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giovanni
14-01-2007, 05:27 AM
Is there a major difference in using proplyene or ethelyene glycol as opposed to a brine solution in an ice rink( we are using an air cooled chiller 220 tons, 2 screw compressors with ***** as the refrigerant).
We will be closing this summer for maintenance and was curious as to the heat removing qualities of each liquid. We currently are using proplyene and considering one of the others as a cost saving idea. We were told (not by any experts in the field) that brine has a much better heat transfer quality than glycol. Any comments. Thanks

Josip
14-01-2007, 11:08 AM
Hi, Giovanni :)


Is there a major difference in using proplyene or ethelyene glycol as opposed to a brine solution in an ice rink( we are using an air cooled chiller 220 tons, 2 screw compressors with ***** as the refrigerant).
We will be closing this summer for maintenance and was curious as to the heat removing qualities of each liquid. We currently are using proplyene and considering one of the others as a cost saving idea. We were told (not by any experts in the field) that brine has a much better heat transfer quality than glycol. Any comments. Thanks

There are some regulations where you must use propylene glycol in food industry as a secondary refrigerant because that one is not poison.

For ice rink you can use any of cheap and good secondary refrigerants for industrial application. Exact difference between glycols and brines I do not know. There are some changes in density regarding working temperatures and for that reason we have to use different types of secondary refrigerants.

Best regards, Josip :)

Andy
14-01-2007, 11:19 AM
Is there a major difference in using proplyene or ethelyene glycol as opposed to a brine solution in an ice rink( we are using an air cooled chiller 220 tons, 2 screw compressors with ***** as the refrigerant).
We will be closing this summer for maintenance and was curious as to the heat removing qualities of each liquid. We currently are using proplyene and considering one of the others as a cost saving idea. We were told (not by any experts in the field) that brine has a much better heat transfer quality than glycol. Any comments. Thanks


You shouldn't need proplyene as Josip says:)

Brines are more easily pumped (less pump horse power requirements) and have a higher heat capacity per lb (specific heat capacity)
However they are highy corrosive (think what salt does to your car)
I wouldn't recomend you changing to them at this point.

What I would do is check your current mono prop concentration, most systems have either far to little (coolant maybe crystalising causing poor haet transfer or even freezing) OR there may be far too much glycol, more is not better, you will then be using too much pump power and will be reducing you system capacity because more glycol is need to be pumped through the chiller and the floor to do the same job.(lower specific heat capacity per lb, more lb's to do the same job)

Hope this helps:)

Kind Regards Andy:)

giovanni
15-01-2007, 08:47 AM
Thanks Josip and Andy.. you guys are right on the mark with what we were thinking.. especially with the glycol geling up. I also had the same opinion about the corrosive qualities of the brine solution. Thanks for the info; and we did think about having the glycol tested for percentage, guess will go in that direction. Thank you again...