Re: Carbon Dioxide Refrigeration
Hi Buckiesr,
Welcome to the RE forums.
The manager is using some of the most convoluted logic I have heard yet.:o
Get rid of the smelly refrigerant, spend several million dollars, use a different refrigerant and then make that refrigerant stink???
That has got to be one of the strangest arguments I have ever seen.:D
Re: Carbon Dioxide Refrigeration
Once people get ideas in their head they are closed to reason. I think that co2 will indeed be regulated jsut as much as other refrigerants because the real issue is about money, not so much environment. I usually, "it is because someone's brother-in-law needs a job!" (i.e. it is really about money.)
When
Re: Carbon Dioxide Refrigeration
When the industry lowers the use of the other highly regulated refrigerants, then they will go after the others. co2 is a big issue in emmisions and might be in other industries except for the fact that production of biofuels are producing the greatest ammounts of co2, and they are funded by the biggest money holders who also have the most connected lobiest. Laws will be stimed until the lobiests stand down. Not to soon I suppose that would mean. But before long they will go after co2 also.
WM
Re: Carbon Dioxide Refrigeration
Iceman, you are in the US, the plant manager has discounted my observation that nearly all of the knowledge with co2 has been acquired in Europe. He says we now know this is not true and that there is substantual project development in the US. He says they are building tons of new facilities in the US using only co2 systems. Much safer, much cheaper, much more effecient. I know he is being fed a lot of stuff from a company that wants to contract the new quick freezer facility we would like to add to our existing ammonia refrigerated plant. I can't seem to even get anyone to think about how we could design the new freezer in such a way that it would help the existing system and solve some of the existing complications. When we met on this issue the other day the IRR numbers were mostly in the red. the one option that was not in the red was pretty low. how many total co2 plants do you know of in the US currently? I keep telling him it is to stinkin cold for what we need. I just consult, I am not the decision maker. but I will inherit whatever we install.
WM
Re: Carbon Dioxide Refrigeration
Quote:
Originally Posted by
Buckiesr
Iceman, you are in the US, the plant manager has discounted my observation that nearly all of the knowledge with co2 has been acquired in Europe. He says we now know this is not true and that there is substantual project development in the US. He says they are building tons of new facilities in the US using only co2 systems. Much safer, much cheaper, much more effecient. I know he is being fed a lot of stuff from a company that wants to contract the new quick freezer facility we would like to add to our existing ammonia refrigerated plant. I can't seem to even get anyone to think about how we could design the new freezer in such a way that it would help the existing system and solve some of the existing complications. When we met on this issue the other day the IRR numbers were mostly in the red. the one option that was not in the red was pretty low. how many total co2 plants do you know of in the US currently? I keep telling him it is to stinkin cold for what we need. I just consult, I am not the decision maker. but I will inherit whatever we install.
WM
Check out this one companies idea on the "future"
http://www.gartner-refrig.com/whatsnew/index.asp
Re: Carbon Dioxide Refrigeration
Buckiesr,
All of the reasons you are stating from your manager are the typical marketing BS used by everyone who wants to sell against ammonia.
Refrigeration systems are as safe as they are designed, maintained, and operated. The refrigerant is only a small portion of the selection process.
Efficiency is one of those over-used words that people throw out when they want to get someones attention.
My guess is there is not more than several dozen large CO2 systems installed right now. There are some benefits to using this, but I think the best selling point is the use of CO2 reduces the total ammonia charge.
People tend to think this is a good thing if it allows them to get out of a PSM or RMP program. Those are the same people who would not fix or maintain a refrigeration system until it blew up too.
Quote:
Originally Posted by Buckiesr
I can't seem to even get anyone to think about how we could design the new freezer in such a way that it would help the existing system and solve some of the existing complications.
I understand. No one wants to touch the "old" system. They always want to install a new separate system so they do not inherit any of the problems which might creep up with the additional equipment being installed. I think this is just an excuse to not think!
Is IRR who I think it is?:rolleyes:
Re: Carbon Dioxide Refrigeration
IRR = Internal Rate of Return This is one method for calculating the return on an investment. Not the most accurate way in my opinion. It is really easy to make mistakes and arrive at a false return. There can be multiple IRRs for the same input. The ROI (return on investment) is normally used and is how long will it take for the savings on the project to pay for the investment, including taxes, depreciation cost for the firm to borrow the investment money. By comparing what the end result ends up compared to what they are paying their investors, and/ or what they calculate they could make by investing in some other opportunity. (this is called Opportunity Cost). I bet you already knew all of that I wanted to see if I can remember it still.
WM
Re: Carbon Dioxide Refrigeration
Sorry, I didn't mean to turn that into a memory test. You did OK though.;)
It would be interesting to see the actual power input differences between the NH3 and CO2 systems. It can't be too much if the economic costs were in the red.
Re: Carbon Dioxide Refrigeration
Quote:
Originally Posted by
Andy
good job it was R404a not an ammonia job;) now that would be fun:D
Ah, the delightful Ammonia Carbamate :eek:
Don't we have detectors for that?
