If you are making BioDiesel from waste oils, a good trick I came up with a while back involves removing as much of the tallows as possible before making the fuel. (Nothing new there....)

But this method may be--

Take a 55 gallon drum --The lidless type works well, but any open vessel to suit your quantity is good.--I used to use IBC's of 1000 litre

Nearly fill it with your waste oil, and minimise the water and crud when filling.

Add to this, 10-15% Undemethed Glycerine from a previous reaction, and stir the whole lot up for a few miniutes--There is no need for really strong mixing--Just give it a good stir--It works better if its not really beaten up!

Leave to stand for around 2-3 days undisturbed, then using a syphon or pump, draw off the veggy from the surface down, It may be a little cloudy but will soon clarify as you heat and dry it.

You will find that the remaining tallows in your oil will have settled to the bottom and have become much whiter/gloopier than usual, and tend to stay put when you draw off the oil.

If you are using WVO/SVO as fuel, Leave a few days longer to stand in the open vessel as this will help the oils clarify and become completely clear of any moisture/methanol from the glycerine, before your usual filtration--You may find your filters may not need as much cleaning as with untreated oils.

The Glycerine will settle out in the tallow layer where thy make the fats stickier....

Titrate and react/wash (Cold Water) as normal, and your BioDiesel will have a much lower gell point/CFPP than it would have if you had used the oil without pre-treating as above...

I have confirmed by Laboratory Testing, that the CFPP using this process from Waste-oils (which I reckon are mostly Rape etc, contaminated by animal-fats and other tallow types) easily gives a BioDiesel with a Minus 10 Deg C CFPP, BEFORE any additives are used.........

Enjoy!

H.C.II, At-- BioDiesel Winterisation Divn, SWC

So will this work with partially hydrogenated oil that is a slurry at 50f.

Ian

It works with straight veggy oils, that were originally clear liquid oils at room temp, like Canola/Rape/Corn etc, contaminated by animal fats from chicken, sausages, meats, etc.etc. from cooking

Best give it a try on a two litre sample, then do a Dr Pepper test batch of a litre to see, how it turned out........

If your oil is very gloppy at those temperatures, it may be better to warm it to the point its just completely runny before treating, You can leave to cool as soon as youve finished mixing BUT dont go any hotter than is needed to just liquify the oil, Ive tried the process by heating the oil to 40 degrees C, and its not as successful for some reason........

Is it required that my glycerin contain the excess methanol, or can I use the stuff that comes out meth free from the still? I guess I'm asking what your experiments were like, with, without, gel point depression and so on. I don't doubt you, just want more detail.

I see an experiment coming on...

Finest regards,

troy

why not just dump a .99 cent bottle of methanol into your diesel before you put it in your vehicle?

quote:

Originally posted by Dogma:
why not just dump a .99 cent bottle of methanol into your diesel before you put it in your vehicle?

Methanol can be corrosive to certain metals, like aluminum. There could be expensive precision aluminum bits in your fuel system. Most manufacturers of diesel engines prohibit the use of fuel additives that contain any alcohol(s). Also (and more importantly) methanol is not especially good at lowering cloud point and gel point compared to kerosene, which your diesel engine likes much better. And when it gets down to 4F, I promise you, a .99 bottle won't be enough. In a gasser, your solution works wonders as gas line antifreeze, but in a diesel, it's a non-starter. Gasoline never gels at normal winter temperatures, but diesel does, and biodiesel even more so. "Heet" fuel additive was never intended to help with gelling/waxing issues in diesels.

Finest regards,

troy

i actually meant to say isopropyl - but, it was the end of the day and my brain was foggy.

Good points though in general.

It would seem the best recommendations involve changing the viscosity of the fuel. This can be done by either through the use of an additive, or, by cold filtering the biodiesel until there is no "gunk" at the lowest expected operating temperature.

This idea came to me quite some time ago, borne out of an accident--As some good discoveries sometimes are--

What had happened, is that I had just finished a batch of 1700 litres, and was pumping the glyc from the reactor to the meth recovery--BUT there was already glyc in the recovery unit--It had been wrongly sized for the reactor and should have taken two batches of glyc, but would only just do it if only 1500 litres of oil were reacted.

So that I didnt overfill the recovery, I bucketed around 100 litres in cubies ready to decide what to do with it at a future time, and carried on with the process.

Of course, the glyc got mixed up with an incoming pile of cans/cubies containing WVO ready for sorting.

