ExxonMobil to use repaired gas compressor as model for replacement

Last Updated on Thursday, 4 March 2021, 20:32 by Denis Chabrol

ExxonMobil on Thursday said the repaired flash gas compressor is due back shortly from Germany and would bring an end to weeks of flaring of large quantities of natural gas and at the same time that equipment would be used as a model for a new and upgraded version.

“We will utilise these upgrades that we’ve made, install  the machine, run it,  monitor it closely, validate the update we have made for making further improvements that we are able to do with the new machine that we are not able to do on this one,” Production Manager of ExxonMobil Guyana, Mike Ryan told a virtual briefing.

He said the new compressor, which was ordered last year to be a spare, would now be used as a replacement when it arrived by year-end even if the repaired one works well. “The current plan right now is that it is not a spare; it is a new machine that will be replaced with the current one that’s going in,” he said.

The flash gas compressor was taken out of the Floating Production, Storage and Offloading (FPSO), Liza Destiny, and flown to the German manufacturer, MANN Solutions, several weeks ago after the rubber seal broke. The company hopes that the compressor would return to Guyana and be reinstalled by the end of March.

Mr. Ryan said his company has used that this recent inspection and upgrade to make a number of modifications to the existing compressor. He was confident that “it will operate better than it did in the past.”

The ExxonMobil official said the flash gas compressor was damaged because the shaft was vibrating abnormally along its length. Mr. Routledge suggested that the vibration problem might not have been altogether resolved. “What we are trying to work through is how do you eliminate that, both short-term and long-term for a lasting solution,” he said.

He dismissed suggestions in sections of the media that all ExxonMobil needed to do was to reduce production by 15,000 barrels per day to reduce the amount of natural gas that was being flared into the atmosphere.  “We cannot compress that low-pressure stream without the flash gas compressor no matter what the production level is  and so comments like that are not correct but in order for us to get back to pilot flare we need that flash gas compressor or we need to reduce production to zero,” Mr. Ryan added.

Concerning the amount of gas flaring that is allowable,  the President of ExxonMobil Alistair Routledge said mention of 14 billion cubic feet in the Environmental Impact Assessment (EIA) during the first 18 months of operation did not amount to a limit and was not enforceable. “We, for one, are not above that number and that number is not a permit commitment nor was it an allowance,” he said.

With ExxonMobil now about to flare 13 billion cubic feet of  natural gas since start-up in December, 2018, he said that would not harm the environment.

Mr. Routledge said that figure was generated by a third party consultant as a basis for the various consultations, even as he maintained that ExxonMobil’s target was to get back to pilot flare at less than one million cubic feet per day.

Mr. Routledge emphasised that the current level of flaring at 14 million cubic feet per day was within the EIA benchmarks. “The conclusions of the Environmental Impact Assessment remain valid today that this is not causing any significant damage to the environment,” he said.