Sand production and erosion can have significant financial and safety consequences for both production and assets, estimated by experts to run into tens of billions of dollars annually. Now DNV GL has developed industry guidance to enable operators to develop a strategy for optimising the production rate, while at the same time safely managing the sand production and thereby potential erosion damage.
The recommended practice (DNV GL RP-0501) describes a safe and cost-effective approach to sand management and handling the consequences of sand production from oil and gas reservoirs through production wells, flowlines and processing facilities.
Lars Even Torbergsen, senior principal specialist in DNV GL – oil and gas says: "Sand production is a major issue for the industry.
"Typical failures include erosion, sand accumulation, plugging and contamination. This can lead to unplanned shut-downs and loss of product to the environment. DNV GL’s recommended practice (RP) provides guidance on how to safely and effectively manage this challenge through the different stages of the design and operation of oil and gas production facilities.
"Statoil’s Gullfaks development applied the sand management RP’s principles a few years ago. Due to potential sand production, about 50% of the Gullfaks wells had to be choked back. The new sand management strategy reduced this by about 50%, adding a significant amount to the revenue stream. With an oil price of about $50/b, this is equivalent to around £175m per year. The knowledge we obtained from this work is encapsulated in the updated RP."
First issued in 1996, the updated RP now includes new guidance on the development, implementation and follow-up of a high-level sand management strategy. It also provides more background material for erosion response models.
The RP includes the following main updates:
- An outline and list of considerations for a sand management strategy
- New guidance on the erosion model for flexible pipes with interlock carcass
- New erosion models for choke valves
- Erosion model validation cases
- Guidance on computational fluid dynamics (CFD) erosion modelling
The RP was initially developed as a result of a joint industry project (JIP) involving DNV GL, Amoco Norway Oil Company, Conoco Norway Inc., Norsk Hydro AS, Saga Petroleum AS and Statoil. The 2015 update reflects the collaboration between DNV GL and Statoil on the development of sand management strategies for the operator’s North Sea activities.
Elisabeth Tørstad, CEO, DNV GL – Oil & Gas, says: "DNV GL runs joint industry projects (JIPs) in collaboration with its customers to develop new solutions, standards and recommended practices that strip back complexity and can help manage costs without compromising on safety. We continuously lead approximately 100 joint industry initiatives, providing the sector with an independent arena for collaboration and innovation."