Wright’s Well Control Services (WWCS) performed a hydrate remediation in the Gulf of Mexico at 7,200’ water depth from a proprietary skid containing a pump and motor. This self-contained subsea unit is powered from the surface through coiled tubing from a Multi-Service Vessel (MSV). Not limited by a Remotely Operated Vehicle’s (ROV) hydraulic energy, the subsea pump can increase volume up to 1 bpm, or reverse flow drawing pressure down to a sub-ambient -12 psi. For this project the integrated skid cleared 15 miles of 12” pipeline removing 9,000 barrels of hydrocarbons, condensate, gases and other fluids.
For a subsequent job, a paraffin and asphaltene blockage mixed with hydrates was successfully mitigated reopening four miles of pipeline. To date the skid has cleared a total of 30 miles of pipeline.
WWCS Gas Separator - Engineered to Prevent Hydrate Blockages within the Skid and its Coiled Tubing
A unique WWCS gas separator sits atop the skid and removes the gas mixed in the hydrate to the surface. This approach prevents the formation of additional hydrates in the coiled tubing outtakes used by both the gas separator and the pump for the remaining fluids. The old technique required returning the coiled tubing to the surface for thawing each time hydrates formed and reconnecting to the subsea pump–causing costly delays.
This system is further protected from hydrate blockages between the pipeline end termination/flowline end termination and the skid by injecting dispersant chemicals from a ROV panel as needed.
Engineered by WWCS to Ensure Safety
WWCS has engineered in a triple-redundant safety system to compensate for a loss of dynamic positioning (DP) or drive-off by the MSV from which the hydrate skid is deployed. An emergency quick disconnect (EQD) removes the skid’s coiled tubing connections via four hot stabs. Accumulators provide an isolated source of hydraulic power for the EQD which can be activated acoustically from the vessel, with ROV manipulators, or as a last resort with wire ropes. This safety system eliminates potential damage to the pipeline asset from the hydrate skid dragging across the seabed or thousands of feet of coiled tubing crashing down on the remediation site.
Engineered by WWCS to Protect the Environment
The skid has a number of environmentally friendly features. The pump is powered by filtered sea water avoiding any adverse impact from leaking or severing of the coiled tubing. The fluids the hydrate pump sends to the surface are contained in a specially designed tank on the deck of the MSV. Lastly, in the event of a MSV drive-off or loss of DP, emergency shut-off valves minimize the release of any hydrocarbons from the coiled tubing outtakes after an EQD. WWCS is currently developing a flush loop to eliminate any hydrocarbon release from an EQD deployment.
Shallow and Inland-Water Capabilities
The WWCS Hydrate Remediation System is also the solution of choice for shallow and inland-water pipelines. Depending on the