Offshore Gas Safety Safety has Top Priority for Offshore Gas Industry
Safety has top priority in the offshore gas industry, but accidents still happen — occasionally with disastrous results. How does the industry work with reducing risks, and how successful has it been?
On July 6, 1988, a series of explosions ripped through the Piper Alpha oil and gas platform off the northeast coast of Scotland. Within two hours 167 men lost their lives, making Piper Alpha the world’s worst offshore disaster. Now 25 years later, there has been great progress on safety, but the volatile nature of hydrocarbons means there will always be risks in drilling for, transporting, and processing natural gas.
Ken Arnold, senior technical adviser for Worley Parsons, who has nearly 50 years in the oil and gas industry, including 16 at Shell, says the biggest offshore safety issue is loss of containment. “Hydrocarbons are safe if you keep them where they are supposed to be,” he says. “The danger comes when they start to leak out. So the greatest effort is to make sure we never lose containment. That possibility is always there, but the goal is to minimize those occurrences.”
Human Error Common Cause for Accidents in Offshore Operations
As with Piper Alpha, most offshore accidents are caused at least partly by human error. “It is documented that 80 to 90 % of all accidents are due to humans in action,” says Arnold. “But you could also say that 80 to 90 % of accidents are due to design mistakes. You need to do designs in such a way that if something goes wrong, the natural reaction of the human who has to interface with it is to do the right thing. And that is not always the case.”
To reduce the chance of accidents being caused by equipment failure, there is constant demand by oil and gas companies for more reliability from equipment suppliers. “The more reliable equipment is, the safer it is by definition,” says Arnold. “Things rarely go wrong when everything is operating as it should. It is in shutdowns, start-ups, construction and maintenance that we expose ourselves to greater risk.”
Gas Industry One of the Most Extreme Environments for Heat Exchangers
The gas industry is one of the most extreme environments for heat exchangers. In heat transfer applications at gas-sweetening plants — where hydrogen sulphide and carbon dioxide are removed from the gas — temperatures can reach 140 °C and pressures sometimes touch 35 bar. Add into the mix highly toxic gases, plus the fact that gas-sweetening systems are among the most challenging duties for polymer gaskets, and there is simply no room for error.