The production of both fines and matrix sand into the well bore is a common problem in water injection wells due to transient pressure and flow events. Conventional sand control techniques do not manage these transient events effectively, and the reliability of the sand control can be compromised as a result. In injection wells, a shutdown event results in a sudden stoppage of flow causing a surge which can result in powerful downhole pressure transient effects such as back-flow, cross-flow, and water-hammer. These effects can mobilize sand particles in the near-wellbore resulting in an influx of fine particles, screen plugging and erosion. Eventually, the accumulation of debris in the well can lower or block injection rates to the point where a water injector well must be repaired or replaced to maintain the injection volumes required for pressure maintenance and sweep in the reservoir. A new, sand screen compatible completion was designed with an array of integral non-return valves (NRV) to address these challenges. This paper will present an overview of the product development with computation fluid dynamics (CFD) modeling, flow-loop and laboratory testing. Design considerations of any potential adverse effects of the new non-return valves, such as plugging and erosion, were studied extensively in lab tests on a series of valve designs. Non-return valve completions could have the benefit of increasing injection volumes and extending the life-cycle of water injections wells.

In many open-hole completions in unconsolidated reservoirs, the preferred method of sand control is a conventional gravel pack across sand exclusion completion screens. To date the gravel pack options available for horizontal or highly deviated wellbores have been the use of brine-based gravel pack carrier fluids or the use of viscous gel packs using alternative path screen technology. The first option, using brine as the carrier fluid, has limited applicability because many reservoir intervals have brine-sensitive shale that, if not stabilized, can disrupt the gravel deposition during the alpha-beta (α-β) packing process, especially in long intervals. The second option, using alternative-path screens and viscous carrier fluids, overcome the shale destabilization issues but not without a compromise in the quality of the pack or the higher price tag.A third option is now available that utilizes a new, solids-free, invert emulsion gravel pack carrier fluid. This option overcomes the issue of shale destabilization and interupted gravel deposition often associated with brine packs because it avoids the exposure of water-sensitive shale to aqueous fluids.This paper provides the design details of a carrier fluid that overcomes the technical hurdles of a conventional brine-pack operation as well as the fiscal limitations associated with alternative path technology. Included are the planning and execution details of a 5-well, back-to-back gravel-packing operation from an offshore platform in the Bualuang Field, Gulf of Thailand whereby successful gravel deposition occurred on each well using a invert emulsion system as a carrier fluid. The results presented of this case history sequence clearly demonstrate a world class break-through and triumph for the oil industry.

In 2014, an R&D project was intitiated to develop an innovative technological solution to improve the performance and reliability of Deepwater Gulf of Mexico assets. The objective was to increase the life expectancy of Miocene and Lower Tertiary water injection (WI) wells, several of which had suffered a severe loss of injectivity within only a few years of completion. Before scoping out the project, an internal study was conducted to compile and analyse the available data. The root problem was identified as an accumulation of formation solids inside the lower completion; principally fine matrix sand that had been pulled in from the reservoir. These formation solids are normally stationary during steady injection, but can be mobilized during shut-ins (maintenance, pump problems, environmental conditions, etc.) due to powerful transient flow effects such as back-flow, cross-flow and even water-hammer. Eventually, enough solid fill can accumulate inside the lower completion as to diminish the injection rates. At this point the operator must consider some very expensive options such as to sidetrack or re-drill a new injector well. The obvious solution to this problem was to find a way to prevent the fine material from getting inside the completion. The challenge was to do so while sustaining high injection rates, with no loss of injection pressure or requirement for additional horsepower. Therefore, the goal of the project was to find a practical, efficient method of stopping the formation material from entering the lower completion during a shut-in cycle. To achieve this, a new flow control device (FCD) and completion system was developed with intrinsic non-return valves (NRV) that are designed to prevent any back-flow or cross-flow during the shut-ins. Also, depending on well conditions, the system will minimize the damaging effects of water-hammer: rapid, high-amplitude pressure cycles that can occur during a sudden stoppage of flow.