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Re: ammonia refrigeration
Hi :)
and you thought I was ticked off at the lack of understanding of NH3 and it's safe application :D :D
Mark C :) there is one alternative for NH3 when applied in low temperature blast freezing and that is a CO2/NH3 cascade. Higher COP lower and if required a lower evaporation. But that is the exception. If fairness to bitzer their open screws actually perform better on Low Pressure Receiver NH3 systems than can be simulated in their software. (we use them for small loads, in dual or tri compressor pacs up to say 200kW at deep freeze conditions).
Kind Regards. Andy :)
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Re: ammonia refrigeration
Quote:
Originally Posted by Andy
Hi :)
and you thought I was ticked off at the lack of understanding of NH3 and it's safe application :D :D
Mark C :) there is one alternative for NH3 when applied in low temperature blast freezing and that is a CO2/NH3 cascade. Higher COP lower and if required a lower evaporation. But that is the exception. Kind Regards. Andy :)
That is not an apples to apples comparison. :cool:
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Re: ammonia refrigeration
Quote:
Originally Posted by Mark C
Hino experience or understanding.
No??? How you determine this on a distance of some thousands of miles.
Quote:
I would much rather be in a room full of ammonia gas, than one filled with a HCFC gas!
Well, that's your decision. I wanna live some longer.
Quote:
First, you do NOT bleed from the mouth or nose after being exposed.
Hey, you say I'm a lier. I know what I saw and I know he was at home for at least 2 months. These are facts.
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Peter, the leak you describe happened because you did something for which you were not trained and you did it wrong. Ever hear of hydrostatic trapping? You also were a danger to yourselves and placed yourself in danger and got hurt. Unless you were sweating profusely from your fear in your recent service of ammonia systems, you would not have felt anything on your skin from what you describe you were venting. It was fear you were feeling.
Jesus, you make fast conclusions. Hydro trapping? No never heard of it, we use the Dutch expression for it. :D
Hydro tapping is only possible Mr ammonia if you can vent via a servicevalve to water. And if there is no service valve or the service valve is so rusty that you can't open it anymore. What then wise guy?
You don't know my history at all but make statements. You've become just like Bush.
Your statement about the fact that you don't feel ammonia on your skin, are you a carpenter or so?
I don' t have fear when working on it, I'm just very prudent. That's all.
I will post some pictures from a installation - some of the posters saw them already - we did and you will need to revise your opinion.
Well, why should I post them anyway. Perhaps you should learn from the pictures how you must hydrotrapping. :D
Quote:
Remember, ZERO environmental damage.
And your lungs?
Quote:
Ammonia systems are not inherently dangerous, any more than any other type of refrigerant is. Training and understanding and respect are the key.
The first reasonable quote.
Quote:
...and I have no long term effects because of my training and reactions.
You THINK you haven't them, that's something else.
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TRAINING and DISCIPLINE are the key to safely using it.
I bet a former Marine.
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A water cooled condenser is NOT a complex piece of equipment! You cannot get any simpler than that!
I didn't said it was.
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We in ths USA are not "lucky". The OSHA and EPA regulations class us in the same category as poisonous chemicals where one or two molecules absorbed into the skin will kill. We take great pains to use and design ammonia systems safely. Education and training are the key to the safe use of this refrigerant.
You think that regulations are elsewhere less strict then in Cowboyland??
Come on!!
Why Bush won't sign the Kyoto agreement or at least why won't he follow the proposed limitations?
Quote:
Virtually every system has detectors to start remote response to a leak in any form.
Why you install them anyway? Because it's more danger IF something should happen.
Quote:
Ammonia refrigeration trained personnel are at the top of training and
Waw, glad you say it from yourself. Makes it very believable. All we, the other ***** guys are de facto the stupid ones now.
Quote:
They deserve to make better money. However, in the USA, ammonia systems are actually less expensive to install and to maintain.
I don't believe this.
Quote:
Elsewhere, welllll... have you ever tried to get 2000 pounds of R22 (back in the early 80s) in the middle of nowhere Kenya? Ammonia was readily available!
Didn't met Marc over there. Lucky for you.
Quote:
As long as you folks in this industry promulgate this fear and disinformation you are so content to parrot here, you will be missing one of the chances to utilize one of the best and safest refrigerants.
sure the best but safest???
PS: that logo, is that from sort of Hells Angels Bike club?
