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derek.duf

Baine Marie - Glycol?

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In reading various threads on here, I've seen a few mentions of using glycol instead of oil.  Does anyone have any pros/cons for this?  I have spare glycol sitting around, and assume that wouldn't put off an odor like oil would.  From what I can tell, a 95% concentration of glycol has a boiling point of 310F, so seems like it would work fine, but wanted to see if anyone has any feedback.  Thanks

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Hi derek,

 

It will work but glycol has a horrible heat transfer coefficient.  It is best not to mix it with water in more than a 40% glycol 60% water mixture or the heat transfer coefficient gets so bad that you don't really gain anything without a great deal of inefficiency.

  Steam has the best heat transfer coefficient.  We have a device called an open system presserization module that is an option with our baine marie stills.  The jacket is still an open system but up to 14 psi of steam pressure can be produced with our self contained electric heating system and the OSPM.   This setup takes a little longer to reach operating temp than running oil in the jacket but less time than glycol or hot water in the jacket.  Once operating temp is reached the still runs much like a still fired by a low pressure steam boiler.  The OSPM steam gives you a great deal more heat input than oil or glycol, with less energy input.  It also gives you a faster distilling time than oil or especially water, for stripping runs etc.  Do you already have your baine marie still?  If so, what do you have?

 

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We have a DYE still.  With a brewing background, was not even aware these type of heating elements existed!  I am not going to have a steam boiler where the still is, and may look into that down the road but looking for the most cost efficient method at this point. There's so many different types of oils that wasn't sure what to even begin looking for, so when I saw glycol I got excited. 

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On 11/24/2018 at 8:33 AM, Southernhighlander said:

Is your DYE still set up for baine marie with heating element ports installed?  If so is the jacket good for 15psi?

 

Sounds like the jacket is not rated for pressure.

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@Southernhighlander If you had a moment, would you be able to provide me some advice?  I've been doing a lot of searching and trying to figure out that best heat transfer fluid to put in my bain marie style pot, and your name seems to pop up on most of the threads and seem the most knowledgeable.  I hate asking for advice from a company that I did not purchase my equipment from, but would really appreciate and advice you could give.  Most of the heat transfer fluids I've found have to be used in a closed loop system and need a pump to move the fluid around so it doesn't burn, which I have neither of.  I've seen some threads of using water instead of oil, however my jackets are not rated for pressure so not sure if that could work.  Do you have any recommendations on specific oils to use?  This is for a 100 gal pot.  Thanks!

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Derek,

 

You can use water or oil but you must make sure that the jacket is open to atmosphere for either one.  Water will give you a slower heat up and distilling time because 212F is as hot as you can get it at sea level.  Biodiesel is the best option for a vented jacket.  It will not break down as bad as cooking oil and you can run as high as 300 F, if your heating system will get it that hot.  If using the biodiesel, be aware that it will expand as it is heated up.  I would start out filling the jacket 3/4 full.  Also make sure that there is no water in the jacket when you put in the biodiesel.  If there is water in the jacket there will be a violent reaction when the water turns to steam in the oil.  The reaction will cause pressure waves that cause the oil to squirt out your jacket vents  and cause banging noises until the steam dissipates.

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On 11/23/2018 at 11:29 AM, Southernhighlander said:

We have a device called an open system presserization module that is an option with our baine marie stills.  The jacket is still an open system but up to 14 psi of steam pressure can be produced with our self contained electric heating system and the OSPM.

Can you use cooling water in the jacket in conjunction with your OSPM? 

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6 hours ago, adamOVD said:

Can you use cooling water in the jacket in conjunction with your OSPM? 

Yes,  In conjunction with the OSPM the jacket  is filled to 15% or 20% of its volume with water.  With the OSPM, the heat up to operating temp time is less than water but longer than oil however run times are as fast as or faster than oil.   The OSPM is really great for mash tuns because you can use the jacket for both heating and cooling.  You can't do that with oil.

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HTFs are ideal, but what people found out was that the thermal mass of the HTF (Mineral oil, heavy glycol, etc), in addition to mash/wash being heated, made their already slow heat up times even worse - because they were already running undersized.  This was especially so when they filled their big fat steam jackets with gallons and gallons of additional liquid for the little elements to heat.

