Anagen™ Freeze

Overview

Until Anagen™ Freeze, taking fluid-filled cables (FFCs) out of service at the end of their useful life, involved either completely removing the cable or trying to remove all the oil before leaving it in-situ.

Removing the cable requires it to be exposed along its entire length (generally through trenching), followed by sectioning and disposal. This approach is expensive, time-consuming, and may result in environmental damage. The presence of additional infrastructure (both above and below ground) can create significant complications and it is often necessary to consider the topography of the cable route. In urban areas, there may also be significant disruption to local communities.

Removing the oil is comparatively simple and inexpensive and can be carried-out with a minimum of disruption by isolating and then purging the cable. However, gas purging does not remove all the oil and a significant proportion (up to 50%, depending upon cable design) is retained within the insulation paper. Over time, this fluid can drain from the paper and flow towards the lowest point in the cable. Should it encounter a cable defect the cable will leak.

Anagen™ Freeze, is a fluid that mixes with the residual oil, retained within the insulation papers after purging, and immobilizes it, removing the risk of future leaks and enabling the safe in-situ decommissioning of fluid-filled cables.