element for a 120litre reflux distiller

[pete_nz]

hi how much watts would i need to distill 75litres of wash?

[LeftLaneCruiser]

ONE

and A LOT of patience


KJH

[LeftLaneCruiser]

But seriously Pete,

Since you don't give more info the question is hard to answer. Like: how fast do you want to make a run etc.
More power is faster run, but also depends on column size..

Lots of info here on homedistiller, also calculators. So: read the site and get wise.

KJH

[Grayson_Stewart]

Pete,

I could be wrong, but I think that LeftLane's comment was meant in jest to point out that you could use just about any wattage to BOIL a wash. The problem with the originally posted question is that you want to know what wattage you need to distill a certain volume. As we in the "know" know, that is a complex question that can't be answered without additional information like column size, desired rate of collection, desired cuts, pot still vs. reflux, etc.

Prior to reading LeftLane's comment, I started to post a simmiliar comment when I originally read your post...but I refrained because I didn't want to get into a discussion of all the above mentioned criteria for estimating the heat input for a particular situation....we've all covered this a buncha times and constantly re-direct folks to read homedistiller.org.

THM's suggestion works great and will serve you well as long as you invest a little research in the safe operation of a still with an open flame and how to put out a possible alcohol fire.

[DBM]

pete_nz;
I have a 20 gal pot and cook with gas. My gas stove is rated at 15000 BTU's. It takes almost two hours on high to bring the wash up to temp then about seven hours on low to make the run.
I'm not sure but it seems like someone on one of these posts tried to bring a wash of about the size we have up to temp with a 1100 watt hotplate and after four hours gave up.

[pete_nz]

My Reflux is about 6 inches wide and about 30 cm tall and inside it is filled with about 1/3 with marbles and pot scrubbers

the still use to be a 25 litres but just got it made into a 120 litre with a 1500kw element still on it, but i will need a bigger element , im not sure what kw range i will need to heat it up , im not too worried about the time it takes as long its under 10-12 hours

[Grayson_Stewart]

The following is an example of how to calculate the theoretical boil
up time for 10 gallons of water. The example uses two internal
elements (discussion of propane is below), simply insert your assumed burner W in place of the
elements:
*********************
10 gallons = 36,291 g
1 cal = 1.163 x ee-6 kilowatt hour
1 cal is needed to raise 1 g water 1 degree C.
Using 1500W and a 3800W element = 5,300 W or 5.3 kilowatts

Raise 36,291 g of wash from 21 degree C to 78 degree C
36,291 g x 57 degree C = 2,071,836 cal needed.

2,071,836 cal x 1.163xee-6 kilowatt hour / 1 cal = 2.409 kilowatt
hour

2.409 kilowatt hour / 5.3 kilowatt = .45 hour or 27 min.

************************************
This is strictly theory and it will take longer to reach boil temp
due to losses to environment, heating the boiler itself, etc. Takes me about 40 min to reach boilup on 12 gallons

It would be difficult to directly calculate the magnitude of your
burner because of the losses and no way of knowing the extent of
those losses. If using propane, The boilup can be calculated with and without losses, but you can pretty accurately determine the magnitude of your propane burner prior to making a second run.
Weigh the propane cylinder as acurately as
possible before and after the run and record the time spent with the
burner on a particular setting....high for example during the boilup phase.

[Change in weight of cylinder in kg) times 12.9 KWh/kg divided by
time in hours on a particular setting.

This should give you the KW of that particular setting of your
particular burner. Would be more acurate with good scales and
averaged over a couple of runs.


You can then record the actual power and time it takes to reach
boil temp in your setup then back through the above calculations to
determine the amount of energy wasted to losses, ie. the energy to
heat a 15 gallon stainless keg should be the same each time.

After determining the energy losses plus the energy to heat the
water you should be able to determine the magnitude of the burner.

If you wanted to get really close, you could also well insulate
everything and then follow through with the earlier diescription,
but also calculate the energy to heat the amount of copper and
stainless in the setup.
*****************************************************************
specific heat of stainless steel=0.5 J/g C

specific heat of copper = 0.385 J/g C

mass of copper or stainless X temperature change X specific heat =
Joules

Joules divided by 3600 = Watthour

Watthour times the duration to boilup = Watts used
******************************************************************
Everything else is heat wasted to heat your kitchen, stovetop, etc.
Of course you wouldn't use the condensor during this boilup because
that would draw out additional heat. This is only critical on some types of stills and I would definately stay there watching a still that you do not have the condensor on so you can turn it on as soon as you reach boil temperature.


If I didn't explain this well just let me know, I was in a hurry.
Hope it helps.