The Concerns and Benefits of Standardization on the Heidrun Subsea Water Injection System

Abstract Ms paper describes the process of standarzing the Heidrun Sub sea water injection system. The layout, basis of design and equipment utilized are presented, along with exploring the benefits and concerns of adopting a standard sub sea system. Realized by this approach were: the interchangeability of equipment between Heidrun and other licenses, the lowering of development costs, the capturing of key-lemmings and the sharing of resources. By identifying and weighing the benefits versus the concerns, standardization can be successfully utilized between petroleum companies with different project parameters, thus saving significant costs for all parties. Introduction There are marry benefits, concerns, and reward associated with standardizing a sub sea system. In the earlier stages of the Heidrun development, several sub sea concepts were evacuated, ranging from individual water injection wells tied back to the Tension Leg Platform (TLP), to multiple-well sub sea templates. It was recognized that substantial savings and synergies could be achieved if the Heidrun Project chose art economically viable development concept which fit into Statoil's long-term strategy for sub sea developments (being that Statoil would take over operator ship of the Heidrun field at first-oil). After evaluation, it was decided that the Heidrun Sub sea Water injections System would be modeled after Statoil's Stratford Satellite Project (SSP) design. However, there were problems. Operating parameters specific to Heidrun, would have to be met. Agreements had to be reached on the use of the existing specialized sub sea tools which were not part of the Heidrun partnership. Finally, capturing the knowledge already hard-won by SSP had to be integrated into Heidrun. This paper describes the Heidrun sub sea water injections system specifics, and shows the process of working through concerns and thereby realizing the benefits of standardization. Heidrun Subsea Water injection System Description The Heidrun Field is roughly 10 km long and 6 km wide (figure 1). It is situated on the mid-Norwegian Continental Shelf in an area known as Haltenbanken, 175 km from the Norwegian coast in Production Licenses 095 and 124. The field lies pre-dormis within Block 6507/7 with an eastern extension into Block 6507/8, and in water depths ranging from 310 to 348 meters. The major reservoirs consist of the Fangst Group, the Upper and Lower Elfie, and the Are Formations, all of Jurassic age. During the planning stages, it was recognized that perimeter sub sea water injection wells would be required to reach the water column in some of the existing fault blocks. The option of extended reach wells from the TLP was explored, but was rejected due to technical difficulties and associated costs. Six water injection we] Is were deemed necessary for optimum, initial water injection and were planned to be drilled from two seabed locations.