A coming-of-age tale (thankfully not mine) that nearly ended in disaster. For a couple of years in my late teens, I had a summer job at an industrial gasification plant just down the road from our farm.
East Fife in Scotland, where we lived, is coal country — West Virginia without the mountains and banjos. While most of the underground seams were by then depleted, surface-level outcrops were still being mined. The gasification plant was built to turn coal from one of these opencast sites into natural gas.
During the summer months, high school graduates, who supposedly had studied chemistry, were hired to fill in for workers on holiday. I snagged one of these jobs, though I couldn’t tell carbon dioxide (the fizz in your pop) from carbon monoxide (the deadly, colourless version your car emits).
Getting to the point, I was joined by a young guy called Freddy (think Fredo, from The Godfather, and you can see where this leads). He knew even less chemistry than I did (and I had failed that class in high school six years running), but his father was plant manager. This led to a hair-raising event (actually, hair-whitening) that should have been fatal.
But first, a little scene-setting. At one end of the plant, a quarter-mile-long conveyor belt carried coal to the top of an immense boiler, where it was tipped in through airlocks and gasified under tremendous pressure. At its lower end, the belt was staffed on either side by women whose job it was to chuck out lumps of stone and other non-combustibles.
One day, while they were busily engaged, a member of their crew passed by them — sprawled on the conveyor belt, unconscious. Did I mention this was a gas plant? Yes, and it leaked.
The mind boggles at what might have happened. Picture a pair of legs sticking out from the top of the boiler.
Not that this sort of thing was entirely unprecedented. For years workers had noticed birds flying high over the plant suddenly plummeting to Earth. Dead.
Back to Freddy. And I swear what follows is true.
Natural gas hadn’t enough calories to meet the plant’s specs, so they added liquified petroleum gas. This was stored in a huge cylinder about the size of a submarine. And it was located, ironically as things turned out, close to the safety hut.
Anyway, it was Freddy’s turn to draw a sample of the LPG to be tested for its calorific value — the owners wanted to know they weren’t being sold an inferior product.
You did this by attaching a container, rather like a thermos flask, to valves on the LPG cylinder, and extracting a small amount.
But since the cylinder itself was under immense pressure to keep the gas liquid, you had to follow a two-step process.
First, you cracked open the outer valve and screwed on the Thermos flask. Then you cracked open the inner valve and drew your sample.
The reason for this procedure became apparent when Freddy reversed it. He first opened the inner valve, then tried to crack open the outer one.
But LPG, when rapidly depressurized, immediately freezes onto any surface it contacts. In this instance, the surface in question was the outer valve.
It froze wide open, and a massive jet of LPG, instantly vapourizing, blasted out in a horizontal stream a hundred metres long and maybe 20 metres wide.
The vapour first enveloped the safety shed, covering the windows and walls in LPG ice. It then headed downwind, thankfully away from anything with a flame in it (i.e., most of the plant).
It took two guys with an enormous wrench to close that outer valve, by which time the surrounding area was white like hoarfrost with LPG residue (though not as white as those guys’ faces).
I have no idea the monetary value of the gas that escaped, but you guessed it, Freddy’s dad saved his job.
A higher power, however, saved his life, and then only because the men in the safety hut couldn’t open the door to get at him. It, too, was frozen in place.