Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

Hydrogen fire at Golden Empire Transit demolishes bus, tanks explode .... 7

Replies continue below

Recommended for you

It began as being used for gas street lights.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
 
There has been a lot of experience with hydrogen by Nasa, and in large power plants where the electric generator is larger than 250 MWe. There have been fires and explosions related to hydrogen leaks, but following basic guidelines has led to a managable use of hydrogen in those industries that have a trained workforce.

Straightforward guidelines can be found in Nasa's Safety Standard for Hydrogen and Hydrogen systems NSS 1740.16 < However, ignoring the special safety requirements , or use by untrained consumers, can lead to fires and explosions. Major fires and explosions had occurred at some Nasa rocket sites, and also had occurred at some large electric utilities , when the guidelines were not followed.

H2 will leak out of flanges, threaded fittings ,valve seats , and faulty welds. Upon leakage to the atmosphere it will ignite nearly spontaneaously , as it has a very low energy of ignition requirement; a simple particle of rust impinging on a pipe is enough to spark a fire or explosion. The H2 fire is nearly invisible, and early efforts to determine the location of a H2 fire ( by "rocket scientists" ) included waving a straw broom ahead of the operator as he walks around , or throwing a handful of sawdust in the air ahead of the operator.

Nasa recommends the H2 transport pipe be the highest pipe in the pipe rack, and never to route H2 pipes underground, as a leak ( caused by corrosion) will cause H2 to leak into unpressurized drainage pipes in the vicinity , and just flushing a toilet can lead to a sewer explosion.



"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick
 
davefitz reminds us of the seminal NASA Hydrogen Safety guidelines:

Nasa recommends the H2 transport pipe be the highest pipe in the pipe rack, and never to route H2 pipes underground,

But Germany, Denmark and other European countries have plans for high-pressure underground hydrogen pipelines ..


Since hydrogen piping systems become MORE DANGEROUS when routed underground, how can this be reconciled ?

Anyone ???

MJCronin
Sr. Process Engineer
 
There is a process:

Propose an impossible project.
Secure the funding.
Exhaust the funding on studies and red tape.
Determine the project technically infeasible.

It's a form of money laundering.
 
waross (Electrical) said:
The earth is NOT CO2 neutral.

True my mistake. Your right there is no carbon foot print, since earth is carbon neutral.
And most all Co2 is used up by vegetation, so no worries there.
Except for the wild fires? See my post in the Hawaiian fires.
 
"And most all Co2 is used up by vegetation, so no worries there."

It is held until it dies and rots - some becoming an even more potent methane, roughly 40X more problematic. This is typically a 50 year cycle.

The current carbon fuel supply represents millions of years of plant growth and burial. Unless one is foreseeing millions of times the current number of trees one cannot count on vegetation to deal with the reintroduction into the environment.
 
3DDave (Aerospace) said:
"And most all Co2 is used up by vegetation, so no worries there."

It is held until it dies and rots - some becoming an even more potent methane, roughly 40X more problematic. This is typically a 50 year cycle.

The current carbon fuel supply represents millions of years of plant growth and burial. Unless one is foreseeing millions of times the current number of trees one cannot count on vegetation to deal with the reintroduction into the environment.

Again the earth is a closed system. All that is nothing to worry about. Its made to fix itself. "Nothing new under the sun".
 
Hey folks, late to the game, am only now reading this news story. Question: is this a hydrogen fire? — besides the headline the footage is of a $1.1 million, fuel cell bus on fire. These are lithium electric buses, with a composite hydrogen tank, but maybe the fire was caused by the lithium batteries, or any of a hundred things like wiring faults, or fluid leaks, or brakes, etc. I am dubious that this is a hydrogen fire, and am interpreting the headline to read as *Hydrogen (Bus) Fire*.

Edit: Apparently CA is a trial ground for new technologies; already they are running hydrogen tanker trucks up and down Interstate 80, and New Flyer bus states the hydrogen bus is potentially autonomous, compounding the curiosity of it all.
 
Status
Not open for further replies.
Back
Top