Plant Based Glycol

Allislandradiant

Has anyone experienced using a plant based glycol that is biodegradable and environmentally friendly. The application would be in a snowmelt commercial application. Also where would I be able to purchase?

GroundUp

Google it.

GGross

Just curious is the building owner just trying to be conscious about their product sourcing or do they think that traditional propylene glycol is somehow unsafe? Just for reference regular propylene glycol (no-burst for example) is going to come with "food grade" labelled right on it and isn't dangerous at all. The primary difference from my understanding between this and a plant-based propylene glycol come from the production, where plant based would use seed oils and traditional uses barrels of oil, a seed based production is generall considered more sustainable I would wager but probably a lot more expensive. I am not incredibly well informed on this so maybe someone else can correct me on these points this is just what I had gathered in my limited research when I have been asked about the glycol I sell and its safety. I don't personally know of any manufacturers selling a plant based glycol for use in hydronics, but I imagine it is available.

Regular no-burst that you use in a heating system has this noted about the non-toxic attributes

FDA Reference: "Generally Recognized as Safe for use as Direct Food Additives"

Jamie Hall

A bit to add to @GGross 's comment. Propylene glycol is, as he says, generally recognized as safe. Ethylene glycol, on the other hand (used in combustion engine cooling systems) is not; in fact, it's quite toxic.

So step one here is to realise that "glycol" is not a helpful chemical term. You need to specify which of those two common glycols you mean (there are others as well).

Then step two is to recognize that propylene glycol — we are going to assume that that is what you intend to use; at least I hope it is — is a chemical name, and what it is made from has no bearing on its chemical properties. As it happens, from the manufacturing standpoint, it's a good deal easier to make starting with one of the product streams from refining crude oil. Most of the work has already been done naturally. However, it can be made with varying difficulty from any saturated hydrocarbon. It can also be made, but with censurably greater difficulty, from some unsaturated fats, including oils from crop plants (primarily soybeans). This is more difficult chemically, and a much more intensive use of land and water (it takes a lot of land and water to grow crops than it does to run an oil well!). This it will be more expensive.

The end result chemical is exactly the same in either case.

ChrisJ

I always thought normal everyday ethylene glycol was biodegradable?

That said, what are the reasons for being concerned about being able to drink antifreeze from a heating system?

Jamie Hall

https://forum.heatinghelp.com/discussion/comment/1807719#Comment_1807719

Oh Chris! Ever read the MSDS on ethylene glycol? As it cheerfully says, short term effects aren't too bad — nausea, intoxication, abdominal pain. Later effects are total kidney failure and death… The lethal dose is remarkably small — a shot glass or so — but if caught early (within an hour) it is possible to reverse and stabilize.

It's sweet tasting. This is why antifreeze spills on your drive, for instance, will kill your pets…

ethicalpaul

it reportedly degrades faster than propylene glycol which is good, I guess, since it will have less time to poison you.

PRR

https://forum.heatinghelp.com/discussion/comment/1807719#Comment_1807719

Ethylene glycol can be burned— I did not know that, but my mechanic got a fancy burner which will eat almost anything. Mostly dirty oil, and I dunno if it burns straight 50:50 antifreeze or needs some old 10W-30 mixed in to hotten the fire.

The concern about antifreeze in heating systems is accidents and leaks. What's the worst that can happen? Murphy says it will. Prop Glycol spoils the taste but the toxicity is very very low.

Archer Daniels Midland Company is loudly press-releasing about their plant-based propylene glycol: less greenhouse and more employment. Some people think the ADM company is bad people.

psb75

Dynalene is a brand. I believe it may be corn-based.

Mad Dog_2

Uncle Richard...I've used food grade Glycerine on my fire 🔥 sprinkler system. Not sure if its suited for Heating. Mad Dog 🐕

hot_rod

The Caleff solar was a corn based, I'll check on Monday, if it still is.

As I recall it has a higher operating temperature, but not quite as good heat transfer.

Corn, cane sugar, soybeans are all used as base stock, not unlike bio-diesel.

Most all the glycol providers can offer bio based glycol.

Actually ethylene glycol is a better transfer fluid, although higher toxicity. It shouldn't be used if it can come in contact with potable water.

It's common in ice rinks and other large projects.

With one less carbon EG it does breakdown quicker in the environment. They used to spray it on planes as de and anti icers, settle it out in open bio ponds, and flush it. I think they use and recycle PG now at airports.

Glycerin must be used in PVC fire systems, it is not inhibited for hydronic use, and it gets very thick when cold. We had to use positive displacement gear pumps to handle it in the winter.

Jamie Hall

Just to add a tiny bit to the above, as non-chemical types may get confused. Glycerin (or glycerine or glycerol) is NOT a glycol. It's non-toxic; all the glycols are to varying degrees.

PC7060

Founds the links below interesting reads re use of glycol and glycerin as anti-freeze in fire suppression pipes. Both are flammable when used in concentrations exceeding following %.
Glycerin > 40% concentration
Glycol > 50% concentration

https://blog.qrfs.com/145-tycos-new-lfp-antifreeze-meets-nfpa-listing-requirements/
https://blog.qrfs.com/107-the-use-of-antifreeze-in-fire-protection-systems/

Mad Dog_2

I used Glycerin for no risk of toxic cross-contamination...Mad Dog