You can see - saw it on your (is it anyway yours?) website that you're in fact not long in business. And I mean as a self-employed one.
You're fallen high but you can fall quick much deeper and faster if you threat all your clients like this. Knowing yyour job and running a business is something completely different. It's not because you're a succesfull tech that you will be succesfull doing the same job but then self-employed. You need that little charisma and adapted attitude (which you are missing)
You have to polish your website a little bit because most of the links aren't working.
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Re: ammonia refrigeration
Peter, I was not speaking directly to you in all of my posting. However, it is painfully clear that you have a limited and somewhat fanciful experience when it comes to using or experiencing ammonia as a refrigerant. Fear of it seems to rule your focus.
I would know the ammonia is in the room and would leave. If I was in the room of HCFC gas, I would not know it... Until asphyxsia or a heart attck occurred. Ammonia is not poisonous or otherwise harmful if you get away from it. Nor is it carcinogenic.
If indeed you did see blood as you describe, you do not understand or know what actually happened. Exposure to ammonia inhalation does not cause blood from orifices. It causes pulmonary edema. You misinterpreted the cause of the blood. There had to be another cause. Period.
The fact that you have never heard of hydrostatic trapping proves you were not servicing correctly and speaks volumes towards your abilities. I teach refrigeration professionally, both in the private sector, and have taught at the college level. Maybe you should consider a little more education? Hydrostatic trapping of liquid is the trapping of liquid between two valves when servicing without vapor present. This causes pressures hundreds of times what the normal P-h diagram would indicate.
"What then wise guy"??? I don't really know, as I was not there, but I assure you I would have completed the work differently without getting a "snoot full".
Your hatred of our government leaders shows through. You seem to only wish to cling to, and foist upon us, these insults. It is a pity. You do not know me at all, but wish to use your political views to disparage me.
It is also a fact that you would not feel ammonia vapor on your skin under the circumstances you describe. I have no idea why or what, but ammonia vapor in that concentration is not going to be felt on your skin. You would have suffered pulmonary problems at this level.
I have no lung damage, and have been around ammonia in high concentrations for many years.
The condenser information was from another member in Australia. The fact that you think I said this about you is telling me that you do not read and understand well what is in this thread.
Actually, I was an officer in the US Army. What does that have to do with anything, except to attempt another disparaging comment?
"Cowboyland"??? ...another attempt to disparage me and my country, no doubt. Be an adult and think. I know not of your regulations you deal with in your country, but your assertion that we are not encumbered with such and react to them as such is a load of mule marbles. Grow up! We are professionals here as well.
Bush will not sign the Kyoto Agreement because it is based upon pseudo-science and conjecture. It is bad for the USA and is not fairly applied to all. For your information, we are under tighter control in many facets than the Kyoto Agreement demands. ANyway, that's a dead issue, and good for it!
I cannot figure out what your objection to my statement of the fact that we employ ammonia detectors in our facilities? This is a rational design requirement to provide the safest system possible to protect life, property and limb.
I never disparaged the ***** guys. That is you. I only said that good ammonia refrigeration tech are at the top of the training and ability "heap". The level of required training is much higher in the USA than for a "*****" residential or commercial technician. A good ammonia tech can virtually be working anywhere, at a higher than average wage. Simple facts.
I care not a whit about what you believe or theorize. I'm stating that an ammonia system for an industrial application such as a winery, cold storage, hog or beef kill facility, etc..... ammonia is a less expensive system to install and maintain. In the USA, anyway.
non-sequitur.... Ammonia is available anywhere in the world. Odd CFC, HCFC, and other refrigerants are not. (Certainly not the odd azeotropes and patented ones.) I guess you have no experience in this?
There have been more deaths in the USA due to non-ammonia refrigerants than there have been caused by ammonia refrigerants. That is fact.
That "logo" you describe is a patch I sell and give to my clients. It is used to identify in an eye-catching way the persons who are trained at a higher level to respond to an ammonia incident. It is a team builder id for use on the uniform and jackets. It is well thought of and I have hundreds of requests for them monthly. (Much better than a pen to give a client too.)
Again you attempt to disparage me and my experience. I have been an owner, Chief Engineer or Senior Engineer of several ammonia refrigeration contracting and enginnering firms and businesses over the years, not just my current one. (I started as a stock boy and welder's helper.) I have served at the national level for our professional organizations. I am known, and a recognized leader in our industry here in the USA. You are clueless as to my business. (Yes, my website does need a refresh, however, it does not really pay the bills directly, and I am much too busy to do so right now.)
