As offshore exploration and production projects move into deeper waters, the flow assurance issues that operators face have grown larger in scale and more complex, an expert said.
In a presentation held by the SPE Flow Assurance Technical Section, “An Insight to Current Flow Assurance Technologies,” Phaneendra Kondapi discussed the technologies being used and developed to solve the problems related to flow assurance in offshore projects. Kondapi, chairman of the technical section, is a senior technical adviser at Granherne, a subsidiary of KBR, and a professor of subsea engineering at the University of Houston.
The problems commonly found in flow assurance are listed in the following categories:
- Production chemistry: The formation of deposits such as hydrates, waxes, paraffins, scales, and asphaltenes that clog pipelines
- Operations: Slugging, foaming, emulsions, and sand production
- Integrity: Corrosion and erosion
Kondapi named five areas of technological developments that address and remedy the problems. The solutions are thermal, chemical, hardware, operating, and software.
Thermal solutions are used to prevent the buildup of hydrates and waxes, Kondapi said. Some of the solutions are mature technologies, meaning they have been commercially available for at least 10 years. He said these mature technologies, such as thermal insulation, may need updating to be useful for offshore projects.
“Some of these technologies need to be improved … in order to meet the challenges of deepwater applications and high-pressure/high-temperature applications, and a few of them are getting old and may have to be replaced based on their restrictions and environmental concerns,” he said.
Other thermal solutions, such as electrically heated pipe-in-pipe systems, cold flow systems, and phase-changing materials, are in the embryonic stage of development; they are being run mostly in laboratory experiments. Kondapi said that while the development of direct electric heating has matured for hydrate and wax prevention, companies are developing methods to use the technology for plug removal.
Chemical solutions are applicable to a greater variety of flow assurance issues. Kondapi said that most of the chemicals, such as defoamers, asphaltene inhibitors, paraffin inhibitors, and chemical demulsifiers, are widely used in the industry. Uncommon chemical applications include the uses of methanol for hydrate prevention and plug removal, and ethanol for hydrate prevention.
Gas/liquid subsea separation is an emerging hardware application that helps increase oil recovery and prevent hydrate buildup and slugging. Separators have become the most targeted new technology for development by operators. In addition, further use of separators on deepwater projects could lead to significant cost savings, he said.
“Offshore industries are going deeper and deeper, and they’re going further off into the sea, so these depths and longer offsets are making flow assurance issues challenging, and operability also becomes very challenging,” he said.
Other emerging hardware solutions, such as subsea coolers, desanders, and coiled tubing tractors, are in the early development stage.
Kondapi gave examples of emerging technology in operating and software solutions: gas sweeping, real-time flow assurance advisory software, and real-time remote performance monitoring software.
He said that as the industry moves to offshore field development without production platforms, the development of new flow assurance technology must extend to subsea processing. Companies should look for ways to improve subsea separation, subsea power, boosting, and completions, he said.
The webinar is available at https://webevents.spe.org/products/an-insight-to-current-flow-assurance-technologies