Re: Carbon Dioxide Refrigeration
Hi, Buckiesr :)
Welcome to RE
Quote:
Originally Posted by
Buckiesr
Our plant manager is terrified of NH3, he says it all has to go. he wants all co2. I surmise that in the long run, more deaths will be attributed to co2 deaths than ammonia. (due to sensory properties.)
So he asked me, can we put smell in it like they do natural gas? I don't have a clue if it can be or is done or if anyone ever tried. I suggested maybe we should try color, then when you see purple haze you vacate.
WM
I am so sorry about you having that type of person for manager;), your life must be very complicated... I must ask is he/she younger or older of you?
.....agree with you about accidents with CO2...for me is normal if lot of people use something (electricity, gas, cars...etc) there should be more accidents relating to that -whatever is...
I assume that you have an old ammonia plant with many problems due to bad design, maintenance, installation, etc (maybe I am wrong), but that is not and must not be a reason to not use ammonia especially in industrial area....
Coming back to CO2....
Quote:
Originally Posted by Buckiesr
...co2 is a big issue in emmisions and might be in other industries except for the fact that production of biofuels are producing the greatest ammounts of co2, and they are funded by the biggest money holders who also have the most connected lobiest....
I've been told the biggest emission of CO2 is when raise rice...but who have the power to stop production of main food for almost 60%+ of Earth population..
Quote:
Originally Posted by Buckiesr
..He says they are building tons of new facilities in the US using only co2 systems. Much safer, much cheaper, much more effecient. I know he is being fed a lot of stuff from a company that wants to contract the new quick freezer facility we would like to add to our existing ammonia refrigerated plant. I can't seem to even get anyone to think about how we could design the new freezer in such a way that it would help the existing system and solve some of the existing complications....
Using only CO2 in primary circuit is possible and then R404 or NH3 in secondary, but to use CO2 only :confused: without cascade I cannot see to much common sense,
Quote:
Originally Posted by US Iceman
All of the reasons you are stating from your manager are the typical marketing BS used by everyone who wants to sell against ammonia.
Refrigeration systems are as safe as they are designed, maintained, and operated. The refrigerant is only a small portion of the selection process.
Efficiency is one of those over-used words that people throw out when they want to get someones attention.
My guess is there is not more than several dozen large CO2 systems installed right now. There are some benefits to using this, but I think the best selling point is the use of CO2 reduces the total ammonia charge.
People tend to think this is a good thing if it allows them to get out of a PSM or RMP program. Those are the same people who would not fix or maintain a refrigeration system until it blew up too.
...US Iceman, sorry, English is not my mother tongue and I found on www. ...marketing BS=marketing bull**** is that right, I believe it is;) from complete sentence and I agree with you...furthermore please can you post some link or send me something about those CO2 plants...thanks.
Quote:
Originally Posted by Buckiesr
IRR = Internal Rate of Return This is one method for calculating the return on an investment. Not the most accurate way in my opinion. It is really easy to make mistakes and arrive at a false return. There can be multiple IRRs for the same input. The ROI (return on investment) is normally used and is how long will it take for the savings on the project to pay for the investment, including taxes, depreciation cost for the firm to borrow the investment money. By comparing what the end result ends up compared to what they are paying their investors, and/ or what they calculate they could make by investing in some other opportunity. (this is called Opportunity Cost). I bet you already knew all of that I wanted to see if I can remember it still.
WM
...profit....bigger profit...the biggest profit whatever it cost. No, I am not against to calculate IRR, ROI, etc...to see what we'll get for money we invest...,
but to install one "safe, cheap, efficient" plant using too much energy to run it, we must burn more fossil fuel and produce much more CO2 and release it in atmosphere, is that logical:confused: - safe, cheap or efficient???
Best regards, Josip :)
Re: Carbon Dioxide Refrigeration
Quote:
Originally Posted by Josip
...marketing BS=marketing bull**** is that right...
Yes sir you are correct.:D
The few adverts I have seen for CO2 systems have not provided very much raw data. I'm sure you realize any numbers provided may be suspect, because someone is trying to sell something.;)
Re: Carbon Dioxide Refrigeration
I am so sorry about you having that type of person for manager;), your life must be very complicated... I must ask is he/she younger or older of you?
.....agree with you about accidents with CO2...for me is normal if lot of people use something (electricity, gas, cars...etc) there should be more accidents relating to that -whatever is...
RE: Josip. I assume that you have an old ammonia plant with many problems due to bad design, maintenance, installation, etc (maybe I am wrong), but that is not and must not be a reason to not use ammonia especially in industrial area....
My system is nearing 50 years old. But We have retrofitted many things to keep it up. I keep fining ways to gain effeciencies. To answer your question. The manager is near my age. I think older but not positive. He has read about bad things with ammonia. He is inherently fearful of it that is all. Ignorance can cause great anxiety in people of great responsability. We have had several deaths in the industry in the US this past several years. His fears are partly due to this. sales people like to play on fear if they detect it. They lead him along but now they are promoting a seald ***** or ammonia system for the new freezer and not co2. The other day one of my co-managers made a comment in a business meeting concerning the Engine Room here. he said that he has seldom ever walked through an engin room for an ammonia system and not been able to detect the slightest smell of ammonia but our is the exception. "that has to testify to our Engineer" I liked that comment. I try to keep the Engin Room as nice as I can, even at 50+ years old.
