Abstract: A free-standing riser system connects a subsea source to a surface structure. The system includes a concentric free-standing riser comprising inner and outer risers defining an annulus there between. A lower end of the riser is fluidly coupled to the subsea source through a lower riser assembly (LRA) and one or more subsea flexible conduits. An upper end of the riser is connected to a buoyancy assembly and the surface structure through an upper riser assembly (URA) and one or more upper flexible conduits, the riser also mechanically connected to a buoyancy assembly that applies upward tension to the riser. The riser may be insulated for flow assurance, either by a flow assurance fluid in the annulus, insulation of the outside of the outer riser, or both. The system may include a hydrate inhibition system and/or a subsea dispersant system. The surface structure may be dynamically positioned.

Abstract: A system for transferring fluids from a free-standing riser to a surface vessel comprises a first valve assembly including a first valve spool and a first isolation valve configured to control the flow of fluids through the first valve spool. In addition, the system comprises a second valve assembly releasably coupled to the first valve assembly with a hydraulically actuated connector. The second valve assembly includes a second valve spool and a second isolation valve configured to control the flow of fluids through the second valve spool. Further, the system comprises a deployment/retrieval rigging coupled to the first valve assembly and configured to suspend the first valve assembly and the second valve assembly from the surface vessel. Each isolation valve has an open position allowing fluid flow therethrough and a closed position restricting fluid flow therethrough, and each isolation valve is biased to the closed position.

Abstract: A free-standing riser system connects a subsea source to a surface structure. The system includes a concentric free-standing riser comprising inner and outer risers defining an annulus there between. A lower end of the riser is fluidly coupled to the subsea source through a lower riser assembly (LRA) and one or more subsea flexible conduits. An upper end of the riser is connected to a buoyancy assembly and the surface structure through an upper riser assembly (URA) and one or more upper flexible conduits, the riser also mechanically connected to a buoyancy assembly that applies upward tension to the riser. The riser may be insulated for flow assurance, either by a flow assurance fluid in the annulus, insulation of the outside of the outer riser, or both. The system may include a hydrate inhibition system and/or a subsea dispersant system. The surface structure may be dynamically positioned.

Abstract: A free-standing riser system connects a subsea source to a surface structure. The system includes a concentric free-standing riser comprising inner and outer risers defining an annulus there between. A lower end of the riser is fluidly coupled to the subsea source through a lower riser assembly (LRA) and one or more subsea flexible conduits. An upper end of the riser is connected to a buoyancy assembly and the surface structure through an upper riser assembly (URA) and one or more upper flexible conduits, the riser also mechanically connected to a buoyancy assembly that applies upward tension to the riser. The riser may be insulated for flow assurance, either by a flow assurance fluid in the annulus, insulation of the outside of the outer riser, or both. The system may include a hydrate inhibition system and/or a subsea dispersant system. The surface structure may be dynamically positioned.

Abstract: A system for transferring fluids from a free-standing riser to a surface vessel comprises a first valve assembly including a first valve spool and a first isolation valve configured to control the flow of fluids through the first valve spool. In addition, the system comprises a second valve assembly releasably coupled to the first valve assembly with a hydraulically actuated connector. The second valve assembly includes a second valve spool and a second isolation valve configured to control the flow of fluids through the second valve spool. Further, the system comprises a deployment/retrieval rigging coupled to the first valve assembly and configured to suspend the first valve assembly and the second valve assembly from the surface vessel. Each isolation valve has an open position allowing fluid flow therethrough and a closed position restricting fluid flow therethrough, and each isolation valve is biased to the closed position.

Abstract: A free-standing riser system connects a subsea source to a surface structure. The system includes a concentric free-standing riser comprising inner and outer risers defining an annulus there between. A lower end of the riser is fluidly coupled to the subsea source through a lower riser assembly (LRA) and one or more subsea flexible conduits. An upper end of the riser is connected to a buoyancy assembly and the surface structure through an upper riser assembly (URA) and one or more upper flexible conduits, the riser also mechanically connected to a buoyancy assembly that applies upward tension to the riser. The riser may be insulated for flow assurance, either by a flow assurance fluid in the annulus, insulation of the outside of the outer riser, or both. The system may include a hydrate inhibition system and/or a subsea dispersant system. The surface structure may be dynamically positioned.