You find me abrasive, largely because of your hatred of all that is "cowboy". I pull no punches and speak plainly and truthfully. I owe you nothing but my knowledge and experience to help the industry better itself and possibly help an ammonia techinician to not hurt himself or others and to work safely.
In short, yes, when used properly, there is no better, nor safer, refrigerant to use than ammonia!
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Re: ammonia refrigeration
Now Adolf, there you go again picking on America's Hero
Don't forget Blair is in bed with him, or do you dislike daddy also and who's WE is that all of you :D
OH, and Mark watch out for the idiot previous to my post
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Re: ammonia refrigeration
Quote:
Originally Posted by Marc O'Brien
Perhaps because of Bush and his profoundly well demonstrated "Texan Idiot" characteristics we have all become a little prejudiced in our views of Americans.
:)
Funny, My family has known the Bush family through business contact for years. It's really odd how you "Eurocentric Bush bashers" ... nee "Haters".... have swallowed that press-induced "Dumb Bush" thing hook, line, and sinker. Really, I thought you folks were brighter than that! I teach my kids to examine what they are told and not just believe everything.... :eek: (Psst.... Bush ain't really a "Texan".)
Gee, I'll even bet you think that President Ford was a bumbling pratfall waiting to happen, or that Dan Quayle was stupid too!?? EH? :rolleyes: If you would take the time to examine first hand, instead of parroting the same old political clap-trap, I might believe you were anything more than a.... well, I digress. :D
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Re: ammonia refrigeration
HIP HIP Hurrah, HIP HIP Hurrah, Well said Dear Yank!! :D
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Re: ammonia refrigeration
Quote:
Originally Posted by Marc O'Brien
Gosh, a little confrontation happening here. Nice one :)
Perhaps because of Bush and his profoundly well demonstrated "Texan Idiot" characteristics we have all become a little prejudiced in our views of Americans.
You know, it's funny, we don't blame zimbabweans for Mugabe and we don't blam Iraqi's for Sadam but we blame the Germans for Hitler and the Americans for Bush... funny world :)
This got me thinking. Consider Hilter. To successfully fight him, we had to believe that all 50 million germans were nazi goons, baby bayoneting hun. The fact that most were peace loving normal people tricked into war was ignored. The fact that Hilter dressed SS troops in Polish uniforms and "invaded" Germany on Sep 1, 1939, starting WW2 shows how he had to manipulate his population.
In these politically correct times, you cannot use the "nigger" word unless you are black. You can't criticise Israel unless you are jewish, and you can't point out Bush's lies and deceits without being considered anti-american. This is a pity, since many people confuse the issues and take offense when none was meant.
I have been accused of racism because I think that changing the name of Bombay is stupid. This doesn't bother me, but the accuser now sees more "racist enemies" surrounding him.
We need less anger in the world. Unfortunately, some influential people see it to their advantage to encourage this.
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Re: ammonia refrigeration
Quote:
Originally Posted by baker
....and you can't point out Bush's lies and deceits....
If you can prove any of this, the world wants to know!!! Please do tell, and let's not just parrot that crap you hear on the news that is unsubstantiated and wishful thinking on the part of those opposed.
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Re: ammonia refrigeration
Quote:
Originally Posted by Marc O'Brien
However, observing the American way of thinking has become quite a horror show. In these parts Americans used to be referred to as merely loud clumbsy thinking people, now they're referred to as stupid people. It's "stupid americans" these days, not "americans" anymore and the locals in these parts don't even realise they're saying it...lol.
Not even poor old push, he's trapped himself into that "Texan Idiot" roll for the rest of his life. Listen to his explainations, despite failing misserably at everything he's tried to do, he always has to explain that, despite reality, "he still believes in his heart that he's doing the right thing"... But to people in these parts it's no mystery why he is only ever thinking with his heart. :)
Actually, Marc....
In these parts, Europeans for the most part, including most of Britain, are viewed as being the same old appeasing boobs, completely unable to do anything that needs done. More and more shrill words to condemn, yet nothing is actually accomplished! ....Especially if it is not in their backyard. Where is Winston when your country needs him? OH, Tony Blair stands up to be counted! Europe is business as usual. Appeasement, and inaction. Where did it get you before?
