Presenters: Leila Eyni, NTNU, Heiner Schümann, SINTEF and Fredrik Lund, EMPIG
These conditions of high pressure and low temperature are likely to cause the formation of hydrate and wax particles that can lead to increased pressure drop and gradual or sudden plugging. Traditional measures to address hydrate and wax formation often involve the injection of chemicals, costly thermal insulation, or heating that have a high environmental footprint. An alternative measure less costly and more environmentally friendly is cold flow. Cold flow consists of inducing in a controlled manner the formation of hydrate and wax particles and the subsequent formation of a stable liquid slurry that does not agglomerate and plug the pipe downstream. This process is performed in a unit that consists of a reactor and cooler.
This study presents a technical and environmental evaluation of a cold flow technique to produce an oil reservoir using a long tie-back and comparison against traditional development concepts. The case study is a synthetic field located on the Norwegian Continental Shelf. Several development alternatives were considered and compared: 1. production to an FPSO, 2. tie-back production over a distance of 100 km to an existing offshore platform using pipeline heating and 3. tie-back production over a distance of 100 km to an existing offshore platform using cold flow. Two reservoir recovery methods were considered: gas injection and water injection. A commercial transient multiphase simulator was employed to model the subsea system for the tie-back solutions. An analytical model was developed to compute the carbon emissions for each concept and the footprint of required infrastructure.