Freon Gas or Ammonia

Thanks for this additional info. Because of the warmth of the climate, the compression ratio of your system will be rather high. For ammonia this might require a two-stage system, but with a suitable "Freon" choice, probably not.

What kind of condenser can you use--direct water cooled, evaporative cooled, or air cooled? This will affect horsepower significantly.

Is the production process continuous through full 24-hour days, or will there be off time for rebuilding your IBT reserve?

What has <...cost...> got to do with anything? How is the forum supposed to guess the preferred outcome while knowing nothing of local conditions and regulations from only 5 paragraphs? This is nonsense.

The mission must be to get a front-end Engineering design for the processes in question, which can only be carried out locally. If in doubt, hire a Consultant.

Cost is always a factor, so that first question was vapid. With any luck, it might be vapid enough to change the state of some refrigerant.

• The comparison will not be made on the difference in local price between ammonia and Freon, as the fluids have different characteristics that will influence equipment selection, sizing and supply that cannot be quantified here.
• If there is a policy in place that dictates Freon instead of ammonia, then the need to consider ammonia disappears, and comparisons can be made between different suppliers' equipment options that will not be evaluated here, as the decision is commercially sensitive.

So starting with cost as a primary consideration is the wrong approach.

There is no doubt that ammonia is cheaper and more efficient than the Freons, however, there are other considerations.

The main caveat is the size of the unit. All ammonia based systems involve extensive metal piping, and the refrigerant needs to be handled properly to avoid corrosion of this metal. In large installations, there can be staff that monitor operation and guard against this. A small unit might be intended for unsupervised operation, and unless a service company looks in on it every few months, problems can occur.

Freon based units are totally non-aqueous on the freon side and small sealed units are well suited for decades of unattended operation. On the environment side, the pipes must be watched for corrosion and filters on radiators changed etc.

This is why Freon rules the small situations and ammonia rules the larger ones (ships, warehouses etc)

avoiding death is occasionally a good idea

occasionally usually

I'm not into refrigeration design, so I'll presume that either could provide adequate heat transfer with appropriate design.

However, if Amonia leaked in the wet (milk) area, the batch would irretrievably be tainted. Freon would not be liquid at those pressure/temp combinations and is apparently "non-toxic".

The local meatworks here uses Amonia, since they can manufacture on site to make up for lost volumes. (Though they are processing around 200T of meat per shift.)

Now that's an OT idea worth it weight in propane.

Actually it well worth being a on topic subject. World wide over a billion phase change type cooling systems are running the stuff as their refrigerant.

World wide everything from home refrigerators, freezers and HVAC and vehicle air conditioning plus countless commercial and industrial systems are using it now.

Many developed countries have had it in their line up of refrigerant choices for over decades with many more coming online after accepting the fact it isn't any more or less dangerous than what is commonly used now and in many application sit actually far safer and hugely more efficient.

It's wide spread use is even gaining ground in the US in common applications now where it was once frowned on (never was technically illegal though) due to poorly understood and largely false safety concerns thanks to some updates to the EPA and its views on environmental plus overall nation wide energy savings.

R290 refrigerant grade propane is coming to a phase change heating/cooling system near you! (If it hasn't already and you just don't know it. )

Imagine how Gunsmoke's ratings would have soared if, every time he pulled out his gun, Matt Dillon stopped what he was doing, waved his weapon in front of the camera and explained to his TV audience that "This is a Colt .45 single action Army revolver and not, say, a banana."

Likewise there is no ambiguity as to what is meant by 'freon' as the name is commonly understood to mean a "general class of HFCs mainly used in refrigeration." Similarly for for term "crescent wrench" as understood to mean "a type of adjustable wrench."

What is so amazing to me is that somebody actually had to stop and explain this to you. Given some of your other posts, you seem to be more intelligent than that, so I'm guessing you're being deliberately obstinate. For what reason I've no idea. Possibly someone pooped in your coffee this morning and so you're now feeling an urge to lash out?

FFS, grow up.

CFC's as Well

Dear sir:

It is a very interesting question, but isn't it more important to design the chilling system for your proposed facility using a similar system as other processing facilities in your area.

Local and regional suppliers, service and maintenance teams may have to charge a higher rate if you install a one off specialized cooling system.

I think the advantage you might have over your competition would be a diversity in your range of products and steps you take to please all aspects of customer service.

Have you considered using a heat pump to cool the milk? Many dairy farms use these types of systems to bring the temperature of fresh milk down to storage temperature. The waste heat is then used for heating water overall there is a decrease in energy costs.

Ammonia would be preferable in view of energy consumption. The size of the chilling plant would be around 50 TR

That is close to my preliminary estimate, if the operation is full 24-hour days. However, if the operation is part of the day with the rest of the day devoted to ice replenishment, the TR can be less. I'm still waiting for the answer to that.

I am not a cooling expert, but have quite a bit of environmental experience and knowledge. First things first - "Freon" is a trade marked name. Be careful when throwing this terminology around, if the gas isn't coming from the name owner. We can no longer use the term "Teflon" here at work, as our polytetrafluoroethylene does not come from the trade mark owner's plant. Freon will surely be the same.

Original Freon and all the later derivatives of it to get from being a CFC to an HFC are severely limited in use by the Montreal Protocol and Kyoto Protocol. This may need to figure in your choice, as what will come in the future can only be more stricter regulations, not laxer ones.

As dangerous as ammonia is, the concern over green house gasses over rides any immediate danger to human life in this era. Kill a few outright, and save millions of lives in the future is the current motto.

Research on this Propene R1270

The simple Anhydrous ammonia VCC refrigeration has been utilized in many cold storage applications where there is a large cooling demand (in terms of tons of refrigeration.)

Due to a slightly colder expansion temperature, I also suspect that ammonia will restore the cold bank tank more quickly than could freons, based upon Newton's laws of cooling (based upon heat transfer rate being proportional to temperature difference, but when the ice tank is at specifically 0 C, the only ways to increase heat removal are (1) lower bottom temperature, and (2) more refrigerant throughput. Both of these criteria can be met by ammonia.

Also, I have seen a few ice plants (producing bag ice), that run ammonia cycle for the chilling. I suspect there is a monetary reason behind that, since no one wants to pay premium price for generic ice.

Probably too late for your friend's situation, but for heat exchangers in wine industry, they use brine tanks for storage of "cold" potential with target temperatures of -15C. The brine is pumped through a heat exchanger to achieve rapid chilling of wine/juice.

Output temperature is achieved by conrol over pump speeds (both coolant and wine).

Benefits of liquid is that heat exchange is not limited by thermal conduction through the solid phase (This is so both when chilling the coolant and in using the coolant to chill the product). The thermal expansion/contraction is easily dealt with using a floating insulation pad on the brine.