View Full Version : Salinity of water for flake ice production

15-05-2016, 04:34 PM
I trying to find data about required salinity for flake Ice production.
Anybody know what is required salinity of water. Ice is produced onshore and used for cooling fish catch on small fishing ships. I maintain two ice-makers of 4t/24hr capacity which use STAFF rotating drum evaporators, and are equipped with brine dosing pump, but I need to know what is required salinity for correct operation of these evaporators.
Could I measure the salinity with these devices:


I am unable to find any reference about subject execept this one:

15-05-2016, 04:51 PM
Idial salinity will be up to 200 ppm but up to 500 ppm is used.

15-05-2016, 06:41 PM
Hi Chemi! Thanks for that!
What is, by your opinion, good and affordable ;) tool to measure salinity?

15-05-2016, 08:15 PM
To be honest, I have never measured it. Just used to service them for a friend and read the instructions and manuals but that was a while ago and things might have changed.

16-05-2016, 02:33 AM
Try one of those refraction scope things, similar for testing glycol.
Best manual method is a piece of flake ice and rub it on your lip and you should just / mildly taste salty, if really salty too much

16-05-2016, 07:00 AM
Hi Magoo!

What I found on e-bay are refractometers which indicates salinity in ppt (parts per thousand)! It is 1000 times less resolution than what is required for measuring 200ppm (part per million) salinity.

Minimum Division: Salinity: 0.2% (2ppt).

Therefore I asked if those TDS-3 meters of 1 and 10 ppm resolution can measure required salinity.
I suppose the way to do it is by measuring TDS before and after salination. Diference should be 200 ppm!

16-05-2016, 06:41 PM
Chemi-cool beat me to it :)

Been a while since I have worked on flake ice machines, but I found this on a North Star automatic salinity system pamphlet

It has long been recognized that the addition of a very small amount of salt to the
make-up water (100 to 400 ppm) enhances flake ice maker production and performance,
and promotes smooth machine operation.

The last North star machine I worked on had a salt tray, where they would put salt tablets that looked like hockey pucks, only smaller.
The salt tray was halfway submerged in the fresh water tray, and there was some mechanism that was activated when the ice got to hard (too much resistance on the blades), that switched the water supply from the main tray and into the salt tray, the salt tray would then overflow into the main tray, and when the ice was soft again it would go back to the main tray.
It seemed kinda makeshift, but it worked :)

As for measuring salinity, a refractometer would work the best, or a hydrometer from a aquarium store (but those measure in PPT and not PPM so you need to do some math), cheapest would be the hydrometer :)

16-05-2016, 09:01 PM
These Kiwis seem to know how to do it, see towards bottom of article for amount of ice per tonne.


16-05-2016, 11:11 PM
Big thanks to all.

It is consistent that amount is between 200-500 ppm!
0,5kg salt per 1T of ice is weight ratio of 1/2000!
500 ppm is also weight ratio of 1/2000!



Refractometer does not have resolution for these measurments. It is like measuring vacuum with regular refrigerant gauge!;)