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CharlesKerr
02-03-2016, 11:27 AM
Hi

This is my first time on this forum and hopefully this is the correct place to ask this question.
I have some refrigeration experience, fridges / freezers / laboratory equipment . Built a ice-cream machine:cool:. But I've got a lot to learn + my maths isn't the greatest!

I'm designing a Pasteurization machine that needs to cool small bottles from 62 deg to 25 deg in 10 min! then to a final temp of < 4 deg. Basically there is a 20l water bath + 36 bottles in the water. The bottles total volume is 5 liters. The warming water will be drained.
Now, I want to have a refrigeration storage tank (also 20l) that I have already cooled to just above freezing, then circulate this around the bottles while still actively cooling. I need to work out the cooling requirements and what type evaporator would be best.

Any help would be greatly appreciated.

monkey spanners
02-03-2016, 06:23 PM
How about a copper coil, you could form an ice bank on it, it would give the cooling a head start.

CharlesKerr
04-03-2016, 06:35 AM
Hi.
i was thinking about creating an ice bank during the heating of the product, then using this as a thermal mass to initiate the quick cooling. What is the easiest way to create an ice bank. I'm only circulating about 35L of water.
Are there off the shelf plate coolers like those found in fridges? or would it be easier to make my own by fixing my copper coil to an aluminium place. Also for something like this, would it be easier to use a TEV or calculate the length of capillary tube required. (Which unfortunately I have no idea of how)