StillDragon® Community Forum


Be part of our community & join our international next generation forum now!

In this Discussion

Tube in Tube Countercurrent Mash Chiller

edited November 2014 in General

We've been playing around with ideas for crash cooling mash to pitch temperature. This is an easier challenge if you are a liquid only operation, but if you are working grain-in, standard plate heat exchangers simply won't work. They can't pass solids, and unless you invest a small fortune, they aren't entirely sanitary.

The current thought is to build a heat exchanger that is similar in configuration to a Leibig - tube within a tube, water circulating through the outside jacket, mash moving through the inside tube.

It would be relatively easy to manufacture an HX like this out of Copper - an inner tube of approximately 1-1.5", and an outer tube of approximately 2-3". Reducers would form the seal, larger Tees on the outer jacket would allow for coolant input and output.

Easy enough to use standard 8 or 10 foot lengths of tubing, as well as 180 degree U's to form the loop backs.

This is similar to the approach used in dairy ops, only their heat exchangers are all stainless, sanitary, tri-clamp. For example, here is a huge single pass unit:


There is really nothing here that is fancy fabrication, it's just a number of leibig style heat exchangers folded back on themselves.

Technically, you wouldn't necessarily need to cool the mash to pitch temperatures in a single pass, you could recirculate from the mash tun to the heat exchanger until your temp was reached.

The challenge we're facing is how to go about this so it's at least quasi sanitary. It would mean that the U-tubes at the end of the exchanger would need to be tri-clamp, such that you could open, inspect, thoroughly clean each tube section.

I'm pretty sure it's going to be cheaper to do this out of copper than out of stainless, since you could easily use standard plumbing sizes, and brazing of tubes is going to be easy enough.

My thought is to use 4 tubes, 8 to 10 feet long, with 3 180s, so that from a connection standpoint, you start and end near each other. That should provide 16 square feet of cooling surface. The jacket tees would all be connected together to form a single jacket flow. I'd weld up a simple box frame to keep the 4 tubes secured.

Any thoughts from the crew here?

480 x 405 - 40K


  • Hello, I love the idea. You could use Victaulic on the 180s. I don't know if they make copper vic ends. The stainless vics would probably be cheaper than tri-clamp. Just throwing ideas around you could use sch 40 stainless on the inside and carbon on the outside. Tig with 309 which is for welding stainless to carbon. Using the sch 40 stainless and tigging you wouldn't sugar on the inside as long as you keep your heat down. The more I think about this the more I like it. I know using stainless is expensive but its a one time expense and you got something for life. Great idea, I wish I would've thought of it. Thanks

  • edited November 2014

    Not my idea, stole the idea, but I think I can build it cheaper than I can buy one for.


    800 x 625 - 49K
  • edited November 2014

    I've seen a few in pics of breweries done in stainless and i've seen at least one done in PVC, that one may have been a home brew one though. It was wall mounted. I'll see if i can google a pic of it up. Can't remember whether it was a magazine article or a thread on the beer forum where it was discussed.

    How would a reverse herms style setup go?

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

  • edited November 2014

    In a commercial setup, hell, wall mount it for sure, run it 20 feet down, and 20 feet back. Since the fittings are the most expensive part of this, making two long passes is going to save quite a bit of money. In addition, wall mount means you don't need to fab a stand.

    PVC is interesting, I'm wondering if you could get 1.5" sanitary pipe with TC fittings in 8 foot lengths. Perhaps there is some easy way to repurpose a rubber boot, such that you could get it over the TC fitting, and clamp it to both the sanitary pipe, as well as a cheaper PVC jacket. Then you could use standard sanitary U-bends, clamps, gaskets, and it would all break down to be squeaky clean.

  • edited November 2014

    Sure can, they're called plumb quick over here and come in multi sizes to fit all sorts of od pipe like earthenware to pvc etc....

    "plumb quick" image search @ Google AU

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

  • edited November 2014

    You know if someone still had some 2" TC to copper adapters, I'd be all set here, you could knock this out in an afternoon using those flexi-couplers, PVC, and copper. Or really, I should just keep practicing my tig.

  • I've used and can recommend the shell and tube, dimple plate etc. Monitor pressure drop and maintain a good CIP program to avoid the need to remove your inner tube for cleaning.

    At present I'm looking to install a spiral heat exchanger for another job I'm working on. Very efficient units that take up very little floor space. Check out a few of the videos on Youtube.

    Your design however, you can build yourself, thumbs-up. ^:)^

  • I have been thinking about the same setup lately. I have a few glass leibigs from my previous setup and will use them.

    Is glass an option for you? It would be very easy to setup and the parts may cost less.


  • If you are going to use 2" or 3" copper pipe for the inside pipe of the liebig then SD copper or brass ferrules would work for you?
    @captainshooch recently posted a picture of his baby dragon bling using a copper 180 and a pair of our copper EZ flanges. Use high pressure clamps for a secure connection if needed.

  • I was unaware, those are actually perfect.

