Cyro reefers?

[Lyon_Wonder]

I also posted a similar message in the model railroad "prototype" forum too.

In the 1990s a fleet of reefers emerged that used cryo-CO2 to cool it’s perishable loads instead of mechanical refrigeration.  A company called Cryotrains operated these 70' reefers.

http://www.railcarphotos.com/PhotoDetails.php?PhotoID=5516

Were cyro-reefers the modern reintroduction of the ice reefer?  Of course it looks like Cyrotrains reefers have been converted to mechanical refrigeration judging by the outside refrigeration unit in recent photos of these cars. 

http://www.railcarphotos.com/PhotoDetails.php?PhotoID=31789

ARMN and other current reefer fleets are mechanical too, so it sounds like cryo-refrigeration didn't catch on very well.

[j610]

I saw a couple of white boxcars with cryo on them pass through roanoke on the norfolk southern a few weeks ago . I didn`t notice if they had been converted to regular reefers .   RON

[PNWRMNM]

Lyon.

Cryo trans cars use liquid carbon dioxide (CO2) as their refrigerant.  I worked for a short line that regularly originated them.  While I never got the grand tour, I was told that they had a trough under the roof in the load space that was full of CO2 "snow" while in transit.  The snow was solid CO2 which as it converted from solid to vapor pulled heat out ot the car.

Creating the snow also pulled heat out of the car.  I suspect that there was/is a pipe with either small holes or nozzles that runs along either the top or bottom of the trough.  Liquid CO2 is introduced from a truck or storage tank, goes through the pipe, is discharged and flashes to both vapor and snow chilling the car to well below zero.  The snow sublimes for the rest of the trip, maintaining the cold temperature,

If you have ever discharged a CO2 fire extinguisher you have seen all this happen.  The discharge is liquid which flashes to vapor and "snow" at ambient temperatures.

These cars are NOT suitable for anything other than frozen which is why you still see mechanicals.  They are much less complex than mechanicals.  The only thing that would render them noncompetitive is if liquid CO2 got too expensive.  I do not track CO2 prices. 

Mac McCulloch

[PNWRMNM]

Lyon,

I looked at your pix after doing my first response.  Note that the mechanical has a higher number than the cryo car.  I suspect that the company has simply expanded to leasing mechanical cars IN ADDITION to the cryo cars.

That is a corporate line extension, not an indication of failure of the cryo cars.

Mac

 

[Paul_D_North_Jr]

Two non-expert comments:

1.  Cryogenic cars are kind of a glorified or giant Thermos bottle or picnic cooler, with the advantage of an 'ice block' to help keep them cool - unlike a mechanical reefer, which is kind of like a giant refrigerator or chest freezer on railroad wheels.  

2.  I believe liquid CO2 is a product or byproduct of liquifying common 'air' to obtain liquid nitrogen and/ or oxygen - and maybe other constituents, so depending on who's doing it and why and paying for it, the liquid C02 may be readily available at reasonable cost.  Then again, maybe not:

From the "About MHW - Rail" webpage at - http://www.mhwgroup.com/index.php/about-mhw   [emphasis added - PDN] 

RAIL TRANSPORTATION

Cryo-Trans, Inc. (CTI) secured a patent in 1986 for a cryogenic railcar which revolutionized the frozen rail industry. Between 1986 and 1995, CTI developed long term leases for approximately 500 of these cars. In 2000 and 2001, due to an inordinate increase in the price of CO2, CTI converted the majority of its fleet to mechanical refrigeration.

CTI is currently constructing 75 new 72 foot interior mechanically refrigerated railcars, which will bring its total fleet size in excess of 925 railcars.  Each railcar is equipped with state-of-the-art two way GPS systems. All cars are leased to major food processing companies.

- Paul North. 

[CShaveRR]

I think the MHW web information is slightly dated, Paul.  The name is still Cryo-Trans, but their fleet has been 100-percent mechanically cooled for years now.  Not even a museum piece left, as far as I know.

There were other fleets of cryogenically-cooled reefers at one time (the J. R. Simplot cars come to mind), but I don't know what's happened to all of them (the newer JRSX cars, built as reefers, series 6000-6050 and 6100-6149, are still mostly in service, minus a few retirees; but the older 5000-series cars, rebuilt from SSW box cars, have been retired due to the age of the original equipment--from their Car Type Code, they haven't been rebuilt into mechanically-cooled cars).

[samfp1943]

While looking around, I found the following link : Admittedly it is dated (1996) but interesting.(?)  It has to do with the creation of CO2 "Snow" for shipping frozen foods into tropical areas.

http://www.allbusiness.com/operations/shipping-trucking/554450-1.html

   The use of "Blanketing" of various products cam into Transportation in the 1970's. Nitrogen Blankets were used by companies that transported very temperature sensitive items (ie. Human Blood, for one).

  Ice Cream is another extremely temperature sensitive product that would require very low temperature containment while in transport and storage. It would require a low temp maintaining  blanket;. Nitrogen evacuates all oxygen in the container, and carbon dioxide provides a similar environment.

  Trailer reefer units for those products require high maintenance to provide the low temperature environments for the products they carry. When no longer able or cost effective they are don rated to less temperature sensitive duties.

More and more of the railroad refrigerated cars are utilizing systems mounted on one end of the car and their original use originated in the OTR Trucking industry.

 

[ericsp]

The carbon dioxide has no means to remove heat from the car. The heat from the load and infiltrated heat is transferred to the carbon dioxide. Assuming the ambient temperature is above the temperature inside of the car (which it will probably be), there will actually be more heat inside of the car at the end of its trip than at the beginning.

Cryo-Trans does have some up-to-date information on its website (http://www.mhwgroup.com/index.php/services/rail/fleet-specifications). I suspect CRYX 1200 is still around.

Carl, do you know if the FURX and XTRX cars that appeared to be RCs are still around?

[CShaveRR]

Roger on CRYX 1200--maybe that's their museum piece!

Most of the FURX cars (690000-690108) are still in existence.  The XTRX cryogenic cars (200-242, rebuilt from WP RBLs) are gone, though.

[railcarguy]

Lamb Weston a division of ConAgra had about two dozen cyro cars at one time. Several years ago they performed thermal imaging of all of the cars and found most of them were poorly insulated. They sold them and the new owners reinsulated the cars and applied mechanical units.