I do listen to what Bush says; He speaks plainly and from the heart. I wonder if, Marc, you actually watched the entirety of what Bush says, or just the edited sound bites the press wishes to show to massage your views? Your press, it is my conclusion, manipulates your opinion through what they choose to show, and most Europeans, and Britons, do not get the entire truth. Like I said, don't live an unexamained life; Why don't you think for yourself?
Once again, this forum, despite being a "Refrigeration" forum, is jaded by the blinders of your politics. Your views come out, I can only assume, to disparage me. Let's get back to the subject!
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Re: ammonia refrigeration
Quote:
Originally Posted by chemi-cool
hi andy,
dont ammonia attacks aluminium?
chemi
Yes, and no. Certain Aluminum Alloys are more prone to corrosion than others, but mostly it is a function of the fabrication properties of that alloy which determines what one is used. Aluminum tubes are frequently used for Ammonia systems. Care must be taken of course to use dielectric couplings where transitioning to a steel piping system.
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Re: ammonia refrigeration
Quote:
Originally Posted by Mark C
More and more shrill words to condemn, yet nothing is actually accomplished! ....
What has the US lost in Afghanistan? Only the fact that you need the country to install a huge oil -pipeline from Turkmenistan to Pakistan. The other route was via Russia which they didn't of course not preferred.
Don't forget also that they created there Bin Laden, they funded him with billions of dollars. Or was this not in your news?
What have they lost in Iraq now? Mass destructions weapons? The troupes didn't found any Gas weapons? Nuclear weapons? Zero decimal zero?
The only thing they wanted was a complete control of the oil.
The reasons why they attacked Iraq were seen afterwards all been false.
That's what Richard Clarke, anti-terror expert since 30 years 'Against all enemies' also said 2 weeks ago in his new book (was it in your bookstores or Bush bought them all at once?)
The whole state was shaking man.
Clarke know his job I think, otherwise they shouldn't let him there for so many yeras.
Exact same story for Kuwait? Such a small country. Why didn't they interfered in Rwanda where hundred thousands were killed, why they didn' t helped in the Sahel... One simple answer.
What have they lost in Israel?
Quote:
I wonder if, Marc, you actually watched the entirety of what Bush says, or just the edited sound bites the press wishes to show to massage your views?
The speeches he gives is what other has written for him. Those who fund him, he's only a puppet on a string and has to do what his fund raisers advise him (if he wants to be elected in June)
Quote:
Your press, it is my conclusion, manipulates your opinion through what they choose to show, and most Europeans, and Britons, do not get the entire truth. Like I said, don't live an unexamined life
It's the world upside down, you don't have a clue what we ares seeing here and what they tell us here. That's clear now.
It's your media which is so hypocrite. They beep the words f**k and s**t and some other obscene ( are they anyway?) out in every ting on the television but on the same time when they say f**k, they shoot somebody or put a knife in someone's stomach, completely unsecured and if they let show a breast, they fade it out. (what a pity) What's the logic in this.
What will frighten a kid more? Do you think kid never saw a breast before? It was the first he saw when he was born.
We dare to say for what we stand for, even if it's not the opinion of the US. And sometimes with great consequences. Look what happened with the Iraq crisis in Belgium. Belgium refused to cooperate without a UN resolution which was fair.
And that's why they have installed the UN: to prevent peoples like Bush doing stupid things in the world. Beut he was so egocentric when he said "well, i will attack, even without a UN approval"
He thinks he is God himself.
What was Bush' reaction to this: we will move the NATO headquarters in Brussels. Bush forgot that NATO not stands for US, he thinks that this building is a US building.
Thats the reaction of a child. I you don't do what I' saying, then I will take your candy.
I didn't turned my head when Janet Jackson showed her breast. And in the US it was big news, it even overwhelmed the Iraq news.
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Re: ammonia refrigeration
Quote:
Originally Posted by Peter_1
What has the US lost in Afghanistan? ....
Hey Peter, you Euro-boob. Get back to the topic at hand... Refrigerants, specifically in this thread ammonia. I tire of your diatribe of stupidity and blathering.
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Re: ammonia refrigeration
Quote:
Originally Posted by Marc O'Brien
Hey, Peter, did I tell you what they call Americans around here these days? Lol, seems I did :)
Oh, Marc?? If you cannot keep topics "on topic", in a professional refrigeration fourm, and cannot resist delving into that trashing of members and participating in such.... Well, you are not much of a "Moderator".
