Immersion chiller

[BigYin]

these days they call us Analyst Programmers :wha:

Same blasted job I started 10 years ago when it was called Software Developer

Anyway, BTT - without any fancy engineering knowledge, most things have to revert back to "a little knowledge is a dangerous thing" :lol: So you see what others have done, guage if in your own opinion that seems to work, or could maybe be tweaked, and then have a go yourself.

On such a basis are the fortunes of B&Q, Homebase and Screwfix, among others, firmly founded :thumb:

 

[Tony]

I checked with our science dept... seems what Aleman said is spot on - that as long as the temp of the water exiting the pipe is lower than the temp of the wort, cooling will be constant.

I was shown a graph n'all ... but I fell asleep!

 

[ano]

I'm pretty sure similar discussions have been had, hence my comment about triple coil chillers.

The issue is that if you cool 90C hopped wort with 15C water it won't take that long a pipe for the coolant to acquire all the heat it's going to. Having more pipes of smaller bore won't necessarily speed up the process but may help in terms of homogeneity.

Again (my apparent misuse of thermodynamic terms aside) I wonder what we're driving at here. There haven't been any quantifiable or justifiable improvements over the variable flow rate single coil chiller thus far in the thread.

 

[Good Ed]

http://www.thehomebrewforum.co.uk/viewtopic.php?f=36&t=12763

just scroll down to Vossy's post, more wisdom :thumb:

 

[richc]

these days they call us Analyst Programmers

Dah, you got to be an Analyst Programmer, that was my first and one of my best, job titles (OK I persuaded one job to call me an Internet Guru for a while).

 

[ano]

http://www.thehomebrewforum.co.uk/viewtopic.php?f=36&t=12763

just scroll down to Vossy's post, more wisdom :thumb:

I'd say most of that ground has been covered here. I mentioned "disturbance of laminar flow" i.e. "turbulent flow", although I admit I was referring to the coolant rather than that which is to be cooled. Agitation of the hopped wort is, as far as I can tell, a given if you want to improve efficiency of the cooling system. The most telling point is:

"I also made a 4 coil IC, each coil having it's own separate feed. I didn't really see much benefit to this"

Are we writing a book here? Otherwise I'm not sure what we're discussing that can't be covered by using the search function.

 

[Alan Robinson]

Interesting reading. I am convinced no matter the flow rate, the flow will become turbulent somewhere along the line, though I doubt turbulence will affect the cooling significantly. Industrial coolers are supplied by pump and nobody seems to care about turbulence there.

More significantly though, I came across this; http://www.craftbrewing.org.uk/technical/hazes.shtml


The rate of cooling of hot wort to pitching temperatures has a profound effect on the amount of cold break (protein precipitate) formed. The ability to chill quickly is a major area of difference between homebrewers and commercial brewers. One study described results in which the best cold break formation was achieved by cooling the wort from 60 C to 21 C in 3 seconds or less. A second study claims that it is necessary to cool slowly over the range 49 C to 26 C to achieve maximum cold break formation and recommends an optimum chilling time of 30 seconds. What can be clearly seen is that homebrewers are at a significant disadvantage in chilling beers when compared to commercial brewers.

Several studies show that cold wort filtered through cold kieselguhr results in very stable beers. In general though, studies show that the raw materials and brewing factors are much more important to the colloidal stability of the beer than the degree of removal of cold break

It seems we are making the best of a bad job. Never mind.

 

[BigYin]

One study described results in which the best cold break formation was achieved by cooling the wort from 60 C to 21 C in 3 seconds or less.

:shock: :shock: :shock: :shock: :shock:

It seems we are making the best of a bad job. Never mind.

That's probably true of homebrew in general vs a commercial setup - but the gap is narrowing, gradually :thumb:

 

[commsbiff]

Am I right in thinking then, if we want to cool the wort as quickly as possible, a CFC or heat exchanger would be the best bet by far? Even in a whirlpooled IC system, you are gradually cooling the entire batch over say 20 mins. With a CFC or HE, although to cool the entire batch will take a similar amount of time, the cooling of the wort passing through the cooler will happen (relative to IC) very quickly indeed - and close to this 30 sec time mentioned above.

The main issue I see is that if you want to clear the cold break with the hop bed, you'll need to transfer cooled wort to another container before going back to the emptied boiler.

 

[Aleman]

CB you are basically right. . .And this is what Commercial breweries do . . . Wibblers has a Cold Liquor tank (Glycol Cooled to 6C) which they pump liquor through the big Plate Chiller to the HLT. . . Wort obviously pumped to the FV . . .but they don't worry about cold break . . .or hot break . . it all goes into the FV unless it gets trapped by the hop bed. . . . After 24 hours if the yeast cap is particularly dirty they skim and discard it . . . it soon reforms.

As home brewers there is a lot of worry about the break getting through . . . in a commercial craft brewery they just don't worry about it.

 

[Alan Robinson]

Aleman. I like the mention of skimming. It seems to me skimming in the FV is somewhat overlooked. I am personally keen on it. Perhaps not surprisingly, the skimmings from a brew made with syrup are of different consistency to my own all grain brews, and this can really only be down to the treatment of the wort before fermenting.