WM
Re: Carbon Dioxide Refrigeration
Jesip
Quote:
Originally Posted by
US Iceman
Yes sir you are correct.:D
The few adverts I have seen for CO2 systems have not provided very much raw data. I'm sure you realize any numbers provided may be suspect, because someone is trying to sell something.;)
If you can know what the costs will be innitionally, and future costs, as well as the returns, then you can do an IRR. However when your guessing, it is tough. You sell your idea to the investor by showing what the return on his investment will be. it is like saying: If you give me this ammount of money to invest in my project, I will give you a return on that investment of ??% which will get all of your investment back in you hands in this much time, and then you will make all profit after that for the life of the project. Projects have a set ammount of time to depreciate completly out. companies set that time. ours is set for 7 years. My projects need to pay back the investment in 5 years or less to look good. calculating the IRR is the method of showing them how much this project is worth to them. If I set up the figures and add future costs to the project I can show more than one IRR. If you only used money you already have there is no IRR. Every time there is a sign change (putting in money-a cost- that is a minus, when you get money back- that is a plus. if you put in more money, that is what a sign change is; going from taking out to putting in.) I buy a flashlight for 5.00; -5.00, I save .50 on each candle I don't have to buy because I am using the flashlight for light. But after 10 candles worth of light, the batteries run down. Now I have to buy new batteries at 3.00. so -5.00 buy flashlight, +.50X10saved not buying candles, -3.00 new batteries. that is a sign change. Every time you have to add investment money to keep it going the IRR for the project would change. My point was that I can actually arrive at the number I want to show by playing with the numbers. I was saying this is why it is not the best method for calculating the return on an investment. I recomend that the ROI be used to demonstrate the value, present and furture, of a project.
I hope that helps you understand what I was saying.
WM
Re: Carbon Dioxide Refrigeration
I'm sorry if I messed up sight. No posts since my last?
WM
Re: Carbon Dioxide Refrigeration
Incressed the co2 pressure to 40 barg and use the glycol oil cooling system via heat exchanger to incress the temp to get around 20 to 30 deg C and we defrost the coolers.
Re: Carbon Dioxide Refrigeration
I want to design a small co2 cooling system and I don t know how to start, I need to select all the equipement.
Can some help me !
Re: Carbon Dioxide Refrigeration
what is the application? evap temp? capacity in kw?
Re: Carbon Dioxide Refrigeration
Quote:
Originally Posted by
Andy
Hi Bruce:)
AndyP's company use a hot gas generator. Liquid is taken off the R744 condenser, fed to a pump which raises it's pressure to about 10 deg c saturation. The liquid is then boiled oil using waste compressor heat and the subsequent hot gas is used for defrosting the evaporators.
Hope this helps. Kind Regards Andy:)
Let me revamp and resurrect this thread.
I don't understand the principle of operation of this defrost.
In a R717/R744 cascade system, in order to defros CO2 evaporator, NH3 is taken off the condenser and then what?
Re: Carbon Dioxide Refrigeration
Andy, I have some questions, because a customer said in USA existing plant for precool with CO2 or N2 the fruit that enter to the IQF. You have some experience with that??.
Re: Carbon Dioxide Refrigeration
Sorry to interrupt your technical discussion, but this is absolutely worth to be mentioned here: Have you seen the major announcement by the Coca-Cola CEO, that Coke will use 100,000 CO2 beverage coolers by 2010? He said, CO2 is safe, reliable, and more efficient than HFC. I am not allowed to post direct URLs yet but the story is quite good: r744.com/article.view.php?Id=666&latest=1
Sounds like a real commitment this time... Let's see if others get moving soon.
Re: Carbon Dioxide Refrigeration
Quote:
Originally Posted by
NoNickName
Let me revamp and resurrect this thread.
I don't understand the principle of operation of this defrost.
In a R717/R744 cascade system, in order to defros CO2 evaporator, NH3 is taken off the condenser and then what?
You've missed a small detail in Andy's post - no mention was made about using NH3 (R717)
liquid R744 (CO2) is taken from the condenser - actually its from the HP reciever - then boosted in pressure and fed into the defrost hot gas generator, where heat from the high stage oil coolers is used to superheat the liquid into hot gas suitable for defrost.
Star have this system patented so perhaps if you need more info contact them or Andy P.
Re: Carbon Dioxide Refrigeration
hi guys, newbie here in the forum!
right now, i need to design a CO2-NH3 cascade system. i already have some major components selected already (compressor, aircooler, condenser), but i have no idea on how to select the pipe size, vessel and valves for the co2 side. is there any table / guide i can use?
hope you could me out on this one. thanks!!