Design of DEH Systems for Hydrate Management

Hydrate management by direct electrical heating (DEH) has proven to be reliable, easy to operate and cost effective. DEH requires limited modifications of the pipelines, i.e. electrical grounded connections at both pipe ends, a cable piggybacked to the pipeline and additional anodes at both pipe ends. Pipeline anodes may in most cases be combined with the anodes for cathodic protection. The system is applicable of conventional pipelines supplied with thermal coating. The first installation was in 2000 and more than 25 subsea pipelines are now supplied with DEH. There have been some failures, which have been caused due to inflicted damages. However, repairing has been successfully carried out achieving full functionality. Copyright © 2014 by the International Society of Offshore and Polar Engineers (ISOPE)