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Using hot water to run your still. Anyone using that?


Dehner Distillery

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I am wondering if anyone out there is using a water boiler (not steam) to heat there still.

1. Does it work ok for you?

2. What size of volume and how long does a run take?

3. how many BTU'S is your boiler?

I know a couple of people using this method and it seems to work for them. I am just wondering if anyone is doing the same.

Thanks!

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Just curious about what advantage hot water has over hot oil?

Water can't go past ~211 degrees (unless under pressure) and the oil in my jacket heats to over 350 degrees. Do water and oil transfer heat at noticeably different rates?

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We use a bain marie. Actually, you get up to about 218 degrees, there is enough back pressure for that even with 0.5 psi relief valve. And when you do that, you are partially heating with steam, depending how high your bath level is and if there are side walls around the pot. We can actually effectively steam heat by dropping the water level down below the pot, something you cannot do with an oil bath.

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Just curious about what advantage hot water has over hot oil?

Water can't go past ~211 degrees (unless under pressure) and the oil in my jacket heats to over 350 degrees. Do water and oil transfer heat at noticeably different rates?

If you were going to keep the water in there for a long time you would treat it with chemicals as you would a regular boiler. And you can get over 212f with simple additives like antifreeze.

So that was my thinking was how many people use a water boiler (not steam) because you can put additives in the water so that it would not even boil 250 or even 300° if you wanted to. Then that hot water would be moved around ( recirculated) the distillery buy a hot water pump.

It seems like a winner on paper. But I would like to see more i guess.

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I cook my corn this way, it works but not efficiently. We will be adding a jet burner to pump up the heat. The greatest exchange in Btu's appears when there is a change of state, steam vapor back to liquid. Hot oil has a huge Delta "T", difference in temp between the two liquids.

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50/50 mix of water and antifreeze (propylene glycol) will not boil till 265-268f at 15 psi. It would be the same as your car. So increase that ratio for added temp.

My boiler guy says he can get it up to 350-400f with out boiling, but I would have to think that it is something that has no water in it at that point.

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I cook my corn this way, it works but not efficiently. We will be adding a jet burner to pump up the heat. The greatest exchange in Btu's appears when there is a change of state, steam vapor back to liquid. Hot oil has a huge Delta "T", difference in temp between the two liquids.

This is what I don't get because common sense would make me ask what is the difference between 215f water and 215f steam? Like do you want to get crushed by a 1 ton cow or a 1 ton pillow?

Get what you are talking about with the "Delta T" but it would all in how good the still is set up, correct? Delta T= starting temp in, exiting temp out.....

Heavy thinking.....

Thats why I'd like to find more people out there using hot water to power there still.

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50/50 mix of water and antifreeze (propylene glycol) will not boil till 265-268f at 15 psi. It would be the same as your car. So increase that ratio for added temp.

My boiler guy says he can get it up to 350-400f with out boiling, but I would have to think that it is something that has no water in it at that point.

We went with a water/glycol heater from http://www.heat-inc.com/tempered.html.

It's a 120kW electric unit that goes to 225F with a 50/50 glycol water mix. Works well for us. One big reason we did this is to avoid boiler regulations: pressurized vessel, boiler room, boiler inspections, etc.. The fluid heater is a big immersion element and a pump that sits on a skid. Easy to hook up and use.

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There are three differences between hot water and steam in terms of heat transfer.

The first is the heat content (which was already mentioned by Mash). The latent heat given up by the condensation of the steam is large compared with the sensible heat that is available by cooling the hot water. This is on a "per pound" basis, of course when you talk "per volume" it is not such a big difference because steam is much less dense than water.

In my opinion, the major difference would be the heat transfer coefficient. Condensing steam has a much higher heat transfer coefficient then circulating liquid water. But this only affects the heat transfer coefficient on the hot side of the coil or jacket. The heat transfer coefficient on the cold side remains the same and this tends to make the difference in the overall heat transfer coefficients (including both sides of the jacket wall and the conduction through the wall itself) using water or steam less significant. But it does mean that you need more heat transfer area when using hot water.

The third difference, already pointed out by Dehner, is the temperature. Lower temperatures also require more heat transfer area to get the same amount of heat transferred.

If a hot water generator requires less paperwork and approvals than a steam boiler I would think this could be an attractive alternative to steam for a small startup distillery. The jackets or coils would just have to be sized accordingly.