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Re: ammonia refrigeration
Hi :)
we Irish are slowly learning to keep our politics to ourselves, it has been a painfull slow lesson played with peoples lives :(
I suggest you guys keep your politics to yourselves, for fear you end up like we did in the North of Ireland :(
On a lighter note why do we even bother using ***** :D Ahh now I remember so we can charge the customer for endless hours leak testing :D :D
Kind Regards. Andy. :)
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Re: ammonia refrigeration
Quote:
Originally Posted by Andy
"....On a lighter note why do we even bother using ***** :D
Hold that thought!! I like that idea.... http://www.mboxcommunity.com/images/Jester.gif
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Re: ammonia refrigeration
I wonder how much of ammonia's success is due to it not being miscible with oil. Lack of oil in the evaporator must surely make it more efficient.
It has been reported that R410A is inferior to R22 theoretically (thermodynamic calculations) but better in practice. With oilless compressors now becoming available, it will be interesting to see if they are ever used with NH3.
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Re: ammonia refrigeration
Friends,
if this is the way we are going to correspond to each other than I am
out of this conversation. I think we have an ethical Code of Conduct
to behave on this Forum
jg/oz
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Re: ammonia refrigeration
In scientific circles, there is a testing procedure known as "double-blind testing" in which neither the test subjects nor the professionally-trained observer knows which subject received the real drug and which received an inert compound.
It has been discovered that this procedure is essential because even a professionally-trained observer trying only to be unbiased is unable to do so if he knows which drug is real. His beliefs about the test affect his observations.
Since our biases affect our very observations themselves, how can we possibly hope to know the truth if we can only perceive what we already believe to be true? We can't. We tend to accept evidence that supports our beliefs and discount evidence that does not.
Moreover we identify with our beliefs and feel that anyone attacking those is attacking us personally.
The scientist recognizes that everything rests on assumptions, fallible observations and fallible processes. So to think rationally means we must doubt our own conclusions and seek the errors in our own thinking all the time.
The opposite of this is certainty. This is the hallmark of those who have closed their minds. If you are certain you are right, you are not operating in the domain of rational thought but in that of emotional "rationalizing" thought. This is natural because our experience is more powerful than our thinking. If you experience a feeling, the rationalizing brain has the relatively simple task of rationalizing the feeling rather than reasoning towards the truth. Evidence which contradicts the feeling can be ignored since it is obviously in error.
So the first clue that you are not really thinking is that you have a strong feeling about the subject. The second clue is that you are convinced you are right. The third clue is that your thinking is simplified: you think in categories (liberal vs conservatives, evil vs. good), generalizations (those people are all jerks, inferior), and other simplifications. The fourth clue is that you don't refute ideas, you attack the holder of the idea (ad hominem attacks).
My own technique for trying to approach the truth is to assume that human nature is pretty much the same everywhere. Self interest tends to bias perception for everyone about the same. I think most people are sincere in believing what they are about is in the best interests of humanity.
The men who piloted the airliners into the World Trade Center believed they were doing God's work and striking a blow against Satan. The men who called for a bunker-busting bomb to be dropped on a residential Baghdad neighborhood because they thought Sadaam was there believed they were waging a war against "evildoers" and the loss of innocent lives would prevent larger losses later.
I suspect what we are seeing is a stage in the evolution of humankind. We have evolved to a point where we are altering our entire environment by using our rational minds, but we have not yet learned to act rationally. Will we make it?
Rog
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Re: ammonia refrigeration
jg/oz :)
don,t take these guys seriously, they are all piss and wind :D I don't think any of them are entirely serious about the political ideals they are coming out with.
I know for a fact that Marc is taking part in a little known past time called Yank bating, which to date has been quite sucessful. :D
I fear our friends accross the Atlantic take critisim from europeans much too much to heart. If the same debate was to go on between two europeans, the needling would not be taking anyway near as seriously. ;)
Kind Regards. Andy :)
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Re: ammonia refrigeration
Quote:
Originally Posted by Marc O'Brien
Says who?
Says, me, you twit. "Pouncing" ... "tearing apart"??? Get a life and get real. You came to a battle of wits unarmed. You are not much of a moderator in a professional forum in which you take part in this O/T baiting game. You are a "Euro-boob" yourself.
GET BACK ON TOPIC, or go elsewhere. This is the absolute last time I will respond to anything you ever say that is not refrigeration related. You are a failure.... GOODBYE!
