Page 148 - Pipeline Pigging Technology

The Zeepipe challenge

THE ZEEPIPE CHALLENGE:

PIGGING 810km OF SUBSEA GAS

PIPELINE IN THE NORTH SEA

INTRODUCTION

The Zeepipe Transportation System is being developed to deliver sales gas
from the Sleipner field and later from the Troll field in the northern part of the
North Sea to continental Europe. Delivery points will be Zeebrugge in
Belgium and Emden in Germany. The deliveries to Emden will be through the
Statpipe/Norpipe system (see Fig. 1). Fully-developed, Zeepipe will comprise
about 1300km of pipelines and will, togetherwith Statpipe/Norpipe, form the
backbone of Norwegian gas transport to the Continent. The gas transport
capacity of these systems will be significant; in terms of energy equivalent, it
will be three to four times Norway's present electric power consumption.
Phase 1 of Zeepipe will be operational by 1st October, 1993, and consists
of a 40-km, 30-in pipeline connecting Sleipner to the Statpipe system, and a
810-km, 40-in pipeline between Sleipner and Zeebrugge. An onshore receiv-
ing terminal for control and metering purposes will be located in Zeebrugge.
The Phase 1 daily transport capacity will be 39MMSCM (million standard
cubic meters). Relevant parts of the project schedule are shown in Fig.2.
Phase 2 will be operational 3 to 8 years later, and will connect the Troll field
to the Sleipner platform and to the Statpipe/Norpipe system, respectively.
Phase 3 is defined as installation of additional compressor facilities in the
system, including a possible future compressor platform approximately
midway between Sleipner and Zeebrugge. The timing of this phase is
dependent on further gas sales. The ultimate daily transport capacity will be
62MMSCM.
The 40-in diameter, 810-km pipeline from Sleipner to Zeebrugge will be
the longest and largest subsea pipeline ever built. The pipeline was originally
designed with a platform at the mid-point for tie-in of a future compressor
platform and to enable the line to be pigged in two sections. Recent advances

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