Making lard liquid.

[Ivan]

Currently, this is my holy grail. I have several hundred litres of waste 'prep' - a solid form of vegetable oil. It represents most of our heat requirement for the winter, if only I could burn it. I have two choices - either heat the fuel tank and the fuel line (need some of frotter's electric fuel line heater, wherever that comes from), or I mix it with something to lower its boiling point.

I've tried methanol (I happen to have a lot of that). Surprisingly it is very difficult to mix, and it certainly doesn't dissolve. More like it forms an emulsion. I presumed due to my biodiesel experiments, that it dissolved fully (but the lids securely ON when the methanol is added, so I've never looked). The emulsion formed, even with 20% methanol added is definitely runny, but not as much as WVO - more like runny honey, which I'm not sure would be ideal for my rayburn's peristaltic pump.

Has anyone ever tried this? It would save me a lot of experimentation if I knew what does or doesn't work. I've read of petrol being used at around 2%, but it was written second or third-hand, so I'm not sure how reliable the source.

Unfortunately, with nighttime temperatures of -4C or lower each night and heavy snow to maintain the low temperature during the day, my biodiesel has frozen and even some of my veg oil, so I'm running out of liquid fuel!

[EccentricAnomaly]

Do you know anybody who can get hold of a few of those evacuated tube thingies?  Could they be used to warm the lard up?  I'm thinking a tray round a normal manifold with insulation on the outside.

[guydewdney]

I have a non scientific reason behind my memory/belief that you would have to heat it first, then mix it with whatever - rather than trying to mix cold.

[Countrypaul]

I think the fatty acids used for Prep are much longer chains than found in the common oils such as rapeseed or sunflower etc. As such this nearly always means a much hihger melting point as you are finding. The natural oils/fats are triesters of glycerol whereas biodiesel is the methyl ester thats why you transesterify the oil/fat to make bio and get the glycerol as by product. Biodiesel being a methyl ester is much more soluble in methanol than any triglyceride you will find from oil/fat.

You could try using a much stronger solvent such as acetone or isopropyl alcohol to dissolve the fat/oil (that is why they are used for titrating when making bio).  You could use biodiesel to dissolve the oil/fat as that also works - the problem is likely to be temperature. Many biodiesel makers find that longer chain methyl esters such as methyl stearate precipitate out of the bio as the temperature drops close to or below 0C.

Not sure what you intend to do with the methanol/prep mix (or acetone/prep mix etc), but if you intend to burn it then be very very careful any spillage could lead to severe problems. Methanol burns with a colourless flame so if it catches fire you will not see it (unless its dark I suppose) and may not realise until you have more serious problems. Acetone and ipa whilst not quite as bad are also not that suited to burning easily with oil/fat.

The best solution would be to heat the Prep up and mix it with liquid waste oil (rapeseed/sunflower/etc) or bio to create a more easily handled source of energy. If you go on the biodiesel forum (vegetableoildiesel.co.uk) and search you will find many discussion items about how to melt various fats such as prep/palm/animal fat etc. If the pre is in tins (rather than the plastic buckets) you could heat the whole tin on top of a turk burner - but don't get it too hot.

You will probably need in excess of 25C just to keep the fat liquid enough to work let alone pump anywhere.

HTH

Paul

[mespilus]

Track down your local AA/RAC operative
and
find to which garage/workshop they take
the cars that have suffered a mis-fuel.

Hopefully the garage/workshop will be only too glad to get rid of it to you.

The petrol/diesel mixture works better than either in isolation,
but 5-10% rug (regular unleaded gasoline) is normally good enough
to keep 'liquid' uco usable at UK winter temps,

but,

your 'Prep' is probably mainly palm oil
melting point 20-30C,
before it is abused at the chipshop
and adulterated with ffa's (free fatty acids)
with higher still melting points

and

we are dealing with lower than normal tempertures.

Can you not put a couple of drums near
the veg-fuelled stove to start to thaw
like some take the chill off 'tomorrows' logs?

Guy is correct, 'melting/dissolving' solid veg fat is a mugs game in the cold.

Imagine a matchbox stood on one of its smallest faces.
It then falls over onto one of its medium size faces.
Lower potential energy, but not minimum energy.
Then it falls onto one of its largest faces: minimum energy.

Used veg 'oil' can be imagined as a multi-sided 3-d shape
where the energy states are much closer together,
virtually a continuum.

The highest melting point 'oil' goes solid first,
but normal is 'dissolved' by more liquid fractions.

Then the next highest melting point 'oil' goes solid
and there is less liquid to 'dissolve the solids.

The highest melting point oil crystals congregate
and make better nucleation sites for the next fraction to crystallise...

..and on and on.....


A couple of days at zero C and 'oil' that was liquid at say 5-10C
might need heating to 15-20C  to fully regain a liquid state,

a strange hysteresis.

Your 'prep' after a couple of days of -5 to -10C might need
a day at 25-30C to melt.

[Ivan]

Yes, absolutely right!!

Guy, I think I discovered this, as I stirred the goo. Melting it first would probably be a much better idea - but with an ambient temperature of -6C, the idea of doing so doesn't thrillme. Melting it atop the stove was considered, but unless I want to spend the rest of the winter in the garage, and for marital harmony, it had to be disregarded.


