How much disruption to petrol supplies will there be with Grangemouth shutting down ?

Question

What's involved in turning a refinery off ? How does it affect North Sea Oil Production ? Do they have to turn off the oil rigs ? More importantly how do you turn it back on again ?

Answer 1

none if people dont panic buy!! There always 3 months reserves so no problem

Answer 2

For your info - the forties pipeline, which carries crude oil from about 55 north sea rigs, comes in just upstream of Grangemouth refinery at Kinneil processing plant. At kinneil, the gasses are taken off (ie the crude oil is stabilised) and the crude is either sent to the refinery, or out to tankers at Hound Point on the river Forth, for export.

The only reason that Grangemouth refinery shutting down causes the north sea rigs to shut down, is because we at Kinneil, (about 1/2 mile up the road) receive our steam from the refinery power station. We need steam to process the crude before it goes to the refinery.

So it is our lack of steam at Kinneil processing plant which necessitates the shutdown of our pipeline from the north sea.

The strike at Grangemouth DOES NOT directly affect the north sea whatsoever. It's only the fact that they supply us with steam. if we had steam here, there would be no rigs shutting down, and the forties pipeline would be kept open. The oil which we normally send to the refinery next door, would just be exported via tankers instead.

BTW - shutting a refinery down is a long process to shut down safely. In emergencies, the plants can trip and vent to flare, but it is an unstable condition, and to be avoided wherever possible - controlled shutdown is safe. The ethylene crackers, and poly plants were first to shut down. the throughput of crude to the refinery Crude Oil Distillation units is reduced, this reduces product. Eventually the last thing left running will be the refinery power station, which provides power and steam utilities to the site. Emergency power will then be taken from the national grid for the duration of the strike. This shut down operation takes about a week or so.

The north sea rigs affected will be shut down in a controlled manner also. Firstly using 'selected well' shutdowns to reduce throughput, then eventually shutting all hydraulic sub surface safety valves to to completely stop the wellflows. Starting back up a rig is a longer process - most wells will not actually produce just by opening the wellhead and chokes up - they need artificial lift to reduce the density of the oil, as the reservoir pressures have decayed over time. This will be usually accomplised using Nitrogen in older platforms. Eventually the crude will flow, the gas will be removed, and instead of the nitrogen, the gas will be reinjected. Newer platforms/wells, will sometimes flow immediately, depending on the pressure in the oil reservoir beneath.

hope that helps.

Answer 3

They said that if it shuts down this weekend that it will be a month before it starts to produce again .Hope that they can move supplies up north if it happens or there will be a lot of people going no where fast ,we won't be able to get to work