Ammonia cooling plant for margarine Kombinators

[Osar2007]

Dear Sirs. I'm going to make ammonia P&I for cooling margarine kombinators. I want to use ammonia pump system. Ammonia pumps will supply low pressure liquid to Kombinators. Do you have any expirience in such system. I think, that system will work ok, but maybe you know somethink more about mentioned system. I don't want to use flooded system, because distance between line receiver and consumer more than 100 meter and probably I will have flash gas in liquid line and system will not work good.
What do you think?

[RANGER1]

Liquid overfeed would be best as usually there is a lot of liquid carry over with CIP cleaning .
The only thing to check would be each units liquid make up .
If its a float with needle and seat , can it maintain level with lower pressure liquid make up ( may need larger orifice ) .

If you use high pressure liquid line makeup it would be better to subcool .
You also require liquid transfer system due to carry over previosly mentioned .

[Osar2007]

Liquid overfeed would be best as usually there is a lot of liquid carry over with CIP cleaning .
The only thing to check would be each units liquid make up .
If its a float with needle and seat , can it maintain level with lower pressure liquid make up ( may need larger orifice ) .

If you use high pressure liquid line makeup it would be better to subcool .
You also require liquid transfer system due to carry over previosly mentioned .

Great thanks for your reply! Main problem is float valve. It was designed for high pressure before it. If I will use overfeed system with pumps I will have no more, than 4 bars. My proposition is to replace float valve, which will work with low pressure. I think it is cheaper solution, Alternative solution is to install liquid level rod with Danfoss AKS41 as a liquid level control and install Danfos ICM valve with ICAD actuator. What do you think? What circulation should be for this system. Manufacture of kombinator doesn't know. I think circulation rate is one, but for sure, that system will work ok we can take no more, than two. What do you think?

[RANGER1]

The thing with the float is it could still work as there would be no flash gas at all
A similar thing was done on a flooded ice machine with no problems .

[Osar2007]

The thing with the float is it could still work as there would be no flash gas at all
A similar thing was done on a flooded ice machine with no problems .

Ok. I understood your point of view. Can you describe your system with flooded ice machine?
I can compare your system with my and can make a right choice.
Thanks in advance! What do you think about circulation rate? What is shoud be?

[RANGER1]

Osar2007
It was a flooded ice machine with high pressure liquid maintaining liquid level ,no subcooling .
Float on ice machine controlling liquid line solonoid in series with hand expansion valve .
Changed HP liquid line to liquid overfeed and it worked probably better than before .
Existing liquid pump had circulation rate of 4 to 1 .
I'm not a engineer but 2 to 1 would probably do .
System would'nt be liquid overfeed but simply supplying liquid to maintain level .
Any excess liquid in recirculator vessel from CIP etc would be recirculated back when needed so this vessel would have to be adequately sized .

Liquid pump would just bypass back into vessel when not feeding any liquid to Kombinators .

You could nearly use a float as a pilot line with Danfoss PMFL or similar if float was not to your liking .

[Osar2007]

Osar2007
It was a flooded ice machine with high pressure liquid maintaining liquid level ,no subcooling .
Float on ice machine controlling liquid line solonoid in series with hand expansion valve .
Changed HP liquid line to liquid overfeed and it worked probably better than before .
Existing liquid pump had circulation rate of 4 to 1 .
I'm not a engineer but 2 to 1 would probably do .
System would'nt be liquid overfeed but simply supplying liquid to maintain level .
Any excess liquid in recirculator vessel from CIP etc would be recirculated back when needed so this vessel would have to be adequately sized .

Liquid pump would just bypass back into vessel when not feeding any liquid to Kombinators .

You could nearly use a float as a pilot line with Danfoss PMFL or similar if float was not to your liking .

Thanks for explanation! I have two question. What delivery head has your liquid pump?What distance between liquid pump and ice mashine?

[charlie n]

I've done this with Ice Cream makers, they work fine. I used multi stage pumps to produce 6 bar liquid pressure.
Leave the existing float valves in place. Since there is no flashing through the valve, the capacity is fine. The float valve only allows liquid makeup to the evaporator, not overfeed so the recirculation rate is 1:1.

[Osar2007]

I've done this with Ice Cream makers, they work fine. I used multi stage pumps to produce 6 bar liquid pressure.
Leave the existing float valves in place. Since there is no flashing through the valve, the capacity is fine. The float valve only allows liquid makeup to the evaporator, not overfeed so the recirculation rate is 1:1.
Thanks for your help! So, you think, that I don't have a problem? According to manual from manufacture, inlet pressure to kombinator should be 9-13 bar. I can reach mentioned pressure if I will use pump with delivery head 120 meters. I think, that for float valve no reason not to work. However I don't know, why manufacture require such a high pressure, maybe because they think, that their kombinator have to work without pumps only with natural circulation of ammonia. What do you think?

[rvmitch9927]

The system I run uses HPL for the Gerstenbergs, which are similar to the kombinators. Also we have flooded votator systems which uses subcooled HPL, both systems run at -20 degrees F. We have quite a long run on our HPL and SCHPL lines from the HPR. Product temperautre starts at 135 and ends up 40- 45 degrees.

[charlie n]

The manufacturer's requirement for 9 bar is most likely based on warm high pressure liquid. When I installed 3 of these in one factory, I found out the model and size of the float valve and asked Danfoss about the application. They understood what I was trying to do much better than the ice cream maker manufacturer. The valves didn't need to change because without flash gas, the capacity is 15 to 20% higher at the same pressure drop.

[Osar2007]

The system I run uses HPL for the Gerstenbergs, which are similar to the kombinators. Also we have flooded votator systems which uses subcooled HPL, both systems run at -20 degrees F. We have quite a long run on our HPL and SCHPL lines from the HPR. Product temperautre starts at 135 and ends up 40- 45 degrees.

Thanks fo reply. As far as I ubderstood, you solved this problem by subcooling HPL. Am I understood correct? Did you use something like economiser???
What lenght of pipe from HPR to Gerstenbergs??

[rvmitch9927]

Thanks fo reply. As far as I ubderstood, you solved this problem by subcooling HPL. Am I understood correct? Did you use something like economiser???
What lenght of pipe from HPR to Gerstenbergs??

We don't subcool the liquid for the gerstbergs, just hot liquid. The pipe run is about 300 feet.

[Osar2007]

We don't subcool the liquid for the gerstbergs, just hot liquid. The pipe run is about 300 feet.

Îê. I understood. 300 feet it is approx. 108 meters. Isn't it? Do you have any upwards of your pipe or not? If yes, what is the maximum hight?

[rvmitch9927]

We run it through the Engine room and then to the roof, which is 30 feet above the ground. Then we drop it through the roof to each user. The votators we do use subcooled liquid, I don't know why they didn't design the gerts. with subcooled liquid. But the gerts work with hot liquid just fine. I hope I'm helping you out with this info.

[Osar2007]

We run it through the Engine room and then to the roof, which is 30 feet above the ground. Then we drop it through the roof to each user. The votators we do use subcooled liquid, I don't know why they didn't design the gerts. with subcooled liquid. But the gerts work with hot liquid just fine. I hope I'm helping you out with this info.

Thanks for your help!