Where a leak repair, going forward, is not successful a means of capturing the fugitive emissions is required. A methodology has been trialled around a leaking SF6 gas insulated switchgear flange to prove its effectiveness during the latter part of 2012. This method utilised diverting the fugitive emission through an adsorbent material (activated carbon) which once saturated would allow the gas to reclaimed by further processing. Although this trial was successful its future sustainability is questionable therefore design changes have been made which enable the gas to be collected and pumped into a storage vessel.
Both designs are based around, ideally, not needing an outage to install it, but if an outage is required because the leak infringes safety distances, it should be able to be installed within 2 days to enable installation within a weekend outage. The bottle reclamation principle is being carried forward and a prototype system is currently being designed.
In addition work is being conducted with the University of Liverpool to analyse the carbon captured SF6 to assess its suitability for re-use after reprocessing.