I've come across ther term "thermosyphon" in connection with reboilers on columns. I guess it implies flow of liquid induced by thermal gradient or something...
Can anyone give me a simple but correct explanation of "thermosyphon"?
John.
J.
Sometimes control rooms are the designated mustering point for plant personnel in case of emergency. (I don't know how common this practise is.)
Has the wisdom of this practise been examined and written about? Does anyone have examples of a control room providing refuge during a real emergency...
The second investiagation report into the Buncefield, UK, storage facility fire revealed that there was significant failure of bunding around tanks.
Three types of bund failure occurred:-
1. loss of sealant between concrete panels from fire and hydraulic forces
2. loss of sealant around bund...
Hi All.
As a non-metallurgist I have a question.
If steel that is not rated for low temperature service experiences a low temperature excursion it can become brittle and thereby weakened. Correct, so far?
What I'd like to know is if it subsequently returns to the higher temperatures of its...
Do plants ever have installed systems of fans or blowers to disperse an inadvertent release of inflammable gas? I've heard it mentioned that this might be done on some offshore rigs.
Could this approach minimise the chances of explosion following an accidental release? Could it increase the...
Hello All.
Is there a practise or has there ever been a practise of filling the tyres of earth moving trucks, or others, with water?
I've heard this was done on a large hydo scheme in Australia in the 50s.
Apparently someone invented a valve that allowed almost complete removal of air from...
An investigation report into a fire in a ship's funnel says taht firefighters applied 8 tonne of "liquid carbon dioxide." The term was used several times.
CO2 sublimates, doesn't it? Is there a liquid form? Is there some way CO2 can be bound to a liquid for firefighting purposes...
We've had a few discussions on HAZOP topics in the past.
Here's a simple question.
Do HAZOP teams consider the possibility of gross negligence from personnel? Say deliberatley de-activating a safety interlock, or removing some safety barrier, or even - heaven forbid - drunkeness?
Don't want...
Hi All.
Some OHS professionals and commentators discourage the use of the "A" word. They say it perpetuates the notion that "accidents happen", nothing we can do about it, in the lap of the gods, and so on.
Does anyone know of any research to determine exactly what sections...
There were some very good links given in thread 135-78 that very well describe the HAZOP process.
I have a question - anyone with actual experience on HAZOP teams might be able to help.
When the team considers a deviation at some point in the plant, they then identify the consequence. If the...
Hello to all who engaged in the discussions about accident investigation. I'll start this as a new thread (when they get long, they sometimes take me a long time to download. Bit of a change in direction too.)
I don't know about others, but I can get more genuine value out of these forums than...
Hi All,
Here's an example of a heat exchanger behaving oddly. The personnel present were unable to manage the problem, and only when the exchanger was stripped down and examined could the trouble be diagnosed. This probably doesn't give the answer to the problem that started an earlier thread...
<let's call this topic "accident/interview/statement - Part II">
I'd like to add this "contribution" to the discussion from The Melbourne Age (Australia), Jan 25 2003. It comes from an article by journalist Gary Tippet, covering a coronial inquest into a five-fatality road...
Here's a hypothetical.
Let's say you find yourself implicated in a serious incident (accident). You're the person who has made the "unsafe act" that may have directly lead to the accident. You may not be the only party involved, but you are the one that stands out. The consequences...
Hello All,
Some exciting stuff floating around in the world of safety. Have a look at:
http://www.visualforensics.com
Dr Ginsberg has taken the notion of putting together the stories told around accidents and representing them to juries in a computer graphic format.
What do people think of...
Here's a more serious example of miscommunication on a technical topic.
I heard an expert witness in a major trial asked to define "specific heat".
He answered that specific heat is the relative measure of a body to give off heat.
Now that's not correct, is it? Specific heat is a...
Hello All,
From the perspective of incident investigators, is there an accepted definition of an "explosion" of a vessel?
A vessel might rupture, rip apart, and violently release its contents. But if the vessel remains in one piece, is that an explosion?
If the vessel blows apart...
Intersting how a simple question like "What is the difference between psig and psia?" can trigger off much discussion.
I've never been comfortable with the term "back pressure".
To me, a pressure just exists and doesn't point forwards or backwards. Does anyone have a clear...
Can anyone tell me the chemical name or formula of "Thermex", please? There was a release of Theremex gas in the UK from a chemical plant, but no description of what it is or what it is used for. The report said it is an irritant and smell like geraniums.
John.
