The author describes the operator’s development of a culture of circular decommissioning, with the main goal of establishing a structured process to improve environmental performance by implementing principles of circular economy during the engineering and execution of decommissioning projects.
Culture of Circular Decommissioning
Within the operator’s energy-transition strategy, the culture of circularity has been developed to maximize mature-asset life and ensure that decommissioning projects adhere to an environmentally friendly circular process. The process is composed of the following four main systematic steps:
- Reuse or repurposing of an asset (for example, for carbon capture, use, and storage or for hydrogen, offshore-wind, photovoltaic, or geothermal purposes)
- Reuse of a portion of an asset (for example, reuse or reconversion of part of a platform or onshore installation)
- Reuse of components (for example, pumps, valves, heat exchangers, and compressors)
- Recycling of materials (for example, steel, copper, aluminum, or rare elements)
Circular Approach for Engineering New Assets
Embedding circularity into the engineering of new assets is critical because proper setting of component design can increase the probability of future reuse and repurpose with only minor technical changes or specifications. Application of this circularity during the early stage of asset design is based on the transformation from a linear economy (take/make/dispose) to the circular economy (make/use/reuse/recycle).
The following aspects must be taken into consideration in order to embed the circular approach during the engineering of new assets:
- Reuse of preused assets for new projects
- Design for long-life assets, products, and components
- Modularization
- Design to reuse
Based on the operator’s previous experience, besides jackets and decks, the main types of preowned assets are represented by living quarters and process modules; offshore complex fields could offer considerable availability (Fig. 1 above). Another important concept is the reuse of huge structures such as jackup rigs or semisubmersibles and verifying their suitability for potential repurpose.
