
It is simply one of many ways to clean your raw biodiesel before using it.
I do a one-stage base reaction like normal. After settling (1 hr if I used 5% pre-wash, 12 hrs otherwise) I drain the Glycerine.
GL's 1-day works on the theory that soap is not soluble in Biodiesel, but is in methanol. So we have to remove the methanol. Originally, this was done by spraying the biodiesel in much the same way one would spray biodiesel to remove water (a la evaporation). This produces and enormous amount of methanol in the air, even at cooler temps (my biodiesel was around 50F when I measured the gas levels).
NOTE: THIS IS NOT THE RECOMMENDED FASHION FOR EVAPORATING METHANOL
It was stated very early on after GL first published his work on this subject that evaporting methanol to the air is bad in many ways and it was subsequently replaced with a condensor, which I will be using from now on as well.
The condesor is quite easy to build and use. http://biodiesel.infopop.cc/eve/forums/a/tpc/f/44410893...861011171#6861011171
GL's 1-day process: http://biodiesel.infopop.cc/eve/forums/a/tpc/f/719605551/m/9721044051
(does this ever fall off of the 1st page?)
I'll post pics of mine at a later date.
can you tell us more about your meter? I am thinking I might get one just for safety. Its EASY to justify safety gadgets.
I originally posted about it here
However, I can't get the original linke to open the site where I bought it. It's a hand held gas detector with a goosneck sensor. It's a JL268 model. Googling that model number only brought up some chinese suppliers and a place in Australia that sell it now. Works great though and has rechargeable batteries.
the link is working now!
Does anyone know if a Combustible Gas Detector that is supposed to detect propane and natural gas will also detect methanol vapors?
The condensor looks like a great idea. I am just beginning to process bio-diesel, and have had great success so far.
How much success is there in capturing the Methanol? How much could one exspect to retain? How much water would I expect to use the cool the condensor? I was wondering what I might exspect if I tried this?
Chris, I highly doubt it.
Doyle, there are a lot of variables that will affect everything you're asking about. Do some reading and searching in the methanol recovery forum.
Out of interest, what concentration of methanol vapour do you get near the bucket, when you drain hot glycerol from the reactor at the end of the reaction?
I suspect we may find the concentration in that procedure is surprisingly high too, albeit for a comparitively short period.
However, it may show that we have another good opportunity to further improve operator safety in this step of the process, which is, after all, performed by most homebrewers, regardless of which soap removal process they use.
I'm going to stick my neck out here and propose that ALL processors should have a safe means of distilling methanol. Both from the biodiesel itself, and from the separated glycerol.
This, before any washing, whether by water or by soap filtration.
I propose we cut the term 'air-wash'. It has been superceded by distillation, and it promotes the wrong idea of what should be done.
I'd suggest the glycerol catching container has a vent back to the processor, so that any expelled fumes can only find their way back to the outside world via a condenser which acts as the vent in normal operation.
In all, we would benefit.
1. Less release of methanol regardless of the process we use.
2. Greater cost savings
3. Better performance in the greenhouse gas stakes.
Which should all add up to us having more clout in the environmental lobby, healthier working environments and fuller pockets.
I'm going to process some oil tonight. When I draing the glycerin, I'll take a reading and let you know.
On my appleseed, I have to open the vent valve to let air into the processor as the glycerin is draining, otherwise it gets a pressure lock. I have a polyvinyl tube attached to the valve to vent any bad gasses (or smells) the outside air. I wonder if putting the polyvinvyl hose with funnel attached to the end close to the draining bucket would create enough suction to suck in most of the vaporized methanol.
I'll give that a try as well and report back what I find.
How big and how high is your shed? What ventilation does it have?
mathematical elegance -- desired result achieved with minimal complication
cfunderburg, you may be interested in the "bag in a box" trick discusssed here:
This once again gets us into the subject of the whole point of the Appleseed design. It is sealed for a reason - to prevent methanol vapours from excaping into the vicinity of ignition source and the operator/bystander's lungs.
The method I use for high concentration methanol environments it to get a medical oxygen setup with the face mask and small tank and fill it with fresh air using a compressor.
Medical oxygen takes a doctors prescription but the equipment is easy to get from ebay and other sources. It so easy to do this and is very light carry with you.