  • How big are your batches? Maybe an immersion plate chiller like the wineries use. Crash to ferment temps and ferment temperature control. Perfect for fermenting on the grain?

  • 2000 liter batches.

  • I have a couple large coaxial coiled heat exchangers, planning to use one to cool backset and pre-heat the next batch at the same time... that largest is about 45lbs and has 7'8" ID tube... I think it is rated at 3.5tons/42,000btu... not sure how it would take to full mash, but it can take whole hops.... my friend has a bigger one, probably 100lbs or more, may have 1.25" ID inside tube.. I will see what scrap value is and what he may sell it for, since it is work for him to get the copper out for scrap...

  • edited November 2014

    You might be able to work something out using that approach. The 7/8ths would be impossible for any kind of pump other than a big positive displacement, a centrifugal would never be able to build up enough pressure to move mash through it, like sucking oatmeal through a cocktail straw. I can build somewhere around 60psi with the mash monster, so it might work, but moving it through 1.25" is going to be a hell of a lot easier. Hoses might be an issue at that pressure, I'd hate to be in the shop if one of those let go at anything more than single digits.

    With Lloyds recommendation about the copper TC ferrules, it would be very, very easy to build a modular sanitary exchanger with 10 foot pipe lengths and a PVC jacket. I'm about to order a couple from Larry just to play with. 2" would be easy peasy for most pumps. Even if you wanted to go above and beyond CIP, it would be very easy to take off the 180 U's and push a brush through.

    Let me know what he says about the big ID, and what the length is, it should be easy enough to compare the build vs buy cost.

  • I'm REALLY loving the sound of this project.

    The very first (to my knowledge) fully modular, sanitary shell and tube heat exchanger of its type. If you go with the TC ferrules then go for the twin nut pressure clamp option or remove the wingnut from your original clamp and replace it with a teflon hex nut. You don't want any nasty surprises.

    Prior to this thread I would NEVER have considered this as a self build option.

    Keep us posted with your progress and pics.



  • PS I did just stumble across this homebrew hobby build:


    800 x 600 - 146K
  • edited November 2014

    Really is just nothing more than a big liebig.

    Copper flange, 3x2x2 reducing tee, 10 feet of 2" and 8 feet of 3" per segment. The 180 U bends can be off-the-shelf stainless.


    Whole lot easier to deal with when space isn't the issue. Not sure if the approximate half inch gap between pipe walls is sufficient. If it's not, moving to 4 inch pipe is going to be much too expensive. Rethinking the PVC jacket, it may not work due to the liquid temps potentially being near boiling.

    225 x 225 - 5K
  • I wonder what a nice shiny SD modular system would cost ;-)

    A simple 4' jacketed 2" TC pipe with 2 3/4" TC jacket fittings could be around a hundred bucks, even with a piece of stainless strap/rod wound in the jacket like the blue wire above... design the jacket fitting length to fit a standard straight section between two of them when connected with a standard 2" 180 TC section...

    may need beefier standoff mounts to mount to the wall as a piece of art...

  • @grim,

    Think 4 courses is enough?

    StillDragon North America - Your StillDragon® Distributor for North America

  • No probably not, single pass needs a massive exchanger. My thought is to recirculate from the mash tank, multiple passes required.

  • if you could get the 'knurled' inner tube like we saw on the condensers at the ADI, it might help also... the cooling of the outer mash would happen a lot in the first section, and the u-bend should change things a bit in the flow... I think 4 4-8' sections would do quite a bit... but hey, that is the beauty of modularity...

  • another modular option would be a standard TC pipe 4-8' long, and then pipe of some sort on the outside (stainless, CPVC, ABS) that slides over it, and you have a split 2-piece fitting on each end that has the coolant fittings in it, and uses o-rings as a seal between the inner and outer tube, and some sort of seal between the halves of the end piece...

    all SD has to make and ship is the split fittings in a couple sizes for different regions...

  • As long as you don't need to do it in one pass, you can trade off cost and size for time.

  • @grim how is your mash tun heated, if jacketed is there a possibility of introducing cooling to that as well?

    The day you quit learning is the day you start dying!

    "I am an incurable gadgeteer, and I like enormously to set up a theory and then track down the consequences" Murray Leinster

  • I did a tour @ Blue Ridge Distilling / Defiant and they had this type of cooler on the wall: Check them,out or give them a call

  • edited December 2014

    It might be easier for you to keep this sanitary if you used a big shell and tube condenser with removeable end plates. A bit more difficult to build than the multi liebig option though. Multiple liebigs connected with removeable 180 bends for cleaning is no problem to build in any size.

    If this is about crash cooling are you considering using a low temperature fluid in the liebig? Glycol?

  • @grim said: I finally ordered the fittings to put our Tube-in-Tube mash chiller together.

    Care to build two? :)

    Did you go with, copper, pvc, stainless, mix, or something else?

  • edited March 2015

    Here's my proof of concept with 40" 2" copper. 3x2x2 copper is $100+ so I thought I might try this approach.



    600 x 800 - 50K
    800 x 600 - 54K
Sign In or Register to comment.