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How much heat energy does LN2 contain per lb.?

I would like to know how much heat energy liquid nitrogen contains per lb. In other words, per lb. of liquid, how many BTUs of heat would N2 absorb in the process of coming up to about 60F? I want to capture the cold energy of nitrogen as it vaporizes...

Refilling process of a helium cryogenic plant

I’m trying to collect some information about the refilling process of a helium cryogenic plant. Due to the physiologic losses I expect to have to foreseen a periodic refilling of helium. Our plant will be characterized by a refrigerator/liquefactor. A control cryostat with 4.5 K LHe coming from the liquefactor...

What's the best gas to use for pulse GMAW?

I have a 78″ ID vessel, 3/8″ thick shells, ½” heads, from SA-240-304L, which will have an ASME U-Stamp and I am planning on sub-arcing the seams and using pulse GMAW (ER308L for both) for the nozzles. I am comfortable with the SAW, but I am wondering about the best...

Manufacturer of liquid pump for use at 170 K

We’re in need of a liquid pump for use at 170 K in our refrigerator to pump Paratherm cryogenic heat transfer fluid. Can anyone suggest a manufacturer? Our flow rate is 16 liters/minute, and a head of 10 m. The specific gravity of the fluid is 0.85 and the viscosity...

Question about configuration of an 80 K helium circuit

I have a question about a possible configuration of an 80 K helium circuit from our cryogenic plant. A helium flow at 80 K and 18 bar is needed at the customer’s inlet. In order to decouple the refrigerator from the customer, I thought to propose the following solution: –...

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Helium-3

Helium-3 (3He) is one of the two stable isotopes of helium. The other is the much more common Helium-4 (4He). Neither of these isotopes should be confused with He II, which is the second liquid phase of 4He. He II was discussed in this column in the Spring 2010 edition...

Cryopumping

Cryopumping refers to the use of cryogenic temperatures to produce vacuum in enclosed spaces. More broadly, it can also refer to the removal of gases via cryogenic temperatures from a flow stream or enclosure without necessarily resulting in vacuum pressures. This is an important application of cryogenics and is used...

Thermal Acoustic Oscillations

Thermal Acoustic Oscillations (TAO) are a common event in cryogenic systems that can have significant adverse effects on the performance of the system. TAOs are sustained pressure oscillations that can occur in tubes containing gas, closed at one end (the warm end) that have a very large temperature gradient along...

Air Separation and Liquefaction

by Nils Tellier, PE, President, EPSIM Corporation (CSA CSM) nils@epsim.us All illustrations courtesy EPSIM Corporation Background History of Air Separation and Liquefaction This section builds on a rich history of methods to develop deep refrigeration and cryogenic liquefaction during the 19th Century. You are encouraged to read Cryo Central’s History...

Bose-Einstein Condensate

A Bose-Einstein condensate, first proposed in 1925 by Albert Einstein based on work done by Satyendra Nath Bose (the same Bose from whom the term boson is derived), is a super-cold state of matter in which almost all of the individual atoms have “condensed” down to the lowest possible quantum...

Cold Technology for Pest Control

While it does not reach temperatures cold enough to be called cryogenic, carbon dioxide snow is at the heart of a new way of dealing with unwanted pests. It utilizes a quick freezing process that takes advantage of the properties of carbon dioxide snow and has a number of benefits...

Cryogenic Finishing

The following 3 articles discuss the uses and procedures of various type of cryogenic finishing. 1) By Robin A. Rhodes, Cryogenic Institute of New England, Inc. rrhodes@nitrofreeze.com Cryogenic Deflashing is employed to remove undesired residual mold flash that remains on molded parts after they are removed or ejected from the...

Need help with temperature dependent model

I am a fourth-year student at New Zealand University. My name is Xu Ke. I have a project to generate a temperature dependent model for inductor, capacitor and diode by using PLECS. PLECS is software which acts as a toolbox for MATLAB. In my models, the temperature is very low,...

In what form is water available in LN2?

Does anybody know in what form water is available in LN2? There probably is a block of ice in the bottom of the tank. But as water comes in many shapes, I can imagine snow or crystals floating free in the LN2. When water is available in LN2, could small...

Separating gases using cryogenics

We are looking for some consulting engineers who understand how to separate gases using cryogenics. We have a new process which takes biomass and converts it to 5 gases and we need to separate these gases into their pure forms. Thanks for your help. Malcolm Draper Energy Research Group LLC...