The other factor to consider, is the thermal mass of hot HTF means that you need to anticipate your heat input changes far in advance.  If you were used to driving a still with immersion elements, this is a big difference, because it's like piloting a cruise ship vs a speedboat.

I  know a local place that uses a circulated hot oil system, they use a massive 3 phase 480v circulation heater and their tanks have coils.  They make asphalt sealer, steam can't get hot enough.

 

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Silk,

With Biodiesel we get a heat up time of 1.5hrs if we run 22kW for every hundred gallons and you are correct unless you are doing a stripping run the heat needs to be backed off from 300F to around 240F around 15 to 20 minutes before operating temp is reach.  The oil temp will drop fast because the cooler mash  will pull the temp down.    The heat up time on my baine marie stills with water is around 2.25 to 2.5 hrs. 

Also here is something very important for safety reasons.  If you are running biodiesel or cooking oil your control point must be the oil.  The temp probe for the PID must be in the oil.  If you use the mash temp as the control point you can get a run away heating situation in the jacket.  The oil temp will reach its smoke point temp (little less than 500F) when it goes above that it will burst into flames.  As far as circulating oil through the jacket we did that with our first couple of baine maries 7 years ago and found it to be cost prohibitive and absolutely unnecessary.

Concerning my open system pressurization module (OSPM). When the OSPM is connected to the stills jacket and the jacket has 15% to 20% of its volume filled with water. The heat up to operating temp time is in between that of oil and water, because unlike a low pressure steam boiler you are starting with cold water in the jacket and so it takes a while to get up to steam, especially since the mash temp will hold the water temp down, keeping it from becoming steam longer than if something hot was in the inner pot.  Once the jacket fills with steam, she will heat fast and because the heat transfer coefficient of steam is so much greater than oil, or especially glycol, you get more efficiency and you get faster stripping run times with 245F steam than with 280F oil.  Since we are creating steam in an open system and using water instead of oil, I believe the OSPM is the best option for a baine marie.  The OSPM has an added level of safety because if your steam pressure goes above it's intended pressure, the OSPM bleeds that pressure off to atmosphere.  We also have a pressure relief valve on the jacket for safety redundancy.  As far as I know, my baine marie stills with the OSPM are the only stills out there with self contained steam heating systems.  Since the jacket is not  a closed pressurized system, we are good to go.  

 

 

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21 hours ago, Southernhighlander said:

Derek,

 

You can use water or oil but you must make sure that the jacket is open to atmosphere for either one.  Water will give you a slower heat up and distilling time because 212F is as hot as you can get it at sea level.  Biodiesel is the best option for a vented jacket.  It will not break down as bad as cooking oil and you can run as high as 300 F, if your heating system will get it that hot.  If using the biodiesel, be aware that it will expand as it is heated up.  I would start out filling the jacket 3/4 full.  Also make sure that there is no water in the jacket when you put in the biodiesel.  If there is water in the jacket there will be a violent reaction when the water turns to steam in the oil.  The reaction will cause pressure waves that cause the oil to squirt out your jacket vents  and cause banging noises until the steam dissipates.

I'd prefer to try out water first, mainly for the safety aspect.  Even if it makes the day a bit longer, feel safer at least having 1 less thing that can cause a dangerous situation.  I saw another thread where you mentioned doing some trials with water.  So best to fill my jackets up about 1/2 way with water, and obviously keep the vent open to allow the steam pressure to escape.  Then I guess just keep an eye on the water level during the run to make sure we don't go dry, then adjust the amount of water used for future batches based on how much water was left over at the end.  Does that make sense?

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12 minutes ago, derek.duf said:

I'd prefer to try out water first, mainly for the safety aspect.  Even if it makes the day a bit longer, feel safer at least having 1 less thing that can cause a dangerous situation.  I saw another thread where you mentioned doing some trials with water.  So best to fill my jackets up about 1/2 way with water, and obviously keep the vent open to allow the steam pressure to escape.  Then I guess just keep an eye on the water level during the run to make sure we don't go dry, then adjust the amount of water used for future batches based on how much water was left over at the end.  Does that make sense?

Yes, that makes sense.  For water have your temp probe in the water in the jacket down below the 5% fill level if possible.  Simple proportional heating control is best for water.  If you boil the water and let the jacket fill with steam you can get faster heat up times.  if you do run set point temp control to boil the water, set it at around 220F.

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