I tried GL's process and had good results but it has been a very wet summer and I kept getting water in my biodiesel.
Bottom line, the water wash is so easy and I have all the water I could ever want. The extra water from my spring goes into a pond for my many fish species and the wash water from my biodiesel production feeds the microbes in my septic system.
walk softly, leave a small footprint and a big impression
Here's a quote from an older EPA ChemFacts document (http://earth1.epa.gov/chemfact/s_methan.txt):
"One worker died from exposure to vapor ranging from 4000 to 13,000 ppm over 12 hours (ACGIH 1991). The concentration of 4000 ppm is roughly equivalent to a total of 1140 mg/kg over the 12 hour period."
The NIOSH IDLH (Immediately Dangerous to Life and Health) concentration for methanol is 6,000 ppm. At 50,000 ppm you could quickly get a lethal dose by inhalation. Prolonged exposure to lower concentrations could cause vision loss.
The OSHA PEL (Permissible Exposure Limit) is 200 ppm.
See also http://www.cdc.gov/niosh/idlh/67561.html and http://www.cdc.gov/niosh/npg/npgd0397.html
Also, 50,000 ppm is about 87% of the LEL (6.0%) so fire and explosion are a real danger.
Methanol can have significant aquatic toxicity also, so indiscriminate disposal of wash water and glycerol waste streams may cause environmental harm.
With respect to air quality impacts, methanol is an EPA-listed HAP (Hazardous Air Pollutant). If you, as a legitimate business, emit more than 10 tons/year (i.e if you emit as vapors the equivalent of about 3000 gallons of methanol) you are considered a Major Source and are required to have a Title V permit, which includes paying significant annual fees and all kinds of regulatory bureaucracy.
The bottom line: The way many home brewers handle methanol is biodiesel's dirty little secret. All the good public opinion and positive press that have been earned from the beneficial aspects of biodiesel could easily be wiped out by stories of fires, explosions, blindness and poisoning, and environmental damage caused by irresponsible operators.
My 2 cents,
1986 VW Golf 1.6NA
2003 VW Jetta TDI Wagon
There is some risk in making BD, but to shun the practice altogether may be going too far. One simply recognizes the risks and takes precautions (safety and the environment) -- much the same way you should when you use a welding machine, table saw, gas grille, log splitter, lawn mower, snow skis, motorcycle, chainsaw, air compressor, automobile...
Don't get soo defensive. brbd is not shunning the practice of making BD, he is only shunning the practice of
and this is something that should be of great importance to all BD producer no matter what the scale. The idea that if your just putting out a little bi-product it's OK to dump it down the drain doesn't make much sense to me. I'm am new to the BD. I havn't maid any but I have been researching it. It seems very hard to find a responsible way of disposing of the bi-product. Everything that I have read and heard is along the lines of "dump it down the drain", and "it makes a good driveway cleaner", or "it works great to get the veg oil off your hands". Is this the way the EPA looks at it or is this the easiest way to deal with it?
The glycerin by product was a big question mark for me as well, until I began putting it into my compost pile. I clean out my mule pen, and mix it with the manure. I then spray it down with EMs (a micro-organism mixture) and cover it up. It appears to be breaking it down quite nicely. I am planning in the spring to use it in the garden.
The manure is pretty full of something like EM's all on it's own, no need to add more. Glycerine and manure is a great composting combination.
But that's a topic for the 'uses for glycerine' section of the forum, not this thread, I think.
In response to the discussion on methanol gas detectors, the following should be noted:
Methanol concentration in air can be measured using a combustable gas detector that is calibrated to a methane standard. There is a factor that the methane measurement is multiplied by to determine the methanol equivalent concentration. The factor should be included in the documentation for the detector.
These detectors work on a diffusion principle causing the reading to change slowly as the vapor diffuses through the sensor.
It is really important to calibrate the detector regularly against a known calibration standard. The standard is typically a small pressurized bottle the size of a propane bottle used to solder copper pipe. The gas detector sensor does have a shelf life and will degrade overtime - much like a smoke detector.
As probably stated earlier, the effects of exposure to methanol is cumulative and you need to be really careful about exposure even if for just a short period. With proper handling and engineering controls, The risks associated with handling methanol can be greatly reduced but the hazard can never be eliminated - so be careful.
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