Anyway, just as I look down my nose at pedigree dog breeding - I much prefer a good greyhound / collie cross personally - who says ale has to be clear as a glass of tapwater? Okay, if we are entering competitions and being judged against subjective standards, fine. I am happy though to simply get myself a decent glass of ale at a decent price, and have fun making it.

 

[jebrug]

I have just constructed a twin coil chiller by following instructions on this forum, and found it a quite straightforward task, although one problem arose when trying to find a suitable former for the outer coil. Ended up using a redundant cherry tree which I chopped off 4 ft from the ground
BTW I am a retired architect and am now happy to know nothing about anything :)

 

[BeerBloke]

CB you are basically right. . .And this is what Commercial breweries do . . . Wibblers has a Cold Liquor tank (Glycol Cooled to 6C) which they pump liquor through the big Plate Chiller to the HLT. . . Wort obviously pumped to the FV . . .but they don't worry about cold break . . .or hot break . . it all goes into the FV unless it gets trapped by the hop bed. . . . After 24 hours if the yeast cap is particularly dirty they skim and discard it . . . it soon reforms.

Our hop bed captures the hot break, we get crystal clear wort out of the copper. The chilled wort is also clear as it is sprays into the FV. The cold break soon forms but by that time we're pitching the yeast. On the big plant we have a very clean yeast head that we don't bother to skim. On the small plant we do get some trub through so we skim that.

The quicker you can chill the wort the better, as a homebrewer I soon switched from an immersion chiller to a homemade CFC one. Our plate chillers are just more efficient versions. Plus as Tony said having a 20bbl source of 4-6 degC water helps too!

 

[BigYin]

I have just constructed a twin coil chiller by following instructions on this forum, and found it a quite straightforward task, although one problem arose when trying to find a suitable former for the outer coil. Ended up using a redundant cherry tree which I chopped off 4 ft from the ground

good work jebrug :clap: :clap:

Looks like a very nice job you've made of that :drink:

 

[Springer]

Like the post J, looks a good chiller.
Those saw horses look like they have seen life, not seen any for ages with such maturity, shame work mates took over.

 

[jebrug]

Thanks for the compliments men, I could admit to being quite pleased with my chiller effort. With regard to the saw horses, I have had them for something like 50 years, and they were second hand then. The workmates you see in the photo's were inherited from my 94 year old father who passed away last year, and they are not a patch on the saw horses for both stability and ease of use. BTW, I have now acquired a new 45 Lit cool box, which should arrive any day now, so I appear to be creeping inexorably towards my first AG brew.

 

[Cussword]

I'm rather glad I don't have a water meter, this has all gone way over my head :wha: It's my age y'know

 

[Alan Robinson]

so I appear to be creeping inexorably towards my first AG brew.

I started AG recently, and I have to say it is a totally different kettle of fish to opening tins. Glad I did it now, and it occupies my time - I've plenty of that now - getting the details right. This business of the cold break and cooling rates is particularly interesting. It has occurred to me that I can get an old refrigerator from recycling and perhaps convert that into a very effective shock chiller :wha: . That's a project worth looking into if the cooling rates I can otherwise achieve are insufficient.

By the way, I get a bit of shock cooling for the cold break by calculating the difference between the volume of hot wort I have, and the fermenting volume. I put the right amount of cold water into the fermenting bucket before the hot wort goes in; that way some of the hot stuff gets cooled very rapidly.

 

[Aleman]

Most fridges and chillers are unable to deal with the 'total amount' of heat contained in a batch of wort. The really effective way to chill using a chiller is to cool a batch of liquor down to 4-6C and then pump that through a very efficient plate chiller (Wort going the other way) of course. You can effectively chill 18BBL of wort with 18BBL of cold liquor very quickly (The time it takes the wort to pass through the chiller).

What is important to remember is that to go from 100C to 35-40C is relatively quick (delta T is High) . . . even with an immersion chiller, but as the temperature of the wort gets closer to that of the coolant the chilling effect is lessened (delta T is low). In order to retain effective chilling it is at this point that you need to increase delta T (by chilling the coolant), either by an additional coil in a bath of crushed ice (with a pump to recirculate the ice water), or an additional plate chiller connected to a bar chiller or a chilled pumped reservoir. Of course at the moment where the groundwater temperature is so low. . . chilling should not be that much of a problem

 

[pjbiker]

Just my twopenneth. Very interesting reading, despite being discussed alot before. The 'cooling quickly gives more precipitation of cold break' statement is why I spent some considerable effort making my own counterflow chiller. Though I have seen very clear results from many on the forum who use the immersion chiller method.
I also discussed the, 'cold break in the FV' issue with a 5BBL brewer. He clearly doesn't worry about it either. Re-skimming, he says cold break comes out with the first crop of yeast he skims, and he has to skim as the size of his fermenters means the yeast escapes all over the floor if he doesn't, particularly with dark beers apparently. He puts that down to higher nitrogen content in darker malts :hmm: .