4 ms·

A few days ago some people on this forum were arguing that H2 is safe, just has an unfair reputation, and is a suitable replacement for gasoline. Well, is safe

A few days ago some people on this forum were arguing that H2 is safe, just has an unfair reputation, and is a suitable replacement for gasoline. Well, is safety's not a concern, then for many applications H2 is a suitable or superior alternative to He that is abundant and renewable. More lift More heat transport Faster c Only 10K higher Tb Unless you're dealing with unsaturated carbohydrates easy win! Heck, at work we are trying to retrofit our He system to run on H2 to get a massive performance boost (my idea) and ditch the He recycling system. You wouldn't believe the pushback I got! Eventually we realized we couldn't hit the performance metrics without H2, but these folks were all upset about H2 heated to 800K. Cowards.

jojobas 3y ago
Where is safety not a concern? Apart from the obvious risk of blowing up, every structural material has to be reviewed for hydrogen embrittlement. Call me a coward but I would not work near a substantial quantity of 800K hydrogen either.
- thsksbd 3y ago
  I was taking a jab at people who, a few days ago, were arguing that H2 is just as safe or safer than gasoline. I'm scared of gasoline, and petrified of H2. But our project needs H2
mianos 3y ago
For many but not MRIs as the super conducting material most commonly used, niobium-titanium, is not a super conductor at the boiling point of hydrogen.
- anonuser123456 3y ago
  Meh. Soon enough we'll have REBCO based MRIs.
  - maccam94 3y ago
    I looked around last week to see if they are on the market yet, and found that Philips already seems to have helium-free MRIs for sale. I'm not sure if they just sealed it better or switched to REBCO. edit: nvm, finally found more info. it's just better sealed helium https://www.usa.philips.com/healthcare/resources/landing/the-next-mr-wave/sealed-mr-technology https://www.usa.philips.com/healthcare/resources/landing/the...
    - anonuser123456 3y ago
      My understanding is that most of the experiments for NMR with REBCO at this point are geared towards high field NMR (like 30T) whereas medical NMR field strength is down around 1-3T. I don’t know what the cost delta is between LTS and HTS magnets, but I imagine the much broader applicability of HTS will bring manufacturing costs way down with economies of scale. In the interim, people are still trying to figure out effective ways to joint the HTS sections.
- thsksbd 3y ago
  I was being cheeky (at those who were recently minimizing the risks H2)

jojobas 3y ago

Where is safety not a concern? Apart from the obvious risk of blowing up, every structural material has to be reviewed for hydrogen embrittlement. Call me a coward but I would not work near a substantial quantity of 800K hydrogen either.

thsksbd 3y ago
I was taking a jab at people who, a few days ago, were arguing that H2 is just as safe or safer than gasoline. I'm scared of gasoline, and petrified of H2. But our project needs H2

mianos 3y ago

For many but not MRIs as the super conducting material most commonly used, niobium-titanium, is not a super conductor at the boiling point of hydrogen.

anonuser123456 3y ago
Meh. Soon enough we'll have REBCO based MRIs.
- maccam94 3y ago
  I looked around last week to see if they are on the market yet, and found that Philips already seems to have helium-free MRIs for sale. I'm not sure if they just sealed it better or switched to REBCO. edit: nvm, finally found more info. it's just better sealed helium https://www.usa.philips.com/healthcare/resources/landing/the-next-mr-wave/sealed-mr-technology https://www.usa.philips.com/healthcare/resources/landing/the...
  - anonuser123456 3y ago
    My understanding is that most of the experiments for NMR with REBCO at this point are geared towards high field NMR (like 30T) whereas medical NMR field strength is down around 1-3T. I don’t know what the cost delta is between LTS and HTS magnets, but I imagine the much broader applicability of HTS will bring manufacturing costs way down with economies of scale. In the interim, people are still trying to figure out effective ways to joint the HTS sections.
thsksbd 3y ago
I was being cheeky (at those who were recently minimizing the risks H2)