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Re: ammonia refrigeration
Quote:
Originally Posted by baker
I wonder how much of ammonia's success is due to it not being miscible with oil. Lack of oil in the evaporator must surely make it more efficient.
It has been reported that R410A is inferior to R22 theoretically (thermodynamic calculations) but better in practice. With oilless compressors now becoming available, it will be interesting to see if they are ever used with NH3.
Oil management is indeed quite different with ammonia. It does require a different mindset. I sure would not say that there is a complete lack of oil in the evaporators and throughout the system! The immisicibility of oil in ammonia is one of its attributes!
It is quite possible to completely log an avaporator with oil, and, like all oil in a refrigeration system, it acts like an insulator. It is not an uncommon experience for me to have shown up on a service call that a room will not cool to find an oil-logged evap! Usually, this is at a time when the hot gas has not kept pressure high enough to blow the oil through on defrost. (As in winter or other low ambient conditions) Sometimes, it is just an accident of piping or valving (disrepair) that allows this to happen.
Make no mistake, oil needs to be managed in the ammonia system.... It needs to be recognized that it settles in and needs to be removed!! :D I have one client who lets it accumulate for the entire grape cooling season in California. When all the grapes are shipped after that season, it is their time to drain oil.... hundreds of gallons of it! Per coil. Mind you, these are huge pressure cooling systems that have huge coils in a bunker-coil setup.
I have not played with the newer replacement "*****s" to have any opinion on them. However, I do not believe that any design consideration will call for the ammonia industry to attempt the use of "oil free" compressors. It just is not a big deal to go drain oil once in a while!
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Re: ammonia refrigeration
Quote:
Originally Posted by RogGoetsch
In scientific circles, there is a testing procedure....
Rog
<<<Scratching head>>> Ever the diplomat, Roger! (All while holding a club that the other fails to notice.) You never change, and I like that! :D Rog and I went to the same school, and have worked at the same company.... we go "way back".
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Re: ammonia refrigeration
Gentlemen.
I do believe you have went "off Topic"
Please return to topic, thanks
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Re: ammonia refrigeration
hi mark,
dont you use oil separators in ammonia based systems?
chemi :confused:
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Re: ammonia refrigeration
Quote:
Originally Posted by chemi-cool
hi mark,
dont you use oil separators in ammonia based systems?
chemi :confused:
Yes, chemi... These are typically coalescing filter elements that are installed post compression. (It is rare today to use a central vessel to do this.) However, these are not 100% effective, and They pass about .05% of the oil anyway if they are in good condition. So the oil circulates freely in the system and winds up in the low spots, which are typically at the bottom of liquid recircualtors, and Oil distallation Pots are used to remove it from the system.
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Re: ammonia refrigeration
hi mark,
the reason I asked is that some years ago I was asked to look at a condensing unit ( a miniture in your respect) 20 HP that was feading 100% fresh air 25 meters below and the oil presure controls triped every week.
the tech that was looking after it said he had added some 40L per month!!!!!
of oil.
there was no oil separator used!! strange design.
left them an offer to fix the unit and after two weeks they called back- now it is not cooling either!
what I did was recover all the gas, install an oil separator and.... at the bottom of the evaporator brazed 3/8 tube and an SV controlled by compressor's contactor that opened for 30 sec 5 min. after unit came on.
the end of this tube went int the suction line just before the condensing unit.
because of the presure dif. it pushed the oil that left inside the evaporator up.
after recovering the system, 45L of oil came out!
chemi
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Re: ammonia refrigeration
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Re: ammonia refrigeration
so why not use it in ammonia systems?
chemi
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Re: ammonia refrigeration
Quote:
Originally Posted by chemi-cool
so why not use it in ammonia systems?
chemi
I guess the best response would be that it just doesn't matter all that much. The oil in an ammonia system gets trapped mostly in the oil coalescing filters at the compressor oil seperator. The small amount that gets by that gets trapped in the oil distallation pots. The small amount that gets past both of those generally gets blown about until it settles back into the oil pots.... We simply drain it when it is there.
Only on the oldest of systems where there is no coalescing oil filter at the oil seperators do we see quite a bit of oil to be distilled. It's just a part of the normal "things to do".
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Re: ammonia refrigeration
Hi chemi :)
on our low pressure receiver systems, we would automatically drain the oil from the receiver, PAO oil is used in these systems. Doesn't really matter about a little carry over as it all makes it way back to the LPR and is rectified.
