There is general industry recognition that production chemistry is a growing concern, from the conceptual design and FEED stage through the lifetime of operations. The global opportunities within the subsea market, both greenfield and brownfield, have only become more complex.
The increasing complexity in subsea fields has brought significant challenges in terms of scale control and management, highlighted by the uncertainties of scale risk evaluation. Because of the lack of reliable water compositions (e.g., commingled water), inhibition chemicals are more vulnerable to degradation in harsh subsea environments, and well access and interventions become difficult and costly.
The main challenges facing continuous scale inhibitor applications are associated with the limited chemical injection line, long tieback with large pressure and temperature variations, and long residence time, while well access and downhole placement can be particularly challenging for squeeze applications. The inadequate water data, the potential ion stripping, and the limitation of currently used thermodynamic scale prediction software all contribute to the uncertainty and inaccuracy in scale evaluation.
This paper will provide an overview of the scale management challenges associated with subsea fields while focusing on the development in laboratory evaluation techniques over the years, as well as on analytical advancement, hardware developments, and modeling integration practices.