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Bain-Marie Boilers

Just looking through the US website, are the bain-marie boilers pressurized?
If so what temp to they go up too?
Also @punkin do you have access to all the US gear and if you do will it come straight from the China?
(still a bit confused on how the three entities are structured)

Also interested in pro's/cons of pressurized hot water jacket vs steam jacket, do either come insulated?



  • edited August 2015

    Yes mate I have access to all SD parts and all custom configurations (there are MOQs on some parts that eclude me ordering one of each).

    I stock three size onion boilers as standard, all single wall direct immersion, but can order anything you want. The bain-maries are pressure tested and come with pressure relief valves if requested (standard on all Australian tanks from now on). There are a multitude more HX fluids that just water and steam.

    We have it drawn up by the factory as you request and once the drawings are approved then we can quote. We can either drop ship to your closest capital port or organise delivery to your door.

    We have a lovely pair of bain-marie stills being built for Hartshorn Distillery at the moment, a 500L stripper and a 200L spirit still.

    StillDragon Australia & New Zealand - Your StillDragon® Distributor for Australia & New Zealand

  • So jacketed, rockwool insulation and a nice shiny copper shell could be an option?
    I didn't mean the actual vessel for pressure, just the jacket bit.
    Do you guys do something a bit like this.
    Obviously that one isn't quite right but I think what I want is electric elements in a pressurized water jacket. I get the benefits of a steam jacket without the need to buy a boiler/steam generator or run steam and condensate lines. I'm just trying to nut out options. What are the down sides to an oil bain?

  • Downside to oil in a BM? All the downsides are with water. A good HX fluid is significantly safer than water, and will heat faster, requires no top off or pressure control.

  • So with oil would it be sealed with some sort of expansion tank? What are people using? My assumption would be that the biggest factor at play is the difference in temp between the bath and the wash.
    This gets close to zero with an ambient pressure water jacket at the end of a run.
    The example I put up was gas fired but I've worked with electric ones on the past. It might seem a bit more complicated and a lot more expensive but when you consider all the extra stuff that isn't required it make a bit more sense.

  • edited August 2015

    This is @Ryno's new 500L that's being built at the moment. The beauty of the bain-maries for the electrically watt challenged is that the heating fluid can be slowly heated up overnight and then the wash charged to the still when the operator gets to work.
    Time saved without the risk.


    800 x 1131 - 152K

    StillDragon Australia & New Zealand - Your StillDragon® Distributor for Australia & New Zealand

  • Open to atmo., you still need to monitor hx temp as to not burn your fluid. There is no boil risk and a good HX can run well over boiling for nearly forever. There are downsides, it's not cheap and it's slower to react.

  • Btw I need a 2" TC spray ball like in the drawing - you guys got any yet?

  • Looks good. I used to put in two spray balls if there was an agitator to avoid the shadow.

  • Using the other port for a wash temp probe

  • edited August 2015

    Check with @Smaug, he should be able to order spray balls on 2" TC end caps so they can go on the spare boiler ports. That's how we are doing the PRV's too, they'll retrofit any existing boiler.

    StillDragon Australia & New Zealand - Your StillDragon® Distributor for Australia & New Zealand

  • I do have some 52 mm balls in the house. They are not set up for a 2" ferrule though.

    Let me see what we can do.

    StillDragon North America - Your StillDragon® Distributor for North America

  • daddad
    edited August 2015

    I'll reserve the jokes about @Smaug's 52mm balls for later.

    Now to drag this back...

    I see six elements in the bottom, for 5x 5,500 watts 33,000watts...

    33,000watts brings 500L to vapor in ~74minutes, if it were direct immersion. How long for the BM?

    Cut to half power 16,500watts and run takes another ~4 hours to get pot to under 2%.
    (for stripping this could be faster, depending on PC)

    33   x 1.25 =  41.25 kWh
    16.5 x 4    =  66.00 kWh
    total of      107.25 kWh

    I know there are some inefficiencies and efficiency like slower heatup and cutting power before end of run and using therm stored in hex fluid, but does this seem close.

    Also with steam, I assume you can use the same ports, N7 for steam and N6 for drains, N5 for safety blow off and thermometer ports,...

    DAD... not yours.. ah, hell... I don't know...

  • edited August 2015

    @jacksonbrown said: So with oil would it be sealed with some sort of expansion tank? What are people using?

    The typical setup with a BM whether for distilling or catering is no expansion tank. That is taken into account by only partially filling the bath with fluid to leave expansion space.
    When using water they normally have a 0.5 bar presure release although some folks increase this to 1 bar. Check before you buy.
    With oil at atmospheric pressure you can easily get to a bath temp of 115 degC. You can get higher but need to buffer and stabilise the HX fluid for longer life.

  • Another option for the mantle is to use water and pipe the prv into the vessel. That way your getting a direct steam injection

  • sorry to reawaken this page but what is the Minimum Max temperature of the water jacket when doing a 2000L striping run? if that makes sense.. :-/

  • Min temp is the minimum temp to boil your product, taking into consideration thermal losses. Maximum temp is the maximum pressure/temp your jacket is certified to. Not exactly answering your question perse. Think I'm in the ballpark though. Roughly 100oC to 135oC for instance would be a 2bar or 200kPa max pressure. But I'm unsure what the certified rating of your BM is?

  • edited July 2018

    A fairly general approach for stripping would be to throw as much heat at your kettle charge as your PC (product hx) can handle. If your condenser capacity were optimal, then you'd likely be driving the kettle jacket to as close to 1bar as possible. That's about 247-248 F. Jacket temps.

    But there are no hard set rules for stripping speed.

    StillDragon North America - Your StillDragon® Distributor for North America

  • In Australia your BM is classed as a pressure vessel if it operates above 0.5 Bar and the resulting calculations place your vessel in the chart below in the A through to D range. If you're operating a pressure vessel and your condenser is not your limiting factor then the maximum certified pressure/temperature of your BM will be your limit. You can always upgrade a condenser, your BM however will have a design limit.


    Hazard Levels of Pressure Equipment.jpg
    800 x 445 - 85K
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