One of the other workers at the time started sorting the fair oil from the crud and as you guess whole lot ended up in the gloop-tank, where it was all stirred up and a strange effect started to happen--It was exactly the same sort of effect as the first stage of cheese making--where the cheese starts to coalese together in small tiny clumps, in the clear liquid--as we watched over an hour or so, the clumps got slightly bigger and sank, leaving a cloudy oil on the surface. It was a Friday, so it had the weekend to settle out.--I was fairly convinced that the whole 800 odd litres would be junk by now......

By Monday, we found the oil in the gloop-tank very clear, and this oil we pumped into an IBC for reacting later--We got a lot of very clean oil off this, (considering the stuff that was put in the tank!) and found the fats had settled at the bottom in a very sticky gloopy and much paler mass than normal--It was practically white--It was much less inclined to move as we drew off the clear oil on the top too, which was nice.......

The answer to your question, about using De-Methalated Glyc, after recovery is I really dont know--At the time, we had more glyc than we knew what to do with, and it was easier for me to get Un-demethed glyc straight from the reactor the way things were set-up (We had over 12 tons of glyc in IBC's, and no one wanted it), and lots of poor well fatty/tallow contaminated oils in other IBC's, out back.

All my experiments involved the Un-demethed glyc, as I then knew it worked, so I used this method to recover a large quantity of oil from the cruddy fatty stuff I had in the crud IBC's out back.

I was well pleased when I found that a sample of BioDiesel I sent for the monthly analysis to O.A.S. (Oil Analysis Services) came back, which had been made from oils 'recovered' from the crud IBC's-
-Or rather the scientist doing the testing, Dan Brown, called me to ask what had I done different from the previous sample as he couldnt understand why the CFPP was the lowest he had ever seen on WVO made BioDiesel, with NO winterisers added!

I explained to Dan, what was different, in the 'pre-treatment' of the oil by the glyc, and he reckoned the glyc was somehow coating the 'fats' or maybe that there was some form of saponification going on, as I told him, that the glyc was wet, from the 5% addition of water in the reactor prior to settlement and the oil definately wasnt dry. He thought that this must conducting the tallow-fats to the bottom, therefore making the veggy oil much purer of the tallow-fats.

It was a shame really, It was Springtime when I discovered this, and the weather was warming up nicely!

All I can say, is to try this out on your oils, with De-methylated and Un-demethylated glyc, and see if there are any differences. Maybe it needs a certain amount of water in the glyc. to work--I didnt bother doing any testing, as I literally had glyc. to burn, and it was easier to get at the Undemethed!

I know this idea works, as others here in the UK have achieved good results using it, so it cant be a very critical 'reaction' as these other guys all follow different recipies for their fuel, therefore their glyc will be different too......

H.C.II, At-- Personal BioDiesel Divn, SWC

Do you have an approximate volume/gallons per batch you did. I have approx 30 gallons of demethalated solid glycerol that I can practise with. I am looking for a way to lower my cloud point and gel point CHEAPLY. I wash with Magnasol, can the glycerol be water free as water can mess up the washing cycle.

Appreciate the help,

Ian

Interesting but may I ask what you do with the mess left over, a mixture of glycerol byproduct and tallow?

Matt

quote:

Originally posted by IanTucker:
Do you have an approximate volume/gallons per batch you did. I have approx 30 gallons of demethalated solid glycerol that I can practise with. I am looking for a way to lower my cloud point and gel point CHEAPLY. I wash with Magnasol, can the glycerol be water free as water can mess up the washing cycle.

Appreciate the help,

Ian

Ive found that the Pre-wash immediatly after reaction before settlement works absolute wonders to Increase the yield, and makes washing SO much easier--Cant understand why it doesnt work for you unless you are skimping on methanol or NaOH, or time/temperature and getting poor conversion with lots of momo/di glycerides which are great emulsifiers and can cause a great loss when washing......


Starting quantity in the average batch WVO was 1700 litres on average, This was reacted with 350-370 litres of methanol and 6.5 grams plus titration which was around 2.0-3.5 variable

thus around 20% meth, and 8.0-10 grams NaOH, variable (At the higher titrations, I used to add a little more meth to be safe, say around 20 odd litres......)

Yield of BioDiesel, after Glyc-wash and full 1:2000 H2SO4;H2O wash three times, at one third vol/vol BioDiesel, after drying was around 1600-1700 litres, variable and the glyc plus pre-wash water at 5-6 % vol/vol original reacted veggy was around 400-450 odd litres variable.

