Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
 Pages:  1  2
Author: Subject: Liquid Nitrogen Dewars. Why so expensive?
tommy claisen
Harmless
*




Posts: 14
Registered: 27-9-2015
Member Is Offline

Mood: No Mood

[*] posted on 3-12-2015 at 15:42


We used to keep our microbial stocks in vials in racks which were suspended in a big ass dewar. It only had to be topped off like 4 times/year... Don't have to worry about the power going out, unlike the -80 freezer we got to replace it.

Although I don't miss the times the lab manager would pipette a little ln2 into an epi and sling it under the door into the lab where I was working! Bastard.
View user's profile View All Posts By User
Deathunter88
National Hazard
****




Posts: 519
Registered: 20-2-2015
Location: Beijing, China
Member Is Offline

Mood: No Mood

[*] posted on 3-12-2015 at 16:20


I agree with what is being said previously on this thread, I don't actually own a dewar but I spent a lot of time looking at buying one and so I learned that high quality ones can hold liquid nitrogen for surprisingly long times. There are two types of dewars, those for storing liquid nitrogen, and those that are used for transporting it from the storage dewar to the lab. A 10L storage dewar can hold liquid nitrogen for over 150 days, while a 10L transport dewar can hold the same amount for only 4-5 days. Thus for amateur science the storage dewars are the way to go. The 20L ones can hold liquid nitrogen for over a year I think.
View user's profile View All Posts By User
Dr.Bob
International Hazard
*****




Posts: 2736
Registered: 26-1-2011
Location: USA - NC
Member Is Offline

Mood: No Mood

[*] posted on 5-12-2015 at 06:31


I have heard a story about a guy running a large scale reaction at low temps for several days and cooling with LN2, and just adding more each day to his dewar. After several days, the stirring shaft slipped from the motor, dropped through the bottom of the flask, dumping the organics into the dewar, now mostly filled with LOX. The ensuring blast took out most of the lab, fortunately the only person around was near the doorway and was through through it by the blast. This came from a guy who worked near that lab, so I believe it, but it was many years ago, so less caution then. But always a possibility with LN2.
View user's profile View All Posts By User
 Pages:  1  2

  Go To Top