Brine

[chillyblue]

What specific gravity should i have if i have a system evaporating at -35C to get brine down to -25C.

[US Iceman]

If you will be more specific on the type of brine you want to use then someone can develop an answer for you.

Another possible question might also be; Is the piping exposed to lower temperatures during shut down conditions, say winter ambient temperatures?

The operating temperature is only one point where the freezing temperature of the brine needs to be considered.

[chillyblue]

Thanks!!

The salt used is Calcium chloride.
The system is a tank full of a water and calcium chloride brine mix, the mixture is circulated by a aggitator, the refrigeration evaporator is submersed in the mixture to cool it, the customer requires the mixture to be -25C

Thanks for your response

[US Iceman]

A solution of 29% calcium chloride (by mass) will provide a -45°F (-42.78°C) freezing temperature of the brine. At this solution, the specific gravity is about 1.296.

[chillyblue]

A solution of 29% calcium chloride (by mass) will provide a -45°F (-42.78°C) freezing temperature of the brine. At this solution, the specific gravity is about 1.296.

Thanks mate

But why -42.78C i was assuming that i would be evaporating at -30C so the brine should be capable of around -32C
Thanks very much for your help, response

[The MG Pony]

You want a safety margin for when weird things happen that we do not expect.

[US Iceman]

The original evaporating temperature was stated to be -35C, and I always add some margin of safety to cover unexpected operating conditions.

I might be a little high on the concentration, but did so knowing very little about what you are trying to accomplish.

Insufficient information = increased safety factors.

[chillyblue]

The original evaporating temperature was stated to be -35C, and I always add some margin of safety to cover unexpected operating conditions.

I might be a little high on the concentration, but did so knowing very little about what you are trying to accomplish.

Insufficient information = increased safety factors.

Ok

Thats great, thanks very much for your help

[Intermez]

Chilly,

Just as a matter of interest, tell me about your system. Size, application, refrigerant, etc.

Thanks, Intermez

[chillyblue]

Hi Intermez

The system is used for making ice lolly's.
A brine soultion is in a tank and is circulated over a submersed evaporator within the same tank, the brine operates at -25deg. C, system evaporates at around -32deg. C.
The refrigerant used is R404A
The condensing unit is a Maneurope MTZ160 giving a duty at -30deg. C of around 8KW condensing @ 32deg.C
Expansion valve Danfoss TES5 with a Nunmber 2 orifice cage.
suction is 1"1/8 with a 1/2 liquid line

Hope this helps

Chilly Blue

[suny]

Hey chillyblue

What is your problem? UsIceman has given the answer. The manufactured lollies are not hardened enough to remove from the moulds?

Suny

[chillyblue]

Hey chillyblue

What is your problem? UsIceman has given the answer. The manufactured lollies are not hardened enough to remove from the moulds?

Suny

Hi Suny

As you said, i do not have a problem now, it has been resolved via this forum!!!, but if you look at the previous entry by Itermez i quote you will see i was just answering his question.

"Chilly,

Just as a matter of interest, tell me about your system. Size, application, refrigerant, etc.

Thanks, Intermez