hi, working on my new processor (GL Eco type) and have a question. how deep is a safe depth for the heater in the tank. i dont need a boom during demeth. i plan on doing 120 liter batches with 26.4 of methanol. for a grand total of 146.4 liters of fluid in the tank. the heaters(2 of them)are 220v 4500w hot water heates running on 110v. i think that makes them 1125w. any way they are at the 50 liter mark with 96.4 liters above them. it's around 16 inches under the fluid. thanks for any response.

Team
-heat rises, so why place them that high on the tank? Electic heaters present a safety concern for many here, my self included. I use those elements, but mine are about 6" off the bottom of the tank. be sure to shut them off before draining the tank, if not, and I speek from experiance, the bang is very very loud!!!! Tom

Because heat rises I believe you would have the best effect if they are as close as possible to the bottom of your tank.
To prevent a boom you must have a float switch or some other safety to prevent them from coming on when not covered, the depth in the tank has no impact on the heaters safe operation...
Jon

thanks guys, i understand about not turnning them on with no fluid around them.i will have saftey controls. i was just thinking the flow from the pump might aerate the fluid enough to cause a problem. i guess im just a worry wart.............the tank is a square stainless homemade job. the ellemets are mounted at the top of the cone. i could always add another inline heater for demething. ill add some pics soon.

Murphy's Machines has a float switch specifically designed for use with a biodiesel reactor. If you absolutely MUST have heat in the reactor (neither of my two has) then this safety feature is worth the investment, IMO.
HTH

Sorry guys I have to point out that heat doesn't rise. Hot air does and so does the heated portion of a homogenous mixture. The point is moot though (no disrespect intended). Heat radiates from hot to cold. I still like the elements mounted low. Above the aeration area is a good idea.

Double D
-None taken, but why then is my processor hotter higher up than on the bottom? Tom

quote:

Originally posted by Biotom:
Double D
-None taken, but why then is my processor hotter higher up than on the bottom? Tom

I don't know.
I know if you do a glycerine pretreat and have the heating element in the glycerine layer, the glycerine will stay hotter by 15F+ than the oil above it. I've seen this. It took me a few minutes to figure out why my in tank thermometer was reading around 110F and the element was off when it was set at 130F. The stat is just above the element.
If you put a hot pan on the countertop, the countertop gets hot, not just the cabinet above the pan.
From a radiant heating perspective, "Heat" radiates up, down, and sideways, in all directions. Otherwise the sun would never be able to heat our planet.

For all practical intents of this thread, hot oil will rise to the top of the vessel.
Just a bit of semantics.

quote:

Sorry guys I have to point out that heat doesn't rise. Hot air does and so does the heated portion of a homogenous mixture.

Huh?
So when does heat not rise then?
Jon

oops...
I am a slow typer and missed your last post, I see what your saying now.
I think that some things conduct heat better than others hence the difference you noticed with your example. Heat will conduct in all directions as you stated but it does always seem to conduct better in the up direction. Just check the legs on a wood stove or start a fire on the ice the next time your ice fishing to see the effect. Er maybe the latter is a Canadian phenomenon!
Cheers,
Jon

quote:

Originally posted by Jon Heron:
oops...
Heat will conduct in all directions as you stated but it does always seem to conduct better in the up direction. Just check the legs on a wood stove or start a fire on the ice the next time your ice fishing to see the effect. Er maybe the latter is a Canadian phenomenon!
Cheers,
Jon

Thats definately A Canadian phenomenon. I never have understood that one. I'd love to try it. One of these days?

Trust me, you dont need to try ice fishing, its not all its cracked up to be.
To simulate;
put fish in a bucket, place bucket in deep freeze, get drunk, get in deep freeze with tip up fishing rod with bait bucket, drink more, catch no fish, get cold and stumble home...
Now I just get drunk at home and cook the fish on the stove and keep warm!
Jon