I had planned to use my biodiesel when the temperature got too low, however, when I went to use it (as the temperature dropped to -6C and much of my WVO started to gel), I discovered the barrel set solid. Even though the temperature has risen to zero since, there is no sign of it thawing - exactly as mespilus predicts. So much for biodiesel (obviously mostly from rape oil). I do have some petrol/diesel mixture given to me by my neighbour - I hadn't thought of that one - I'll give it a go tomorrow. Any idea on percentage?

I have noticed that the prep seems to fractionate on storage at low temperature. Which makes me wonder if it will do the same thing even when liqufied with a solvent. I agree, solvents in the oil aren't ideal, but if the percentage is low enough, then it's not an issue. Luckily my wvo-powered rayburn has a small experimental tank (currently around 30litres), so it's not likely to be an enormous hazard, especially at these tempetatures.

Unfortunately, the prep is in plastic containers, so heating isn't necessarily easy (and I can't see standing the tubs by the radiator being an option, somehow)

I had done a fair bit of research on the vegoil forum

[knighty]

we produce loads of tallow at work (about 5 ton a week right now, but it used to be 12ton a week before the price shot up and the big boys pushed us out of the market).... it has to be hot before you mix anything with it.... can't you mix it in your bio diesel processor ? - makes it easy to heat and to mix via pump?

is there no way you can have a tank inside the house ?   even if the fill port goes through the wall and outside ?

mixing will get to be a pain quick... and expensive when you run out of stuff to mix it with...

the only other option is the heated pick-up pipe


you could add a small heat exchanger into the hot water loop of the rayburn, then either run water through it and take that out the wall to heat the veg with, or add another small pump and pump the veg oil to the heater and back out ?   -  only problem is keeping the oil hot when the rayburn is off ?

but I'd think a wall insulated 200litre drum would stay warm enough overnight to be good enough ?  - or an old central heating boiler.... which would make it easy to heat the oil with water...

there's be the extra electrical load for the pump.... but it should be less than the heated pick-up pipe uses, and give a lot more heat ?

[Philip R]

EA,

You have let your standards slip. What is an evacuated tube thingy??

Philip R

[frotter]

Ivan - not sure what your exact situation is re where the heated tank needs to be. My experience with solid Lard (of many types and colours!) is that above 30-40C ANYthing is runny. Runny lard is easier and cheaper to deal with than exotic mixes etc. If you can fit it in your setup, a 'lardinator' heating box of appropriate size will melt 20 Litres of Lard overnight using only 50-70 watts. Even in a sub-zero shed.





Mine is really simple - celotex boards taped around a soldered old garage-door steel box with element bolted to bottom.

I use cheap PTC heating elephants from RS

If your containers are the dreaded tubs, you could use a box to pre heat them and decant the Precious once its all luvly an sloppy. You can use heating trace/tape on lagged lines to keep it runny if it has to be outside in t'cold. All low wattage - with good insulation it works a treat.
In the cold snap Ivor's Lard has been kept perfectly runny. I was let down by the heavily anti-freezed water in heat exchanging loop and engine radiator freezing up. Could not run Ivor for about 4 days as no way to move the (frozen) water!   

Just an idea - but warm lard = HAPPY lard!



 

[Ivan]

In the forefront of my mind was the lardinator. I've copied Frotter's ideas before, and there's nothing to stop me doing so again! I was trying to remember what mistake caused the chernobylardolite accident, as this isn't something I'm keen to replicate (already flooded the rayburn with oil by leaving the pump running when the oil froze at -9.5C. Not good when it thawed!).

[knighty]

Ivan, is there no chance of building a small shed/lean too/cupboard thing against the wall of your house, insulating it and then sticking a radiator in ?

it seams like a shame to use electricity to heat all this lard.... at least hot water can come from the lard itself

[wyleu]

I've copied Frotter's ideas before, and there's nothing to stop me doing so again!

A brisk fanning down of the forum legal team, Bill, Bankit, Fiddle and Run, was required at this point.

Imagine a matchbox stood on one of its smallest faces.
It then falls over onto one of its medium size faces.
Lower potential energy, but not minimum energy.
Then it falls onto one of its largest faces: minimum energy.

Used veg 'oil' can be imagined as a multi-sided 3-d shape
where the energy states are much closer together,
virtually a continuum.

There's an early candidate for metaphor of the year!  

[frotter]

Copying, eh...?   



Yes - re the whole 'Lard roaming free around the floor' incident(s).... The usual cause is that the 20 litre cubies are very weedy. If the careless chipsop person fills them too hot they can become a tad brittle. Only takes a pinhole. Also too much bottom heat too quickly can soften the plastic too much which causes it to sag/creep and split.
This is why -
1, i use low wattage elements
2, my heater box has a sealed steel liner. If theres a leak, i can just pour it out into summat else. The element is bolted to a plate underneath the metal bottom.

If you choose a PTC heating element that doesnt go too high you shouldnt have any trouble.


A pair of these would be awesome -

http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=2995916


Using the painfully gained experiences of those of us who have chased Lard all over the floor, you should never have to suffer the same misery.....  

C'mon - we all want to see a Navvy Lardinator!

Your Lard-powered Rayburn is brilliant BTW.....  

 

[knighty]

oops, I'd edit my above post but it's too late now.....

anyway, just ignore that post, just realised it's an old post and I'd already suggested that.... don't want to sound like I'm being pushy !

[frotter]

Yes - no going back to rewrite the past now. No stopping yerself looking a complete plonker after the event.    
S'just like 1984 in here.... double plus ungood!

I expect.