I used around 10-15 % Vol/Vol of this glyc to WVO,oil for pre-treatment and purification of tallows. This glyc. before de-mething as it has water included from the pre-wash, does not solidify and remains liquid for a week or two at ambient temps, After longer it goes jelly like, but can be stirred up and becomes fairly fluid again....The de-methed stuff generally goes solid within 24 hours, in its IBC after removing from the recovery unit, and is quite firm in texture--We even used some as a bar of soap for the W/S!

--I would not advise you use this solid glyc, without first experimentation, as I doubt its effectiveness, and also as it needs heating to liquify would cool in the oils youre trying to treat and solidify probably before doing the job properly, Only experimentation will tell, I know that if you heat the oil/glyc mix during mixing then its effectiveness is reduced significantly anyway..........

For the small amount that is needed for this pre-treatment, you wouldnt be losing out on much meth if you were to drain a bit just for this purpose and de-meth the rest, just like I did.


Ti answer Matt's question, We stored the very pale gloopy tallows up and passed it on within the WVO trade as a carbon-neutral supplement for power-stations, who used to burn the stuff...They loved it as they could claim 'Carbon-Credits' by using this...........

H.C.II, At--Non Skimp BioDiesel Divn, SWC

quote:

I know this idea works, as others here in the UK have achieved good results using it, so it cant be a very critical 'reaction' as these other guys all follow different recipies for their fuel, therefore their glyc will be different too......

H.C.II, At-- Personal BioDiesel Divn, SWC

H.C.II, DO you have any links I could look at. I am going to experiment and would like to see what ratio's they are using or a smaller scale than you are.

Ian

quote:

Originally posted by IanTucker:

quote:

I know this idea works, as others here in the UK have achieved good results using it, so it cant be a very critical 'reaction' as these other guys all follow different recipies for their fuel, therefore their glyc will be different too......

H.C.II, At-- Personal BioDiesel Divn, SWC

H.C.II, DO you have any links I could look at. I am going to experiment and would like to see what ratio's they are using or a smaller scale than you are.

Ian

It was on the Goatindustries Forum, where a couple of memebers had tried this out last summer, As its quite a large forum Im not sure exactly where it is,

Best thing to do, is experiment with a couple of 5 gallon buckets of the same oils using various types/amounts of your own glyc. then you can find the best ratio/amounts that suit your oils actual requirements.

We may do things a little differently here, what with different quality feedstocks/ambient temperatures and reactors are normally different as the Applseed DHW tanks are not available here.
Its really a case of finding what works for you with what you have at hand, so experimentation is Highly Recommended!-

-Most guys here, though use around 5 grams plus titration and between 18-23% methanol, Some use the Glyc. Pre-wash method as I do, while others dont.
I now dont make such large batches, as Ive left the Cooperative where I was the plant manager, I now make 150L batches when time allows!

High compression
I am with matthew, what do you do with the mess in the bottom of the tub that has the glyc and fatty stuff?? do you try to seperate, or just use it like a batch of oil????? This sounds interesting,as here in Northern Indiana it got cold this week and i was running about 40% bio and had to change my fuel filter as it jelled up,YUCK.
I added some anti jell that i doubt will help and also 2 gallons of k1 and topped off with diesel, so far so good. Luckey i was running a fuel pressure gauge, as the truck ran ok but my fp was pulled down to only about 4 psi while on the go pedel. I know a few more miles and it would have took out the pump.
Thanks for your reply and any suggestions what to mix with the bio to avoid the kind of problems


Jammer

quote:

Originally posted by jammer:
High compression
I am with matthew, what do you do with the mess in the bottom of the tub that has the glyc and fatty stuff?? do you try to seperate, or just use it like a batch of oil?????


I stored the stuff up and passed it on within the oil recycler trade, for fuelling power-stations

This sounds interesting,as here in Northern Indiana it got cold this week and i was running about 40% bio and had to change my fuel filter as it jelled up,YUCK.
I added some anti jell that i doubt will help and also 2 gallons of k1 and topped off with diesel, so far so good. Luckey i was running a fuel pressure gauge, as the truck ran ok but my fp was pulled down to only about 4 psi while on the go pedel. I know a few more miles and it would have took out the pump.
Thanks for your reply and any suggestions what to mix with the bio to avoid the kind of problems


Jammer

The problem with commercial 'anti-waxing' additives, they are generally intended for Dino, and have little effect with BioDiesel fuels.
There is a specific compound for BioDiesel, called Wintron XC-30, which does a OK-ish job, but the filter can still wax as its basically only a pour-point depressant-

-I would recommend a little heat, maybe derived from the coolant system to the filter--Even a piece of copper pipe carrying coolant bolted to the filter head would help, as its only a couple of degrees from wax to clear fuel generally--Saves messing round with blending or expensive additives.....