Mark/Chemi :)
before you ask an LPR system is a liquid over feed system, with usually one or two coolers on it. Liquid is fed into the evaporators by an expansion device, much like DX, the liquid comes out the cooler suction line and is trapped in the LPR and boiled off by indirect heat exchange using the haet available from the liquid off the condenser, subcooling the liquid in the process.
Nominal capacities are 100 to 400kW at -30 C evaporation.
Kind Regards. Andy :)
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Re: ammonia refrigeration
Quote:
Originally Posted by Marc O'Brien
Lol, what's there to arm myself for?
Back to the subject at hand.
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Re: ammonia refrigeration
Quote:
Originally Posted by Andy
Hi chemi :)
on our low pressure receiver systems, we would automatically drain the oil from the receiver, PAO oil is used in these systems. Doesn't really matter about a little carry over as it all makes it way back to the LPR and is rectified.
Mark/Chemi :)
before you ask an LPR system is a liquid over feed system, with usually one or two coolers on it. Liquid is fed into the evaporators by an expansion device, much like DX, the liquid comes out the cooler suction line and is trapped in the LPR and boiled off by indirect heat exchange using the haet available from the liquid off the condenser, subcooling the liquid in the process.
Nominal capacities are 100 to 400kW at -30 C evaporation.
Kind Regards. Andy :)
Ummmmm, not really.... I'm well aware of the nomenclature of the ammonia system. However, these systems sometimes have sixty or more evaporators, ice makers and other heat exchangers on them. I would not limit them to "one or two coolers on it." I have designed, installed, and operated systems with 9,800 connected BHP operating at multiple temperature levels down to minus 60°F.
Liquid is fed to the evaporators through a hand expansion valve which is actually used as a balancing valve. The actual expansion to low temperature happens within the recirculator vessel, and not at the evaporator.
when heat is added at the evaporator, the liquid present then flashes to vapor, absorbing the heat. There is no DX evaporation, and certain not any superheat generated. There is no TXV or superheat to be "set" here, and two to five times the vapor weight (depending on temperatures and the needs of the circuiting) is returned to the recirculator vessel via gravity after exiting the evaporator and riser.
The returned liquid is then pumped out or "recirculated" to the evaporators again. The oil, usually heavier than the refrigerant liquid is traped in the recirculator vessel. What small amount does get out to the evaporators is returned with the liquid ammonia returning from the evaporators after a high load "blows it through the coil" or the coil is defrosted, and drained of all liquid.
Oh, and there is nothing "unreliable at best" regarding a properly designed and circuited ammonia refigeration system. As a matter of fact, there is nothing more reliable or efficient! Anybody that uses a TXV on an ammonia system really does not understand the proper design and use of an ammonia system. TXV should rarely be employed on an ammonia system.
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Re: ammonia refrigeration
Hi Mark :)
LPR systems may have only a few coolers on them, but they are not DX in nature but liquid overfeed. Charges are critical, and thus an LPR system allows Nh3 to be used where it would normally not be aceptable.
Pumped Nh3 has it's place, but that would not be on the roof of a building in London. LPR chillers are now quite common on government building in London.
The only DX Nh3 we use is for economisers on plate and shell heat exchangers :)
Kind Regards. Andy :)
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Re: ammonia refrigeration
Quote:
Originally Posted by Marc O'Brien
Andy, surely the most widely seen application of ammonia is in the form of liquid overfeed, LPR or PLA, because overfeed assists oil return
I would say so. I did see a good aplication of DX Nh3 once. A compound compressor plant had an extra high stage compressor, to handle the a high temp side load at intermediate pressure. The rooms requiring high temp cooling were fed H.P liquid by DX valves and the subsequent dry return was fed into the interstage closed flash intercooler. :D
But that is the only one in 15 years ;)
So DX Nh3 is not common.
Kind Regards. Andy.
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Re: ammonia refrigeration
Hi Mark :)
yep a loading bay also. Neat solution where only a small to medium sized HT load is required.
Kind Regards. Andy :)
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Re: ammonia refrigeration
When I joined this forum It was with the express purpose of trying to help others in our industry with my 40+ years of experience, but it didn't take long to get bashed buy adolf and a few others with your chicken **** politics. Some of you have a real problem understanding us "Colonials" .
Admin note
this poster goes on to express his opinion in a rather forceful way.
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Re: ammonia refrigeration
OK, I gave you all a chance to get back to the subject.