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We went with a water/glycol heater from http://www.heat-inc.com/tempered.html.

It's a 120kW electric unit that goes to 225F with a 50/50 glycol water mix. Works well for us. One big reason we did this is to avoid boiler regulations: pressurized vessel, boiler room, boiler inspections, etc.. The fluid heater is a big immersion element and a pump that sits on a skid. Easy to hook up and use.

What kettle size are you using? Heat up time?

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What kettle size are you using? Heat up time?

It was designed to get 300 gallons to a boil in about an hour. We had issues with our 300 gallon stainless still and switched to a 200 gallon copper still for now and it heats it to a boil in about an hour. We believe we will get similar results with the 300 gallon once we install our new copper coil instead of using our original stainless jacket. The stainless jacket was significantly undersized and did not transfer the heat as well as we thought it would.

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We went with a water/glycol heater from http://www.heat-inc.com/tempered.html.

It's a 120kW electric unit that goes to 225F with a 50/50 glycol water mix. Works well for us. One big reason we did this is to avoid boiler regulations: pressurized vessel, boiler room, boiler inspections, etc.. The fluid heater is a big immersion element and a pump that sits on a skid. Easy to hook up and use.

Holy cow. 120kW, that's gotta draw around 400 amps? I'm doing it with 27kW and I pull 91.

(stainless still filled to around 130 gallon, oil jacketed, agitator and heatup time is 2 hours flat)

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Holy cow. 120kW, that's gotta draw around 400 amps? I'm doing it with 27kW and I pull 91.

(stainless still filled to around 130 gallon, oil jacketed, agitator and heatup time is 2 hours flat)

Unfortunately, we only had 208V 3 phase in the building so it draws about 333 amps. But that's only the heat up time, once it gets there then the duty cycle is in the mid teens. We also have no agitator.

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I would kill for 400 amps! and more space.... :)

Here is what I am thinking...... Sounds like the hot water works much as I thought. I Think I would look into a water boiler powered by NG and not ELE.

120kw is about 409,500 btu's. That would be a cheap boiler to buy. About $4000-$5000.

That sounds great.

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I would kill for 400 amps! and more space.... :)

Here is what I am thinking...... Sounds like the hot water works much as I thought. I Think I would look into a water boiler powered by NG and not ELE.

120kw is about 409,500 btu's. That would be a cheap boiler to buy. About $4000-$5000.

That sounds great.

From what I've found, the price to install a boiler is typically where the biggest expense lies.

Would there be any advantage to modifying an oil bath system to a water bath? Right now I have 27kW going into the jacket, 27kW is 27kW is it not?

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From what I've found, the price to install a boiler is typically where the biggest expense lies.

Would there be any advantage to modifying an oil bath system to a water bath? Right now I have 27kW going into the jacket, 27kW is 27kW is it not?

I am saying that it would be cheap to get a water boiler (not steam) that runs on natural gas. It would not have near the requirements need as steam does. It would runs just as hot if not hotter than steam.

You could use it on your oil bath, it would take a couple super simple mods to make it work correctly.

For me I don't have a lot of power so NG is the way I would go.

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Check your local codes before you assume that a hydronic boiler or water heater requires any less scrutiny than a steam boiler. Many jurisdictions draw the line based on the input BTU of the appliance, not the fact that it is hot water or steam. Ever wonder why you see so many boilers and on-demand hot water heaters of 399,000 BTU? The funny number is due to the fact that those juridictions draw the line at 400,000 BTU. IBC 302.1.1 for example.

We had zero issues with our steam boiler installation, I'm sure the same scrutiny would have been applied for a similar sized electric or hydronic boiler.

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Check your local codes before you assume that a hydronic boiler or water heater requires any less scrutiny than a steam boiler. Many jurisdictions draw the line based on the input BTU of the appliance, not the fact that it is hot water or steam. Ever wonder why you see so many boilers and on-demand hot water heaters of 399,000 BTU? The funny number is due to the fact that those juridictions draw the line at 400,000 BTU. IBC 302.1.1 for example.

We had zero issues with our steam boiler installation, I'm sure the same scrutiny would have been applied for a similar sized electric or hydronic boiler.

How big is your steam boiler?

Good Idea... We run a 199,000 BTU on demand water heater.

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