If its that cold--you could try 50/50 dino diesel/BioDiesel--This normally keeps things under control for me in the past when Ive used less than great fuel!

Ugh, I had the same problem as Jammer these past few weeks... running a high mix of BD made from questionable WVO and when it got well below freezing here in PA, I've now got two dodge trucks stopped in their tracks. Working on that one...

High Compression I really like your idea and will make use of some of my backlogged glycerine in this way.

Could you clarify, are you adding the 5% water prewash while your mixer is still running in the original batch? You say "after the reaction"... for example in my 190liter batches we mix for about an hour then shut down. At this point the glycerine is already settling out. Would you add the water then, or wait to fully settle the glyc?

Thanks and sorry that I got a little off topic. This cold weather issue was a new one for me and wow its worth getting it right. I'll be biking the 20 miles to work tomorrow!

Regards,
Farmer

quote:

High Compression I really like your idea and will make use of some of my backlogged glycerine in this way.

Could you clarify, are you adding the 5% water prewash while your mixer is still running in the original batch? You say "after the reaction"... for example in my 190liter batches we mix for about an hour then shut down. At this point the glycerine is already settling out. Would you add the water then, or wait to fully settle the glyc?

Thanks and sorry that I got a little off topic. This cold weather issue was a new one for me and wow its worth getting it right. I'll be biking the 20 miles to work tomorrow!

Regards,
Farmer

I add the water after the reaction time, of 1.5 hours, in my case, with all pumps still running, and continue to mix for around 15 mins, then settle the glyc/water mix--It seems to settle faster too..........

Apparently, this idea of adding water just after the reaction time, came from Idaho State--and called the 'Van Gerpen' method,--maybe Im wrong here?

All I know, is it makes the resulting BioDiesel much easier to wash, as a lot of soaps appear to be conducted to the glyc/water mix during the last 15 miniutes of mixing before settlement. The yeild seems better after washing, probably because less is lost to soap emulsions.

Give the pre-treatment idea a try in 5 gallon buckets with various % of glyc/veggy oil and find the best % for your conditions--Make up a couple of Dr Pepper test-samples, and after washing/drying shove them in the fridge/freezer to see if it works out for you....

---Hope you get the Dodge running soon, Biking in cold weather aint much fun!

Thanks HC for clarifying the glycerine prewash steps. I am inspired to try this again, and the glycerine pretreatment of WVO, once the weather warms up here again.

The biking was actually allright... kind of rainy but the exercise does me good.

Thanks for the info,
Farmer

High Compression
WOW WOW WOW
I tried putting 5 gal of glyc in 35 gal of oil. I did it sunday morn and tonight (tue)i drained off about 2 1/2 gallons out the drain (small bung) and drained off some out the standpipe (large bung w/3inch standpipe with a nipple on top to make 4 inches, the oil was a little murkey so i drained another gal out the small bung.
I got 30 gallons of real nice oil and 5 gallons of super muddy lookin glyc and 5 gallons of the NASTIEST THICK GOOP YA EVER COULD IMAGINE!
I will not be able to cook this tomorow but can do it thursday nite...
I think i may be able to vac off some of the oil as it rises from the nasty, if it clears but 5 gal of oil is worth it if it lowers the cloud/jell point and makes better fuel.
Thanks for the tip
Now all i gotta do is figure out how to clean all the nasty goop out of the bottom of the barrel.
Next time i do this i think i will make a adjustable standpipe ie 3 in base, nipple,2 in,nipple,2 in that way i can drain off some and be sure i am not sucking any of that crap that drops, into the reactor. When i get to the top of the standpipe if it is clear down to the nipple i can unscrew the top section and drain on down that way i can quit when i get to the murkey nasty.
Thanks again i will let ya know how this turns out with the fuel.

Jammer

Great-Did you do it in an open vessel?--This helps the good oil to clear if in contact with the air.

Im really glad it worked out for you--

What Ive found for separating the oils from the gloop is by carefully drawing off oil from the top, rather than draining the gloop from the bottom--
The white/tallow-glyc mix tends to stay put providing you are carefull and dont use a pump thats too strong, Use a clear plastic type pipe to see that its the good stuff your'e drawing off

Its a weird thing the way this seems to work out, Seems to make the tallow a lot whiter than usual, indicating to me, maybe more good veggy which tends to be brown has been separated from the tallows